Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Bio Zoology Guide Pdf Chapter 5 Digestion and Absorption Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

11th Bio Zoology Guide Digestion and Absorption Text Book Back Questions and Answers

Part I

I. Choose The Best Options

Question 1.
Choose the incorrect sentence from the following:
a. Bile juice emulsifies the fat
b. Chyme is a digestive acidic food in stomach
c. Pancreatic juice converts lipid into fatty acid and glycerol
d. Enterokinase stimulates the secretion of pancreatic juice
Answer:
d. Enterokinase stimulates the secretion of pancreatic juice

Question 2.
What is chyme?
a. The process of conversion of fat into small droplets.
b. The process of conversion of micelles substances of glycerol into fatty droplet.
c. The process of preparation of incompletely digested acidic food through gastric juice.
d. The process of preparation of completely digested liquid food in midgut.
Answer:
d. The process of preparation of completely digested liquid food in midgut.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 3.
Which of the following hormones stimulate the production of pancreatic juice and bicarbonate?
a. Angiotensin and epinephrine
b. Gastrin ¿md insulin
c. Cholecystokinin and secretin
d. Insulin and glucagon
Answer:
c. Cholecystokinin and secretin

Question 4.
The sphincter of Oddi guards
a. Hepatopanci’eatic duct
b. Common bile duct
c. Pancreatic duct
d. Cystic duct
Answer:
a. Hepatopanci’eatic duct

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 5.
In small intestine, active absorption occurs in case of
a. Glucose
b. Amino acids
c. Na+
d. All the above
Answer:
d. All the above

Question 6.
Which one is incorrectly matched?
a. Pepsin – stomach
b. Renin – liver
c. Trypsin – intestine
d. Ptyalin – mouth
Answer:
b. Renin – liver

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 7.
Absorption of glycerol, fatty acid and monoglycerides takes place by
a. Lymph vessels within villi
b. Walls of stomach
c. Colon
d. Capillaries within villi
Answer:
a. Lymph vessels within villi

Question 8.
First step in digestion of fat is
a. Emulsification
b. Enzyme action
c. Absorption by lacteals
d. Storage in adipose tissue
Answer:
a. Emulsification

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 9.
Enterokinase takes part in the conversion of
a. Pepsinogen into pepsin
b. Trypsinogen into trypsin
c. Protein into polypetide
d. Caseinogen into casein
Answer:
b. Trypsinogen into trypsin

Question 10.
Which of the following combinations are not matched?

Column – IColumn – II
a. Bilirubin and biliverdin(i) Intestinal juice
b. Hydrolysis of starch(ii) Amylases
c. Digestion of fat(iii) Lipases d Salivary gland
d. salivary gland(iv) Parotid

Answer:
a. Bilirubin and biliverdin – (i) Intestinal juice

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 11.
Match column I with column II and choose the correct option

Column – IColumn -II
P. Small intestinei. Largest factory
Q. Pancreasii. Absorption of water
R. Liveriii. Carrying electrolytic solution
S. Coloniv. Digestion and absorption

a. (P-iv) (Q-iii) (R-i) (S-ii)
b. (P- iii) (Q-ii) (R-i) (S-iv)
c. (P-iv) (Q-iii) (R-ii) (S-i)
d. (P-ii) (Q-iv) (R-iii) (S-i)
Answer:
a. (P-iv) (Q-iii) (R-i) (S-ii)

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 12.
Match column I with column II and choose the correct option

Column – IColumn -II
P. Small intestinei. 23 cm
Q. Large intestineii. 4 meter
R. Oesophagusiii. 12.5 cm
S. Pharynxiv. 1.5 meter

a. (P-iv) (Q- ii) (R- i) (S-iii)
b. (P- ii) (Q- iv) (R- i) (S-iii)
c. (P-i) (Q-iii) (R-ii) (S-iv)
d. (P-iii) (Q-i) (R-ii) (S-iv)
Answer:
b. (P- ii) (Q- iv) (R- i) (S-iii)

Question 13.
Match column I with column II and choose the correct option

Column – IColumn -II
P. Lipasei) Starch
Q. Pepsinii) Cassein
R. Reniniii) Protein
S. Ptyaliniv) Lipid

a. (P-iv) (Q-ii) (R-i) (S- iii)
b. (P- iii) (Q- iv) (R- ii) (S- i)
c. (P- iv) (Q- iii) (R-ii) (S- i)
d. (P- iii) (Q- ii) (R- iv) (S- i)
Answer:
c. (P- iv) (Q- iii) (R-ii) (S- i)

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 14.
Which of the following is not the function of the liver?
a. Production of insulin
b. Detoxification
c. Storage of glucogen
d. Production of bile
Answer:
a. Production of insulin

Question 15.
Assertion (A): Large intestine also shows the presence of a villi-like small intestine.
Reason (B): Absorption of water takes place in the large intestine
a. Both A and B are true and B is the correct explanation of A
b. Both A and B are true but B is not the correct explanation of A
c. A is true but B is false
d. A is false but B is true
Answer:
a. Both A and B are true and B is the correct explanation of A

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 16.
Which of the following is not true regarding intestinal villi?
a. They possess microvilli
b. They increase the surface area
c. They are supplied with capillaries and the lacteal vessels
d. They only participate in the digestion of fats
Answer:
d. They only participate in the digestion of fats

Question 17.
Which of the following combinations are not matched?
a. Vitamin D – Rickets
b. Thiamine – Beriberi
c. Vitamin K – Sterlity
d. Miacin – Pellagea.
Answer:
c. Vitamin K – Sterility

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 18.
Why are villi present in the intestine and not in the stomach?
Answer:
In the small intestine, digestion gets completed and the absorption of digested food materials like glucose, amino acids, fatty acids, and glycerol takes place. The food materials are to be retained in the intestine by increasing the surface area. Hence villi are present in the intestine. The stomach is the temporary storing organ of food. In the stomach, HCl, pepsin, renin, and lipase are secreted. These are concerned with digestion. Hence villi are not present in the stomach.

Question 19.
Bile juice contains no digestive enzymes. yet it is important for digestion. Why?
Answer:

  • The pile contains bile pigments (Bilirubin and biliverdin)
  • The pile pigments are broken down products of heamoglobin of dead RBC’s
  • Bile salts, cholesterol, and phospho lipids.
  • Bile has no enzyme.
  • Bile helps in the emulsification of fats.
  • Bile salts reduce the surface tension of fat droplets and break them into small globules.
  • Bile also activates lipase to digest lipids.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 20.
List the chemical changes that starch molecule undergoes from the time it reaches the small intestine.
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 1

Question 21.
How do proteins differ from fats in their energy value and their role in the body?
Answer:

ProteinLipid
1. The caloric value 5.65 Kcal/ gramThe caloric value 9.45 Kcal/gram
Q- Physiological fuel value 4 Kcal/gramPhysiological fuel value 9 Kcal/ gram

Question 22.
Digestive secretions are secreted only when needed discuss.
Answer:

  • The saliva is secreted by the salivary gland in the mouth Saliva
  • The saliva contains water.
  • Electrolytes – Na+, K+ , Cl, HCo3
  • Salivary amylase (ptyalin)
  • Mucus (a glycoprotein)
  • Polysaccharides, starch is hydrolyzed by the salivary amylase enzyme into disaccharides (maltose)

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 2

Stomach

  • The gastric j uice contains HCI and proenzymes
  • Proenzyme pepsinogen on exposure to HCI gets converted into active enzyme pepsin.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 3

  • The HCI provides an acidic medium (pH=1.8) which is optimum for pepsin, kills bacteria and other harmful organisms and avoids putrification.
  • Proteolytic enzyme found in gastric juice of Infants is rennin helps in the digestion of milk protein caseinogen to casein in the presence of calcium.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 4

Small Intestine

Pancreatic juice:
Enzymes: Trypsinogen, Chymotrypsinogen, Carboxypeptidases, Pancreatic, Amalyse, Pancreatic Lipase, and Nucleases.

Trypsinogen is activated by an enzyme enterokinase, secreted by the intestinal mucosa into active trypsin, which in turn activates the enzyme chymotrypsinogen in the pancreatic juice.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 5

Bile Juice:
The bile contains bile pigment (Bilirubin, and biliverdin) as the breakdown product of heamoglobin of dead RBCs, Bile salts, Cholesterol, and phospholipids. But has no enzymes. Bile helps in the emulsification of fats. Bile salts reduce the surface tension of fat droplets and break them into small globules, bile also activates lipases to digest lipids.

Pancreatic juice action:
Trypsin hydrolyses protein into polypeptides and peptones. While chymotrypsin hydrolyses peptide bonds associated with specific amino acids.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 6

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 7

Succus enterius:
The secretions of the Brunner’s gland along with the secretions of the intestinal glands constitute the intestinal juice or succus entericus.
Enzymes: Maltase, lactase, sucrase (invertase), dipeptidases, lipases, nucleosidases.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 8

Bicarbonate ions from the Pancreas provide an alkaline medium (pH=7.8) for the enzymatic action.
All macromolecules → Micromolecules
Carbohydrate → Monosaccharides
Protein → Aminoacid
Lipids → Fatty acids and Glycerol

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 23.
Label the given diagram.
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 9
A – Right hepatic duct of the liver
B – Common bile duct
C – Pancreatic duct (duct of wirsung)
D – Hepatopancreatic duct
E – Cystic duct

Part II

11th Bio Zoology Guide Digestion and Absorption Additional Important Questions and Answers

I. Choose The Best Option.

Question 1.
……………………… litres of digestive juice is poured into the alimentary canal and are reabsorbed each day.
a) 6 – 7 lit
b) 0 – 7 lit
c) 5-7 lit
d) 3 – 7 lit
Answer:
b) 0 – 7 lit

Question 2.
The Hard chewing surface of the teeth is made of ………………………… and helps in mastication of food.
a) Enamel
b) Crown
c) Denton
d) Plague
Answer:
a) Enamel

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 3.
Which is the correct statement?
a) Tongue is a freely movable muscular organ attached at the anterior end by the frenulum to the floor of the buccal cavity.
b) Tongue is a freely movable muscular organ not attached at the posterior end by the frenulum to the floor of the buccal cavity.
c) Tongue is a freely movable muscular organ attached at the posterior end by the frenulum to the floor of the buccal cavity.
d) Tongue is a freely movable muscular organ attached at the anterior, posterior end by the frenulum to the floor of the buccal cavity.
Answer:
c) Tongue is a freely movable muscular organ attached at the posterior end by the frenulum to the floor of the buccal cavity.

Question 4.
Which is the correct sequence?
a) Gullet → Glottis → Epiglottis
b) Epiglottis → Glottis → Gullet
c) Glottis → Gullet → Epiglottis
d) Gullet → Epiglottis → Glottis
Answer:
a) Gullet → Glottis → Epiglottis

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 5.
Which is a false statement?
a) Stomach divided into three region
b) Cardiac, fundic, pyloric regions
c) Pyloric region found between duodenum and jejunum
d) Cardiac region has a sphincter
Answer:
c) Pyloric region found between duodenum and jejunum

Question 6.
Find out the incorrect pair.
a) Starch – Amylase
b) Protein – Pepsin
c) Casein – Trypsin
d) Lipid – Lipase
Answer:
c) Casein – Trypsin

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 7.
Find out the correct pair
a) Duodenum – 25 m
b) Jejunum – 2.4 m
c) Ileum – 3.7 m
d) Oesophagus – 10 m
Answer:
b) Jejunum – 2.4 m

Question 8.
Which is a wrong statement
a) Brunner’s gland doesn’t secrete mucus and enzymes
b) Brunner’s gland secretes mucus and enzymes
c) It is found in duodenum
d) It is theopenningofcaecum
Answer:
a) Brunner’s gland doesn’t secrete mucus and enzymes

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 9.
Where is crypts of Leiberkuhn seen?
a) Small Intestine
b) Oesophages
c) Stomach
d) Rectum
Answer:
a) Small Intestine

Question 10.
The anal column may get enlarged and causes
a) Haemoralds
b) Haemorhoids
c) Elaemorods
d) Elaemorals
Answer:
b) Haemorhoids

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 11.
Find the correct statement
a) Serosa – The outer layer formed of connective tissue
b) Serosa – Connective tissue, epithelial tissue
c) Serosa – Connective tissue, striated cells
d) Serosa – Connective tissue, thin squanmous epithelium
Answer:
d) Serosa – Connective tissue, thin squanmous epithelium

Question 12.
Match the following
1. Parotid gland – i) Pepsin
2. Sub maxillary gland – ii) Stenson’s duct
3. Sublingual gland – iii) Wharton’s duct
4. Stomach – iv) Duct of Rivinis
a) (1-ii) (2-iii) (3-iv) (4-i)
b) (1-i) (2-ii) (3-iii) (4-iv)
c) (1-ii) (2-iii) (3-i) (4-iv)
d) (1-iii) (2-ii) (3-iv) (4-i)
Answer:
a) (1-ii) (2-iii) (3-iv) (4-i)

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 13.
Where is castle intrinsic factor secreted?
a) Intestine
b) Digestive passage
c) Stomach
d) Large intestine
Answer:
c) Stomach

Question 14.
The hepatic lobules are covered by …………………….. a thin connective tissue sheath.
a) Glisson’s capsule
b) Cardiac membrane
c) Renal membrane
d) Cystic membrane
Answer:
a) Glisson’s capsule

Question 15.
Find the correct statement. The differentiation of Liver
a) 4-5 week
b) 3-4 week
c) 4-7 week
d) 12-3 week
Answer:
b) 3-4 week

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 16.
Find the wrong statement
a) Saliva – Ptyalin
b) Digestive tract – Mucous membrane
c) Stomach – Pepsin
d) Small intestine – Glucokinase
Answer:
d) Small intestine – Glucokinase

Question 17.
What is pH of food at the time of absorption?
a) 7.3
b) 7.5
c) 7.8
d) 7.7
Answer:
c) 7.8

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 18.
True or false
a) Carbohydrate – Glucose
b) Protein – Aminoacid
c) Fat – Fatty acid
d) Bile – Pepsin
Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 32
Answer:-
a) True
b) True
c) False
d) False

Question 19.
Find x-part the diagram
Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 10
a) Common bile duct
b) Pancreatic duct
c) Jejunum
d) Gall bladder
Answer:
b) Pancreatic duct

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 20.
Find the correct pair.
a) Carbohydrate -50% -400-500 gm
b) Fat-15%65-75 gm
c) Carbohydrate -51 % 400 -450 gm
d) Fat-15% -70-75 gm
Answer:
a) Carbohydrate -50% -400-500 gm

Question 21.
Name the vitamin synthesized by bacteria of the large intestine
a) D
b) K
c) C
d) E
Answer:
b) K

Question 22.
Find the correct statement.
a) Unused protein – stored in the liver
b) Unused protein – stored in the muscle
c) Unused protein – excretes as nitrogen
d) Unused protein – excretes through faeces
Answer:
c) Unused protein – excretes as nitrogen

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 23.
What is the nature of food in the stomach?
a) Chyme
b) Fermented
c) Solid
d) Semisolid
answer:
a) Chyme

Question 24.
Which is the longest part of the digestive system?
a) Large intestine
b) Small intestine
c) Oesophages
d) Stomach
Answer:
b) Small intestine

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 25.
Where is pyloric muscle present?
a) Junction between oesophagus and stomach
b) Junction between the large intestine and small intestine
c) Junction between small intestine and stomach
d) Junction between large intestine and rectum
Answer:
c) Junction between small intestine and stomach

Question 26.
How much protein is needed for a day?
a) 1 gm per kg
b) 2 gm per kg
c) 1.5gmperkg
d) 2.5gmperkg
Answer:
a) 1 gm per kg

(2 marks)

II. Very Short Questions

Question 1.
What are the uses of food?
Answer:
The food we eat provides energy and organic substances for growth and the replacement of worn-out and damaged tissues. It regulates and coordinates the various activities that take place in the body.

Question 2.
What are the special features that help in absorbing digested food?
Answer:

  • There is an increase in the small intestine surface area.
  • The villi are present in the inner walls of the intestine.
  • The villi is the absorbtive unit
  • The microvilli present in the villi increase the absorptive surface.

Question 3.
Why do we need a digestive system?
Answer:
The food that we eat is macromolecules, and inabsorbable. These are to be broken down into smaller macro-molecules in absorbable forms. This is done by the digestive system.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 4.
How is fat and other nutrients of bile helped in digestion?
Answer:
It helps in emulsifying fat. The bile salt decreases the surface tension of fat molecules and converting it to chilo micron.

Question 5.
What is the function of the digestive system?
Answer:
The function of the digestive system is to bring the nutrients, water, and electrolytes from the external environment into every cell in the body through the circulatory system.

Question 6.
What happens when there is no secretion of HCI in the stomach?
Answer:

  • The HCI in the stomach coverts the inactivated pepsinogen into active pepsin.
  • The activated pepsin acts on protein and converts them into proteases and peptones
  • HCI provides an acidic medium which is optimum for pepsin action.

Question 7.
List out the processes starting from the ingestion of protein and storning in the muscle cells and converting them in to the parts of cytoplasm?
Answer:
Stomach:
The gastric juice contains pepsin. This is the first enzyme that works on protein.
Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 11

  • Rennin is present in the gastric juice of infants
  • It helps in the digestion of caesinogen and converts into casein.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 12

Pancreas:

  • Trypsin hydrolyses proteins in to polypeptides and peptones.
  • Chymotrypsin hydrolyses peptide bonds associated with specific amino acids.

Succus Entricus
The peptidases present in the intestinal juice convert the di and polypeptides to amino acids.
Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 13
The end product of digestion the amino acids that are absorbed by the villi and reach the blood.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 8.
What is diphyodont dentition?
Answer:
Human beings and many mammals form two sets of teeth during their lifetime, a set of 20 temporary milk teeth which gets replaced by a set of 32 permanent teeth. This type of dentition is called diphyodont dentition.

Question 9.
Why the food prepared in the house is better than the food which is prepared by causing preservative and artificial enhancers?
Answer:
The food prepared by using artificial enhancers and preservatives creates so many diseases.
Diseases

  • Heart problems
  • Hypertension
  • Sterility
  • Stomach disorders
  • Attainment of early puberty in girl children.

Question 10.
What is known as the dental formula of human beings?
Answer:
The arrangement of teeth in each half of the upper and lower jaw in the order of I, C, P, and M can be represented by the dental formula. The dental formula of man is 2123 / 2123.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 11.
What are the steps to be taken to care for our alimentary tract?
Answer:

  • We have to take healthy foods.
  • We have to take plenty of water.
  • We have to regulate our stress.
  • We have to take probiotics daily.
  • We have to do exercise daily.

Question 12.
What are the functions of soluble and insoluble fibres?
Answer:
The food contain two types of fibres.
Soluble fibre: It soaks up toxins and waste in the digestive system.
Insoluble fibre: Roughage. It moves bulk through the intestine to help with regular bowel movements.
This upper surface of the tongue has small projections called Papillae.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 13.
What is the function of the tongue?
Answer:
The tongue helps in the intake of food, chew and mix food with saliva, swallow food, and also speak. The upper surface of the tongue has small projections called papillae with taste buds.

Question 14.
What are Oesophages?
Answer:
Oesophages connect the buccal cavity and stomach.

Question 15.
What is gastro oesophagus reflux disorder?
Answer:
If the cardiac sphincter does not contract properly during the churning action of the stomach the gastric juice with acid may flow back into the oesophagus and cause heart bum, resulting in GERD (Gastro Oesophagus Reflex Disorder).

Question 16.
How larger food molecules are converted into small molecules?
Answer:

Large MoleculesSmall Molecules
1. CarbohydrateMonosaccharides – Glucose fructose Galactose
2. ProteinAmino acids
3. FatAmino acids

Question 17.
What are gastric rugae?
Answer:
The inner wall of the stomach has many folds called gastric rugae which unfold to accommodate a large meal.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 18.
What is meant by colities?
Answer:

  • The bacterial infection may cause inflammation of the innerlining of colon called colitis.
  • The most common symptoms of colitis are rectal bleeding abdominal cramps and diarrhoea.

Question 19.
What is indigestion?
Answer:

  • It is a digestive disorder in which the food is not properly digested leading to a feeling of fullness of stomach.
  • It may be due to in adequate enzyme secretion anxiety food poisoning overeating and spicy food.

Question 20.
Give notes on vomiting?
Answer:
It is reverse peristalsis. Harmful substances are ejected through the mouth. This action is controlled by the vomit centre located in the medulla oblongate a feeling of nausea precedes vomiting.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 21.
What is meant by digestion? What is the different processes of digestion?
Answer:
The break down of the macromolecules of food in to the micro molecules of food is known as digestion.
Stages

  1. Ingestion
  2. Digestion
  3. Absorption
  4. Assimilation
  5. Elimination of undigested substances digestion

Question 22.
What is Frenulum?
answer:
The tongue is attached at the posterior end to the floor of the buccal cavity by the structure frenulum and the tongue is free in the front.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 23.
What is meant by GERD – GASTERO oesophagus reflex disorder?
Answer:

  • There are two sphincter muscles namely cardiac sphincter and pyloric sphincter present in the stomach.
  • If the sphineter does not contract properly during the churning action of the stomach of the gastric juice with acid may flow back in to the oesophagus and cause heart bum resulting in GERD.

Question 24.
How is piles or haemorrhoides formed?
Answer:

  • The anal mucosa is folded into several vertical folds contains arteries and veins called anal columns.
  • if these anal columns get enlarged and causes piles or haemorrhoides.

Question 25.
Name the enzyme which converts the inactivated enzymes into the active enzyme.
Answer:
1. Enterokinase:
It converts the inactivated Trypsinogen in to Trypsin.

2. Trypsin:
The inactive chymotrypsinogen is converted into chymotrypsin
Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 25

Question 26.
What are the food components needed for a person for healthy living?
Answer:

  • Carbohydrates
  • Proteins
  • Lipids
  • Vitamin
  • Minerals
  • Fibre
  • Water

Question 27.
Define Thecodont?
Answer:
Each tooth is embedded in a socket in the jaw bone; this type of attachment is called thecodont.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 28.
What is meant by assimilation?
answer:
All the body tissues utilize the absorbed substances for their activities and incorporate in to their protoplasm this process is called assimilation.

Question 29.
Define Plaque.
Answer:
Minerals salts like Calcium and Magnesium are deposited on the teeth and form a hard layer of tartar or calculus called plaque.

Question 30.
What is Papillae?
Answer:
This upper surface of the tongue has small projections called Papillae.

Question 31.
What are the parts of Stomach?
Answer:

  • A cardiac portion
  • A fundic portion
  • A pyloric portion

Question 32.
What is the portion of small intestine?
Answer:
Duod enum – 25Cm
Jejunum-2.4m
Ileum-3.5m

Question 33.
What is Gastric rugae?
Answer:
The inner wall of the stomach has much folds called gastric rugae which unfolds to accommodate a large meal.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 34.
What are the parts of large Intestine?
Answer:

  • Caecum
  • Colon
  • Rectum

Question 35.
What are the regions of colon.
Answer:
The colon is divided into four region.

  1. An ascending region
  2. A Transverse region
  3. A Descending region
  4. A Sigmoid region

Question 36.
What are the layers found in the alimentary canal?
Answer:

  • Serosa
  • Muscularis
  • Sub – mucosa
  • Mucosa

Question 37.
What are the elements found in Saliva?
Answer:

  • Water
  • Electrolytes (Na+, K+, Cl, HCO3)
  • Salivary Amylase (Ptyalin)
  • Anti bacterial agent Lysozyme
  • Lubricating agent mucus (glycoprotein).

Question 38.
What are the components present in bile?
Answer:

  • Bilirubin
  • Biliverdin
  • Bile Salts
  • Cholesterol
  • Phospholipids

Question 39.
Name the gastric juices found in the stomach.
Answer:

  • Hydrochloric acid (PH 1.8)
  • Proenzyme – Pepsinogen
  • Pepsin Rennin

Question 40.
What is the function of Pyloric Sphincter?
Answer:

  • The opening of the stomach into the duodenum is guarded by the Pyloric Sphincter.
  • It periodically allows partially digested food to enter the duodenum and also prevents regurgitation of food.

Question 41.
What is the Calorific value of carbohydrates?
Answer:

  • The caloric value of Carbohydrates is 4.1 calories /gram.
  • The physiological fuel value is 4 Kcal / gram.

Question 42.
A person is suffering from a digestion problem. What may be the reason?
Answer:
This person may be suffering from constipation.
Constipation:
The faeces are retained within the rectum, because of irregular bowel movement due to poor intake of fibre in the diet and lack of physical activities.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 43.
What is oral hydration therapy?
Answer:
If there is more loss of water due to diarrhea dehydration may occur. Treatment is known as oral hydration therapy.
This involves drinking plenty of fluids sipping small amounts of water at a time interval to rehydrate the body.

Question 44.
Define Obesity.
Answer:
It is caused due to the storage of excess of body fat in adipose tissue.
It may induce hypertension, atherosclerotic heart disease and diabetes.

Question 45.
What is BMI Calculation?
Answer:
BMI is calculated as body weight in Kg, divided by the square of height in meter.
\(\mathrm{BMI}=\frac{\text { Body Weight in } \mathrm{Kg}}{\text { (Body Height) }^{2} \text { in meter }}\)
For example :
A person Weight = 50 Kg
Height = 1.6m
\(=50 / 1.6^{2}\)
BMI = 19.5

(3 marks)

III. Short Questions

Question 1.
Define Gingivitis?
Answer:
The plaque formed on teeth is not removed regularly, it would spread down the tooth into the narrow gap between the gums and enamel and cause inflammation, called gingivitis.
Symptoms;
It leads to redness and bleeding of gums and leads to bad smell.

Question 2.
What is Heterodont?
Answer:
The permanent teeth are of four different types (heterodont).
Incisors – Chisel like cutting teeth
Caniues – Dogger shaped tearing teeth
Premolar -Grinding Molar – Grinding and Crushing
\(\frac{2123}{2123} \times 2=\frac{16}{16}\)
Upper Jaw – 16 teeth
Lower Jaw – 16 teeth

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 3.
What are the signifance of Liver?
Answer:
1. Destroy aging and defective bloodcells.
2. Stored glucose in the form of glycogen or disperses glucose into the blood stream with the help of pancreatic hormones.
3. Stores fat soluble vitamins and iron.
4. Detoxifies toxic substances.
5. Involves in the synthesis of non – essential aminoacids and urea.

Question 4.
Explain about the protein deficiency disease.
Answer:
Protein Energy Malnutrition (PEM):

  • Marasmus
  • Kwarshiorkor Marasmus:
  • Children are suffering from diarrhoea Body becomes lean and weak
  • Reduced fat and muscle tissue with thin and folded skin.

Kwashiorkor:

  • Dry skin
  • Potbelly
  • Edema in the legs and face
  • Stunted growth
  • Changes in hair colour
  • Weakness and irritability

Question 5.
Name the digestive secretions.
Answer:

  • Salivary glands
  • Bile juice
  • Pancreatic juice Gastric juice Small Intestinal juice.

Question 6.
What are the types of Salivary glands and their ducts?
Answer:

GlandLocationDucts
1.ParotidsCheeksStenson’s duct
2. SubmandibularLower JawWharton’s duct
3. SublingualBeneath the tonguçBartholin’s duet (or) ducts of Rivinis
The daily secretion of Saliva from Saliva glands ranges from 1000 to 1500ml.

Question 7.
What are the cells of gastric gland and their Secretions?
Answer:

Gastric cells of glandsSecretion
1. Chief cells (or) Peptic cells (or) Zymogen cellsGastric enzymes
2. Goblet cellsMucus
3. Parietal (or) Oxyntic cellsHCI an intrinsic factor responsible for the absorption of vitamin B12 is called castle’s intrinsic factor.

Question 8.
Draw and label the layers of the alimentary canal.
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 14
A – Microvilli
B – Circular muscle
C – Mucous
D – Muscular layer

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 9.
Explain the protein deficiency diseases.
Answer:
Growing children require more amount of protein for their growth and development. Protein deficient diet during the early stage of children may lead to protein-energy malnutrition such as Marasmus and Kwashiorkor. Symptoms are dry skin, pot-belly, oedema in the legs and face, stunted growth, changes in hair colour, weakness, and irritability.

Marasmus is an acute form of protein malnutrition. This condition is due to a diet with inadequate carbohydrates and protein. Such children are suffering from diarrhea, the body becomes lean and weak (emaciated) with reduced-fat and muscle tissue with thin and folded skin.

Question 10.
What are the ill effects of adulteration of food?
Answer:

  • Food adulteration causes harmful effects in the form of head ache palpitations allergies, cancers.
  • It reduces the food quality common adulteration are addict onto citric acid to lemon juice.
  • Papaya seeds to pepper melamine to milk.

Question 11.
A person has diet control in particular time, he takes large amount of rice, curd, buttermilk and onion why? and write about it?
Answer:
Yes the person is suffering from Jaundice.
Jaundice:

  • It is the condition in which liver is affected and the defective liver fails to break down haemoglobulin and to remove bile pigments from the blood.
  • Deposition of these pigments changes the colour of eyes and skin yellow.
  • Jaundice is caused due to hepatitis Viral Infection

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 12.
What is the effects of crystallized cholesterol?
Answer:
The effects of crystallized cholesterol is Gall Stones.

Gall Stones:

  • Any alteration in the composition of the bile can cause the formation of stones in the gall bladder.
  • The stones are mostly formed of crystallized cholesterol in the bile.
  • The gall stone causes obstruction in the cystic duct, hepatic duct and also hepatopancreatic duct, causing pain, Jaundice and pancreatitis.

Question 13.
What is indigestion?
Answer:
It is a digestive disorder in which the food is not properly digested leading to a feeling of fullness of stomach. It may be due to inadequate enzyme secretion, anxiety, food poisoning, overeating and spicy food.

Question 14.
Writes notes on Peptic Ulcer.
Answer:

  • It refers to an eroded area of the tissue lining (Mucosa) in the stomach or duodenum.
  • A duodenal ulcer occurs in people in the age group of 25-45 years.
  • Gastric ulcer is more common in person above the age of 5üyears.
  • Ulcer mostly due to infections caused by the bacterium Helicobacter pylon.
  • It may be due to uncontrolled usage of aspirin or certain anti-inflammatory drugs.
  • It is caused due to smoking, alcohol, caffeine, and psychological stress.

Question 15.
What is a hiatus hernia or diaphragmatic hernia?
Answer:
It is a structural abnormality in which the superior part of the stomach protrudes slightly above the diaphragm. The exact cause of hiatus hernias is not known. In some people, injury or other damage may weaken muscle tissue, by applying too much pressure (repeatedly) on the muscles around the stomach while coughing, vomiting, and straining during bowel movement and lifting heavy objects.

Question 16.
Give notes on the stomach.
Answer:

  • Stomach functions as the temporary storage organ for food.
  • It consists of three parts cardiac fundic and pyloric stomach.
  • The oesophagus opens into a cardiac stomach and guarded by cardiac sphincter.
  • The pyloric stomach opens into duodenum and is guarded by the pyloric sphincter.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 15

  • It allows partially digested food to enter the duodenum and prevents regurgitation of food.
  • The inner walls of stomach has many folds which unfolds to accommodate a large meal.

Question 17.
Give short notes on intestinal villi?
Answer:

  • The ileal mucosa has numerous vascular projections called villi which are involved in the process of absorption.
  • The cells lining the villi produce numerous microscopic projections called microvilli giving a brush border appearance and increase the surface area enormously.
  • Along with villi the clear mucosa contain mucous secreting goblet cell and peyer patches which produce lymphocytes.
  • The wall of the small intestine bears crypts between the base of villi called crypts of leiberkuhn.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 16

Question 18.
Write a paragraph on peptic ulcers.
Answer:
It refers to an eroded area of the tissue lining (mucosa) in the stomach or duodenum. A duodenal ulcer occurs in people in the age group of 25 – 45 years. Gastric ulcer is more common in persons above the age of 50 years. An ulcer is mostly due to infections caused by the bacterium Helicobacter pylori. It may also be caused due to uncontrolled usage of aspirin or certain anti-inflammatory drugs. An ulcer may also be caused due to smoking, alcohol, caffeine, and psychological stress.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 19.
Give an account of the Pancreas.
Answer:

  • The Pancreatic is the second-largest gland in the digestive system which is a yellow coloured compound organ.
  • It consists of exocrine and endocrine cells.
  • It is situated between the limbs of the ‘U’ shaped duodenum.
  • The exocrine portion secretes trypsin, pancreatic lipase, amylase.
  • The islets of Langerhans cells of the pancreas secrete insulin and glucogen hormone.

Question 20.
Name the alimentary canal parts and the absorptive substance.
Answer:

OrganSubstances tube absorbed
1. MouthWater Simple Sugar
2. StomachAlcohol, Medicine, Simple Sugar
3. IntestineSimple Sugar, Amino acids, Fatty Acids, Glycerol
4. ColonMore Water, Minerals, Vitamins, Medicines

(5 marks)

IV. Essay Questions

Question 1.
Describe the structure of the large intestine with a diagram.
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 17

1. The Caecum:

  • It is a small blind pouch-like structure that opens into the colon and it possesses a narrow finger-like tubular projection called vermi form appendix.
  • Caecumand vermiform appendix is large in herbivorous animals and act as an important site for cellulose digestion with the help of symbiotic bacteria.

2. The Colon:
The colon is divided in to four regions an ascending transverse a descending part and a sigmoid Colon. The Colon is lined by dilations called haustra.

3. Sigmoid Colon:

  • ‘S’ shaped sigmoid colon opensinto the rectum.
  • The anus is guarded by two anal sphincter muscles. The anal mucosa is folded in to several vertical folds and contains arteries and veins called anal column.
  • Anal colomn may get enlarged and causes piles.

Question 2.
Describe the structure of liver with a diagram.
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 18

  • The liver is the largest gland in our body.
  • It is situated below the diaphragm.
  • The liver consists of two major left and right lobes and two minor lobes.
  • Each lobe has many hepatic lobules called a functional unit of liver and is covered by a thin connective sheath called Glissons capsule.
  • Liver cells secrete and is stored in gall bladder. The duct of gall bladder and the hepatic duct form the common bile duct.
  • The bile duct and the pancreatic duct joined to gether formed a common duct and opens into duodenum and is guarded by a sphincter of oddi.
  • Liver has high power of regeneration and liver cells are replaced by new ones every 3-4 weeks.

Question 3.
Describe the process of digestion in the mouth.
Answer:

  • The smell the sight and taste as well as the mechanical stimulation of food in the mouth trigger a reflex action that results in the secretion of saliva.
  • The mechanical digestion starts in the mouth by grinding and chewing of good.
  • The saliva contains water electrolytes like Na, K, C1, HCO3 salivary amylase or ptyalin antibacterial agent lysozyme and a lubrication agent mucus.
  • The saliva moistening lubricating and adhering the masticated food into a bolus.
  • The ptyalin in the saliva hydrolyzes 30% of the poly saccharide into disaccharides.
  • The bolus is passed into the pharynx and then into the oesophagus by swallowing or deglutition.
  • The bolus reaches the stomach by successive waves of muscular contraction called peristalsis.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 4.
Describe the process of digestion in the stomach
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 19

  • The secretion of gastric juice begins when the food is in the mouth.
  • The gastric juice contains HCI pepsinogen renin etc.
  • The HCI changes the pepsinogen into pepsin.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 26

  • Pepsin acts on protein and converts into proteoses and peptones.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 27

 

  • The HCI provides an acidic medium which is optimum for pepsin kills bacteria and other harmful organisms and avoids putrefaction.
  • The mucous and bicarbonates protect the stomach from acidic HCl.
  • The rennin converts the milk protein caesinogen to casein in the presence of calcium ions.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 28

Question 5.
Describe the process of digestion in the small intestine.
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 20
The bile pancreatic juice and intestinal juice the secretions released into the small intestine.

Bile:

  • The bile contains bile pigments bilirubin and biliverdin as the break down products of haemoglobin of  dead RBCs bile salts.
  • Bile helps in emulsification of fats Bile salts reduce the surface tension of the fat droplets and break them into small globules.
  • Bile also activates lipases to digest lipids.

Pancreas:

  • The pancreatic juice contains enzymes such as trypsinogen, Chymotrypsinogen.
  • Trypsinogen is activated by an enzyme enterokinase into active trypsin.
  • Trypsin activate the chymotrypsinogen into chymotrypsin.
  • Trypsin hydrolyses protein into polypeptides and peptones.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 21
Chymotrypsin hydrolyses peptide bonds associated with specific aminoacids.
The amylase converts glycogen and starch into maltose.
Lipase acts on tri glycerides and hydrolyes them into free fatty acid and mono glycerides.
Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 22

Succtts entricus:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 23

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 6.
What is meant by absorption? How is digested food absorbed in the digestive system?
Answer:
Absorption is a process by which the end product of digestion passes through the intestinal mucosa in to the blood and lymph.
Process of absorption:

1. Simple Diffusion:
Small amounts of glucose amino acids and chloride ions are absorbed by simple diffusion.

2. Facilitated Transport:
Fructose arc absorbed with the help of the carrier ions like Na.

3. Active Transport:
Aminoacids, Glucose and Sodium are absorbed by active transport.

4. Passive Transport:
Fatty acid are absorbed by the Lacteals of Villi.

Question 7.
What is the caloric value of carbohydrates, proteins and fats?
Answer:
We obtain 50% of energy from carbohydrates 35 % from fats and 15 % from proteins.
We require about 400 – 500 gm of carbohydrates. 60 – 70 gm of fat 65 to 75 gm of proteins per day.

Carbohydrate:
The caloric valve of Carbohydrate is 4.1 calories gram and its physiological fuel value is 4 Kcal per gram.

Lipid:
Fat hasa caloric valve of 9.45 KCal and a physiological fuel value of 9 KCal per gram.

Protein:
The caloric and physiological fuel value of one gram of protein are 5.65 Kcal and 4 KCal respectively.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption

Question 8.
What is meant by Hiatus hernia or Oesophagus Hernia
Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 24

  • It is a structural abnormality in which superior part of the stomach protrudes slightly above the diaphragm.
  • Applying toomuch pressure on the muscles around the stomach while coughing, vomiting and straining during bowel movement and lifting heavy object it may weaken the muscle tissues of stomach.
  • In some people injury or the damage may weaken muscle tissue.
  • Heart burn is common in this disease.
  • The stomach contents travel back into the oesophagus or even into oral cavity and causes pain in the centre of the chest due to the eroding nature of acidity.

Question 9.
Obesity – Explain.
Answer:

  • It is caused due to the storage of excess of body fat in adipose tissue.
  • Obesity may be genetic or due to excess intake of food endocrine and metabolic disorders.
  • Degree of obesity is assessed by body mass index (BMI).
  • A Normal BMI range for adult is 19 – 25 above 25 is obese.
  • BMI is calculated as body weight in Kg divided by the square of body height in metres.
  • For example a 50 Kg person with a height of 160 Cms would have a BMI of 19.5.
  • That is BMI \(=50 / 1.6^{2}\) = 19.5

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 29

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 30

Samacheer Kalvi 11th Bio Zoology Guide Chapter 5 Digestion and Absorption 31

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Bio Zoology Guide Pdf Chapter 4 Organ and Organ Systems in Animals Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

11th Bio Zoology Guide Organ and Organ Systems in Animals Text Book Back Questions and Answers

Part I

I. Choose The Best Options

Question 1.
The clitellum is a distinct part in the body of earthworm Lampito mauritii, it is found in?
a. Segments 13-14
b. Segments 14-17
c. Segments 12 -13
d. Segments 14-16
Answer:
b. Segments 14-17

Question 2.
Sexually, earthworms are
a. Sexes are separate
b. Hermaphroditic but not self – fertilizing
c. Hermaphroditic and self – fertilizing
d. Parthenogenic
Answer:
b. Hermaphroditic but not self – fertilizing

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 3.
To sustain themselves, earthworms must guide their way through the soil using their powerful muscles. They gather nutrients by ingesting organic matter and soil, absorbing what they need into their bodies. Say whether the statement is True or False: The two ends of the earthworm can equally ingest soil.
Answer:
a. True
b. False

Question 4.
The head region of Cockroach ……………….. pairs of …………….. and …………….. shaped eyes occur.
a. One pair, sessile compound and kidney shaped
b. Two pairs, stalked compound and round shaped
c. Many pairs, sessile simple and kidney shaped
d. Many pairs, stalked compound and kidney shaped
Answer:
a. One pair, sessile compound and kidney shaped

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 5.
The location and numbers of malpighian tubules in Periplaneta.
a. At the junction of midgut and hindgut, about 150.
b. At the junction of foregut and midgut, about 150.
c. Surrounding gizzard, eight.
d. At the junction of colon and rectum, eight.
Answer:
a. At the junction of midgut and hindgut, about 150.

Question 6.
The type of vision in Cockroach is
a. Three dimensional
b. Two dimensional
c. Mosaic
d. Cockroachdonot have vision
Answer:
c. Mosaic

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 7.
How many abdominal segments are present in male and female Cockroaches?
a. 10,10
b. 9,10
c. 8,10
d. 9,9
Answer:
d. 9,9

Question 8.
Which of the following have an open circulatory system?
a. Frog
b. Earthworm
c. Pigeon
d. Cockroach
Answer:
d. Cockroach

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 9.
Buccopharyngeal respiration in frog
a. is increased when nostrils are closed
b. Stops when there is pulmonary respiration
c. is increased when it is catching fly
d. stops when mouth is opened.
Answer:
b. Stops when there is pulmonary respiration

Question 10.
Kidney of frog is
a. Archinephros
b. Pronephros
c. Mesonephros
d. Metanephros
Answer:
c. Mesonephros

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 11.
Presence of gills in the tadpole of frog indicates that
a. fishes were amphibious in the past
b. fishes involved from frog -like ancestors
c. frogs will have gills in future
d. frogs evolved from gilled ancestor
Answer:
d. frogs evolved from a gilled ancestor

Question 12.
Choose the wrong statement among the following:
a. In earthworm, a pair of male genital pore is present.
b. Setae help in the locomotion of earthworms.
c. Muscular layer in the body wall of an earthworm is made up of circular muscles and longitudinal muscles
d. Typhlosole is part of the intestine of earthworms.
Answer:
d. Typhlosole is part of the intestine of earthworm.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 13.
Which of the following are the sense organs of Cockroach?
a. Antennae, compound eyes, maxillary palps, anal cerci
b. Antennae, compound eye, maxillary palps and tegmina
c. Antennae, ommatidia, maxillary palps, sternum and anal style.
d. Antennae, eyes, maxillary palps, and tarsus of walking legs and coxa
Answer:
a. Antennae, compound eyes, maxillary palps, anal cerci

(2 marks)

II. Very Short Questions

Question 14.
What characteristics are used to identify the earthworms?
Answer:
In gardens, earthworms can be traced by their fecal deposits known as worm castings on the soil surface.
The earthworms can be identified using the following characteristics:

  • Long and cylindrical narrow body.
  • Bilateral symmetry
  • It is light brown in colour with a purple tinge at the anterior end.
  • The division of the body into many segments or metameres.
  • The dorsal surface of the body is marked by a dark mid-dorsal line.
  • In mature worms, segments 14-17 may be found swollen with a glandular thickening of the skin called the clitellum.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 15.
What are earthworm casts?
Answer:
The undigested particles along with soil are passed out through the anus as worm castings or vermicasts.

Question 16.
How do earthworms breathe?
Answer:

  • There are no lungs and gills.
  • They respire through the body surface.
  • The surface blood vessel helps in gaseous exchange.

Question 17.
Why do you call cockroaches a pest?
Answer:
Cockroaches destroy food and contaminate it with their offensive odour. They are carriers of a number of bacterial diseases. The cockroach allergen can cause asthma in sensitive people.

Question 18.
Comment on the functions of alary muscles?
Answer:
The triangular muscles that are present on both side of the heart are responsible for blood circulation.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 19.
Name the visual units of the compound eyes of cockroach.
Answer:

  • The photoreceptors of the cockroach consist of a pair of compound eye on the dorsal surface of the head.
  • Each eye is formed of about 2000 simple eyes called the ommatidia.

Question 20.
How does the male frog attract the female for mating?
Answer:

  • The male frog has a pair of vocal sacs and a copulatory or nuptial pad on the ventral side of the first digit of each forelimb.
  • Vocal sacs produce croaking sound to attract females and nuptial pad is also helpful in mating.

Question 21.
Write the types of respiration seen in frogs.
Answer:
Frog respires on land and in the water by two different methods. In water, the skin acts as an aquatic respiratory organ (cutaneous respiration). Dissolved oxygen in the water gets exchanged through the skin by diffusion. On land, the buccal cavity, skin, and lungs act as the respiratory organs. In buccal respiration on land, the mouth remains permanently closed while the nostrils remain open.

The floor of the buccal cavity is alternately raised and lowered, so air is drawn into and expelled out of the buccal cavity repeatedly through the open nostrils. Respiration by the lungs is called pulmonary respiration. The lungs are a pair of elongated, pink-colored sac-like structures present in the upper part of the trunk region (thorax). Air enters through the nostrils into the buccal cavity and then to the lungs. During aestivation and hibernation, gaseous exchange takes place through the skin.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 22.
Differentiate between peristomium and prostomium in earthworms.
Answer:

PeristomiumProstomium
1. The mouth is present in the centre of the first segment of the body called peristomiumOverhanging the mouth is a small flap called the upperlip or prostomium.

Question 23
Give the location of clitellum and spermathecal openings in Lampito mauritii.
Answer:

  • Clitellum -14 -17 segment.
  • Spermatheca – There are three pairs of spermathecae lying in segments 6/ 7,7/ 8,8/9

Question 24.
Differentiate between tergum and a sternum.
Answer:

Tergum
1.The scierites of dorsal side of cockroach Sternum
Sternum
 The sclerites of ventral side of cockroach

Question 25.
Head of cockroach is called hypognathous. Why?
Answer:
The mouth parts of cockroach are directed downwards. The head is small, triangular lies at a right angle to the longitudinal body axis. Hence it is called hypognathous.

Question 26.
What are the components of blood in frogs?
Answer:
1. Plasma-60%
2. Red blood cells, white blood cells platelets 40 %

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 27.
Draw a neat labeled diagram of the digestives system of frog.
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 1

Question 28.
Explain the reproductive system of frog
1. Male reproductive organ:

  • There are pair of testes. Each test is attached with kidney and dorsal body wall with the peritoneal membrane mesorchium.
  • The vasa efferentia arises from each test is opened into the bladder canal and it communicates with the urinogenital duct that comes out of kidneys and opens into the cloaca.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 2

2. Female reproductive system:

  • It consists of paired ovaries attached to the kidney and dorsal body wall by folds of peritoneum called mesovarium.
  • Each oviduct opens into the body cavity at the anterior end by a funnel like opening called ostia and posteriority the oviducts dilated to form ovisac before they open into cloaca.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 3

  • Fertilization is external.
  • The eggs hatch into tadpoles.
  • Tadpole develops three pairs of gills.
  • The tadpole grows into an air-breathing carnivorous adult frog through a process metamorphosis.

Part II

11th Bio Zoology Guide Organ and Organ Systems in Animals Additional Important Questions and Answers

I. Choose The Best Options

Question 1.
We can locate the earth worm’s living area through ……………………….
a. Small hole in the ground
b. Worm costings
c. Debris
d. Excreta of cattle.
Answer:
b. Worm costings

Question 2.
The region between 14 – 17 segments in earthworm is called as …………………
a. Pygidium
b. Prostomium
c. Clitellum
d. Peristomium
Answer:
c. Clitellum

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 3.
What is the shape of the setae?
a. ‘S’ shaped
b. C shaped
c. Round shaped
d. Curved shaped
Answer:
a. ‘S’ shaped

Question 4.
Find the correct pair.
a. First segment -Clitellum
b. Last segment – Peristomium
c. 14-17 -Pygidium
d. Vascular fold -Typhlosole
Answer:
d. Vascular fold -Typhlosole

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 5.
In which segment the lateral hearts are situated?
a. 7-13
b. 6-13
c. 6-15
d. 7-15
Answer:
b. 6-13

Question 6.
Find out the correct statement
a. In male cockroach the reproductive sac lie anteriorily.
b. In female cockroaches chitinous plates gonapophyses are present around the female genital aperature.
c. In male cockroach the sternum of 10th segment have pair of anal cerci.
d. In the 12th segment anal styes are seen.
Answer:
b. In female cockroaches chitinous plates gonapophyses are present around the female genital aperature.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 7.
What is the length of lampito mauritii.
a. 80-210 mm
b. 85-350 mm
c. 80 – 220 mm
d. 80 – 200 mm
Answer:
a. 80-210 mm

Question 8.
The pale brown the purplish tinge colour of earthworm is due to the pigment
a. Haemolymph
b. Porphyrin
c. Choloroquin
d. Flaemoglobin
Answer:
b. Porphyrin

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 9.
In which segments the spermatheca are situated
a. 6-7 segments, 7-8 segments 8-9 segments
b. 6-7 segments, 8-9 segments 9-10 segments
c. 8-9 segments, 9-10 segments 10-11 segments
d. 7-8 segments, 8-9 segments 9-10 segments
Answer:
a. 6-7 segments, 7-8 segments 8-9 segments

Question 10.
Find out the wrong statement?
a. The wall of earthworm is thin and moist.
b. There are cuticle and epithelial layer.
c. The body cavity which lies between the digestive system and body wall does not act as a fluid-filled structure.
d. The coelomic fluid is alkaline and milky in nature.
Answer:
c. The body cavity which lies between the digestive system and body wall does not act as a fluid-filled structure.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 11.
Whether the following statement is correct or wrong. Justify.
a. In earthworm the digestive tract runs from the mouth to anus.
b. In earthworm the mouth is seen in the first segment.
c. In the second segment lies buccal cavity.
d. In the 3 – 4th segment lies the pharynx.
a. True, False, False, True
b. True, True, True, True
c. False, False, False, True
d. True, False, True, False
Answer:
b. True, True, True, True

Question 12.
The large complex molecules which consist of organic-rich soil eaten by earthworm with the help of digestive enzymes is converted into the simple absorptive unit is
a. Intestinal digestion
b. Digestion
c. Rectal digestion
d. Enzymatic digestion
Answer:
b. Digestion

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 13.
Find the odd one out.
The earthworm receptors are
a. Photoreceptors
b. Vision receptors
c. Taste receptors
d. Gustatory receptors
Answer:
b. Vision receptors

Question 14.
Which of the following is true with an excretory system of earthworm.
a. Nephridia
b. Nephron minute tubules
c. Nephridia – minute coiled tubules
d. Nephron – coiled tubule
Answer:
c. Nephridia – minute coiled tubules

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 15.
Apart from nephridia, there is specialised cell present in the intestinal walls.
a. Chlorogogen
b. Chloricgen
c. Chlorajan
d. Chlorojin
Answer:
a. Chlorogogen

Question 16.
What is the other name for the seminal funnel?
a. Ciliary
b. Ciliary rosettes
c. Ciliary flagella
d. Ciliary antennae
Answer:
b. Ciliary rosettes

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 17.
How many days are taken by the earthworm to complete its life cycle?
a. 70 days
b. 65 days
c. 69 days
d. 60 days
Answer:
d. 60 days

Question 18.
What is the fluid manure of earthworm consist of?
a. Vermicomposting
b. Vermiculture
c. Vermiwash
d. Earthworm manure
Answer:
c. Vermiwash

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 19.
Find out the unrelated one
a. Vermi compose
b. Vermin
c. Vermiculture
d. Vermi wash
Answer:
b. Vermin

Question 20.
Match and find out correct
I. Coxa – a. Thick
II. Trochanter – b. Long
III. Femur – c. Small
IV. Tibia – d. Large
a. I – a, II – b, III – c, IV – d
b. I-d, II-c, III-b, IV-a
c. I-a, II-c , III-d ,IV-b
d. I – b, II – a, III – c, IV – d
Answer:
b. I-d, II-c, III-b, IV-a

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 21.
Find out the wrong pair of cockroaches.
a. Tarsus – Podomeres
b. Genital opening Sclerites – Parametabolus
c. Sclerites of the dorsal side – Tergites
d. Sclerites of the ventral side – Sternites
Answer:
b. Genital opening Sclerites – Parametabolus

Question 22.
Find out the wrong pair of cockroaches.
a. Spiracles – Stigmata
b. Ostia – Colourless coelomic fluid
c. Ostia – Digestive system cockroach
d. Supra oesophageal ganglion – Brain
Answer:
c. Ostia – Digestive system cockroach

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 23.
Which is the ancient organism of insect?
a. Cockroach
b. Cricket
c. Grasshopper
d. Scorpion
Answer:
a. Cockroach

Question 24.
Cockroach belongs to …………………………………………… period about 320 million years ago.
a. Devonian
b. Carboniferous
c. Missisipian
d. Pensylvanian.
Answer:
b. Carboniferous

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 25.
One of the fastest moving land insect is the cockroach. What is it’s speed?
a. 6.4 km/hr
b. 5.0 km/hr
c. 5.4 km/hr
d. 6.5 km/hr
Answer:
c. 5.4 km/hr

Question 26.
Which makes the wings of insect?
a. Chitin
b. Pecten
c. Cellulose
d. Hemicellulose
Answer:
a. Chitin

(2 marks)

II. Very Short Questions

Question 1.
Name the earthworms of India.
Answer:

  • Lampito mauritii (Megascolex mauritii)
  • Perioynx excavatus
  • Metaphire posthuma (Pheretima Posthuma)

Question 2.
What are the regions of clitellum?
Answer:

  • Preclitellar region (1st – 13th segments)
  • Clitellar region (14th – 17th segment)
  • Post – Clitellar region (after 17th segment)

Question 3.
Name the structure that helps in locomotion where is it seen?
Answer:
Locomotion is effected through setae. In all the segments of the body except the first last and clitellum there is a ring of chitinous body setae.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 4.
What is the composition of the coelom of earthworms?
Answer:
The coelomic fluid is milky and alkaline. It consists of granulocytes or eleocytes amoebocytes, mucocytes and leucocytes.

Question 5.
Classify earthworms based on their ecological strategies.
Answer:

  • Earthworms are classified as epigeics, anecics and endogeics based on their ecological strategies.
  • Epigeics are the surface dwellers e.g., Perionyx excavaus and Eudrilus eugeniae.
  • Anecics are found in the upper layers of the soil e.g., Lampiro mauritii, Lumbricus terrestris.
  • Endogeics are found in deeper layers of the soil e.g., Octochaetona thursoni.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 6.
What are the mouthparts of the cockroach?
Answer:

  • Labrum (i) pair of mandibles Labrum (ii) pair of maxillae
  • Labium and hypopharynx or tongue.

Question 7.
Give notes on sclerites?
Answer:
In each segment, exoskeleton has hardened plates called sclerites, which are joined together by a delicate and elastic articular membrane or arthrodial membrane.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 8.
When is cockroach evolved?
Answer:
The cockroaches are ancient among all groups of insects dating back to the carboniferous period about 320 million years ago.

Question 9.
Name the five segments of the leg of the cockroach?
Answer:

  1. Coxa -Large
  2. Trochanter-Small
  3. Femur -Long and broad
  4. Tibia – Long and thick
  5. Tarsus -has five movable joints

Question 10.
Where are hepatic caeca seen in cockroaches?
Answer:
At the junctional region of the gizzard are eight finger-like tubular blind processes called hepatic caecae.

Question 11.
Trace the air paths of respiration.
Answer:
Spiracle trachea tracheoles Tissues.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 12.
Write a note on coelom of earthworm.
Answer;
A spacious body cavity called the coelom is seen between the alimentary canal and the body wall. The coelom contains the coelomic fluid and serves as a hydrostatic skeleton, in which the coelomocytes are known to play a major role in regeneration. immunity and wound healing. The coelomic fluid of the earthworm is milky and alkaline, which consists of granulocytes or cicocytes. amoebocytes, mucocytes and leucocytes.

Question 13.
What are the structures that is not present in frog?
Answer:
In frog there is no external ear neck and tail.

Question 14.
Give notes on chyme?
Answer:
Digestion of food takes place by the action of hydrochloric acid and gastric juices secreted from the walls of the stomach. This partially digested food is called as chyme.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 15.
What are the regions of nervous system?
Answer:
Central nervous system peripheral nervous system autonomous nervous system.

Question 16.
A cockroach produces nutritionally dense milk to feed their young ones. It may be considered as a superfood of the future. How?
Answer:

  1. It contains crystalline milk.
  2. It is synthesised by diploptera punctata.

Question 17.
What are the economic importance of frog?
Answer:

  • Frogs feed on insects and helps in reducing insect pest population.
  • Frogs are used in traditional medicine for controlling blood pressure and for antiaging properties.

Question 18.
What are the types of cockroach?
Answer:

  • American cockroach
  • Brown – banded cockroach
  • German cockroach
  • Oriental cockroach
  • Viviparous cockroach

Question 19.
Name the cells that helps in excretion of cockroach?
Answer:

  • Fat bodies
  • Nephrocytes
  • Cuticle
  • Urecose glands

Question 20.
Define uricotelic organism.
Answer:
The nitrogenous wastes are eliminated through uric acid. (Eg.) Hence cockroach excretes uric acid as a waste it is said to be uricotelic.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 21.
What is typhiosole?
Answer:

  • The dorsal wall of the intestine of earthworm is folded into the cavity as the typhiosole.
  • This fold contains blood vessels and increases the absorptive area of the intestine.

Question 22.
What are the glands seen in male reproductive system ?
Answer:

  • Mushroom-shaped gland
  • conglobate gland.

Question 23.
What is clitellum?
Answer:
In mature worms 14 – 17 segments may be found swollen with a glandular thickening of the skin called the clitellum. This helps in the formation of cocoon.

Question 24.
Where is spermathecal openings seen in the earthworm?
Answer:
They are lying inter segmentally between the grooves of the segments 6/7,7/S and 8/9.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 25.
Where is genital openings seen in the earthworm?
Answer:

  • The female genital aperture lies on the ventral side in the 14th segment.
  • A pair of male genital apertures are situated latero-ventrally in the 18th segment.

Question 26.
Name the body muscles of earthworm.
Answer:

  • Cuticle
  • Epidermis
  • Coelomic epithelium

Question 27.
Name the cells t at makes the epidermis?
Answer:

  • Supportive cells
  • Glandular cells
  • Basal cells
  • Sensory cells

Question 28.
What is the functions of coelomocytes of earthworm?
Answer:
Uses of coelomocytes

  1. Regeneration
  2. Immunity
  3. Woundhealing

Question 29.
Name the cells of coelom of earthworm
Answer:

  • Granulocytes or eleocytes
  • Amoebocytes
  • Mucocytes
  • Leucocytes

Question 30.
What are lateral hearts ?
Answer:
In the anterior part of body of earthworm the dorsal vessel is connected with the ventral vessel by eight pairs of commissural vessels or lateral hearts lying in the 6th – 13th segment.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 31.
Give notes on nephrostome.
Answer:
The mega nephridium of earthworm has an internal funnel like opening called the nephrostome which is fully ciliated.

Question 32.
What is chloragogen cell?
Answer:
Besides nephridia special cells on the coelomic wall of the intestine called chloragogen cells are present. They excrete nitrogenous wastes in the blood.

Question 33.
Whatisprotandrous?
Answer:

  • The two sex organs of earthworm mature at different times and hence self fertilisation is prevented.
  • The sperm develops earlier than the production of ova. This process is known as protandrous.
    It transmits the diseases like cholera, dysentery and tuberculosis hence it is known as vectors.

Question 38.
Whatishypognathous?
Answer:
The mouth parts of cockroach are directed downwards so its is hypognathous.

Question 39.
What is compound eyes?
Answer:
The head of cockroach bears a pair of large sessile and reniform compound eyes. Each eye is formed of about 2000 simple eyes called the ommatidia and the vision caused by the ommatidia is mosaic vision.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 40.
Name the segments of the legs of cockroach?
Answer:
There are five segments in the legs of cockroach.

  1. Coxa
  2. Trochanter
  3. Femur
  4. Tibia
  5. Tarsus

Question 41.
What is podomeres?
Answer:
The last segment of the leg tarsus has five movable joints called podomeres or tarsomeres.

Question 42.
Give notes on wings of cockroach?
Answer:
Cockroach has two pairs of wing. The first pair of wings protects the hind wings when rest is called elytra or tegmina. The second pair of wings used in flight.

Question 43.
Name the plates of the abdomen of cockroach?
Answer:
There are 10 segments in the abdomen. The sclerites of the dorsal side are called tergites.
The sclerites on the ventral side are called sternites and the sclerites on the lateral sides are called pleurites.

Question 44.
What are the sensory receptors seen in cockroach?
Answer:

  • Antenna
  • Compound eyes
  • Labrum
  • Mandibles
  • Labialpalps
  • Analcerci

Question 45.
Name the fat bodies of cockroach?
Answer:
Nephrocytes, Cuticle, Urecose glands.

Question 46.
What are the glands seen in the male cockroach?
Answer:

  • Mushroom shaped gland
  • Conglobate gland.

Question 47.
What is meant by paurometabolus?
Answer:

  • In cockroach the embryonic development occurs in the ootheca for 5-13 weeks.
  • The development of cockroach is gradual through nymphal stages. Hence it is called as paurometabolus.

Question 48.
What are pokilotherms?
Answer:
The organisms which change its temperature according to the temperature of the environment is known as pokilotherms.

Question 49.
What is nictitating membrane?
Answer:
The third eyelid of frog is nictitating membrane. It protects the eye.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 50.
What is cloaca?
Answer:
As the digestive excretory reproductive system opens commonly through a aperture this is called as cloaca.

Question 51.
What is spiracle?
Answer:
In cockroach the trachea open through 10 pairs of small holes called spiracles.

Question 52.
What is meant by chordotonal receptor?
Answer:
Chordotonal receptor is found on the anal cerci which are receptive to vibrations in air and land.

Question 53.
How can a earthwom senses its burrow?
Answer:
In the prostomium of earthworm there are thermal and chemical receptors with the help of this they can find it’s habitat.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 54.
Compare the respiration of human with the respiration of cockroach?
Answer:
In the respiratory system of cockroach there are spiracles and trachea. Each spiracles can open and close. During inspiration spiracles open. This oxygen enters into the haemocoel through spiracles and exchange of gases taking place.

Question 55.
List the very special features of cockroach.
Answer:

  • Cockroach can survive being submerged under water upto 45 minutes.
  • They hold their breath often to help regulate loss of water.

Question 56.
Cockroach can live without ahead? How?
Answer:
A cockroach can live for a week without its head. There is no connection between head and respiration. There is no nostrils and lungs.
The abdomen has 10 pairs of spiracles. These spiracles are communicated with the tracheoles and haemolymph and exchange of gases taking place.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 57.
Why is mosaic vision with less resolution in cockroaches ?
Answer:
The unit of compound eye is ommatidium. There are hundreds of ommatidia. Each ommatidium forms a image. Each image formed in all the ommatidia forms a vision. This image is a mosaic vision.

Question 58.
List the charcteristic features of order Aneura?
Answer:
Frogs and Toads have elongated hindlimbs. This helps in jumping, Frogs can live in water and on trees. Parental care is seen in few species.

Question 59.
Differentiate the compound eyes from simple eye.
Answer:

Compound eyeSimple eye
1. Formed of hundreds of small unitsSingle eye
2. Each ommatidium contains lens cornea retina and optic nerveOnly one lens cornea retina and optic nerve
3. Each ommatidium forms a separate image and forms a unclear mosaic visionA single image informed. The image is clear

Question 60.
Why three chambered heart of frog is not as efficient as the four chambered heart of birds and mammals?
Answer:

  • The heart of birds and mammals have four chambers. The oxygenated and deoxygenated blood is carried by separate blood vessels and transports to body parts and the purifying organ.
  • The frog has three chambered heart. The oxygenated and deoxygenated blood mixeshere. This mixed blood is reaching all the parts.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 61.
What is meant by cloaca a Common digestive and excretary opening ?
Answer:

  • In the elasmobranhs amphibians, reptiles egg laying mammals the faeces and urine pass through this opening.
  • This passage is also a genital passage for the deposition of sperm. This is called cloacal aperature.

Question 62.
Give notes on setae of earthworm?
Answer:

  • Earthworm have setae which are small hair like bristles. They are not composed of the same material as human hair.
  • They will be helpful in feeding mating and locomotion.

Question 63.
Give notes on intestinal caeca of earthworm?
Answer:
In 26th segment of metaphire posthuma a pair of cone shaped bulging is seen. It is known as intestinal caecum. This secretes amylolytic enzymes. This helps in starch digestion.

( 3 marks)

III. Short Questions

Question 1.
Based on their ecological strategies classify the earthworms?
Answer:

Ecological strataEarthworm type
1. Epigeics – up on the earthPerionyx excavatus
2. Anecics – out of the earthLampito mauritii
3. Endogeics – with in the earthOctohaetona thurstoni

Question 2.
Where is longest earthworm seen?
Answer:

  • Micro chaetus rappi is an African giant earthworm can reach a length of 6.7 meter (22 feet)
  • Drawida nilamburansis is a species of earthworm in Kerala reaches a maximum length upto 1 meter (3 feet).

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 3.
What is the significance of coelomic fluid of earthworm?
Answer:

  • In the coelomic fluid coelomocytes are present.
  • It helps in regeneration.
  • It helps in immunity and healing of wounds.

Question 4.
What are the sensory receptors seen in the earthworm?
Answer:

  • Photo receptors – Found on the dorsal surface of the body.
  • Gustatory – Sense of taste are found in the buccal cavity.
  • Tactile receptors Sense of touch
  • Chemo receptors Seen in the prostomium and the bodywall.
  • Thermo receptors

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 5.
Draw the diagram of nephridia of earthworm and name the parts.
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 4

Question 6.
What are the other name for sclerites ?
Answer:
On the basis of their location they gets their name.

  • Dorsal sclerites – Tergites
  • Ventral sclerites – Stemites
  • Lateral sclerites – Plurites

Question 7.
The cockroach can survive with out the head. Whether the statement is correct or wrong if it is so give reason?
Answer:
This statement is correct.
Reason:

  • A cockroach can live for a week without its head.
  • Due to their open circulatory system they breath through little holes on each of their body segment hence they are not dependent on the mouth or head to breath.

Question 8.
What are the parts of the nervous system ?
Answer:
Supraoesophagial nerve ganglion or brain sub- oesophagial ganglion – circum oesophageal connectives double ventral nerve cord.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 9.
What are the significance of nervous system.
Answer:

  • Brain or supra oesophageal ganglion or brain.
  • It acts as a sensory and an endocrine centre.
  • Sub – oesophageal ganglion
  • It acts as a motor centre controls the movements of the mouthparts legs and wings.

Question 10.
Give notes on ommatidia?
Answer:

  • The photo receptors of the cockroach consists of a pair of compound eyes at the dorsal surface of the head.
  • Each eye is formed of about 2000 simple eyes called ommatidia.

Question 11.
Give notes on ‘Mosaic vision’?
Answer:

  • The cockroach perceives the vision through each ommatidia. This vision is mosaic vision.
  • Though there is sensitivity but the vision is not a clear one.

Question 12.
Why is sexual dimorphism exhibited clearly during breeding season in frog?
Answer:

  • During breeding the sexual dimorphism is seen clearly.
  • The male frog has a pair of vocal sac and a ; nuptial pad on the ventral side of the first digit i of each fore limb.
  • Vocal sacs assist in amplifying the croaking sound of frog.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 13.
How will you classify the earthworm based on their living in relation to ecological strata?
Answer:

  1. Epigeics – Surface living (Eg.) Eudrilus eugeniae
  2. Anecics-Found in upper layers of the soil. (Eg.) Lampito mauritii.
  3. Endogeics – Found in deeper layers of the soil. (Eg.) Octochaetona thurstoni.

Question 14.
Give an account of respiratory system of earthworm?
Answer:

  • Earthworm has no special respiratory organ like lungs or gills.
  • Respiration takes place through the body wall.
  • The outer surface of the skin is richly supplied with blood capillaries which helps in the diffusion of gases.
  • Oxygen diffuses through the skin into the blood.
  • Carbondi-oxide from the blood diffuses out.
  • The skin is kept moist by mucous and coelomic j fluid and facilitates exchange of gases.

Question 15.
Give an account of nervous system of earthworm?
Answer:

  • The brain composed of bilobed mass of supra- pharyngeal ganglia. On the third segment j supra-pharyngeal nerve ganglion and on the 4th segment sub-pharyngeal nerve ganglion is seen.
  • The brain and the sub-pharyngeal ganglia are connected by a pair of cirum-pharyngeal connectives.
  • The double ventral nerve cord runs backward from the sub-pharyngeal ganglion.

Question 16.
What is the excretory organ of earthworm? What are its type?
Answer:
The nephridia is the excretory organ of earthworm
They are three types.

  1. Pharyngeal or tufted nephridia seen in 5-9 segments
  2. Micro nephridia or Integumentary nephridia seen 14 – 19th -segment.
  3. Mega nephridia or septal nephridia seen from 19th – last segment.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 17.
Give notes on vermiwash.
Answer:

  • Vermi wash is a liquid manure or plant tonic obtained from earthworm.
  • It is used as a foliar spray and helps to induce plant growth.
  • It is a collection of excretory products, mucus secretion micro nutrients from the soil organic molecules.

Question 18.
What is wormery or wormbin?
Answer:
Earth worm can be used for recycling of waste food leaf litter and biomass to prepare a good fertilizer in container is known as wormery or wormbin. It makes superior compost.

Question 19.
Give the systematic classification of earthworm?
Answer:

  • Phylum – Annelida
  • Class – Oligocheata
  • Order – Haplotaxida
  • Genus – Lampito
  • Species – Mauriitii

Question 20.
In which part of the cockroach’s body the sensory receptors are seen?
Answer:

ReceptorsOrgans
1. Thigmo receptorAntenna, maxillary paips and anal cerci
2. OlfactoryAntennae
3. GustatoryMaxillary paips labium
4. Thermo receptorsTarsal segments on the legs.
5. Chordotonal which responds to air or earth borne vibrationsAnal cerci

Question 21.
Give the systematic classification of frog?
Answer:

  • Phylum – Chordata
  • Class – Amphibia
  • Order – Aneura
  • Genus – Rana
  • Species – Hexatacdyla

Question 22.
Give the systematic classification of cockroach?
Answer:

  • Phylum – Arthropoda
  • Class – Insecta
  • Order – Orthroptera
  • Genus – Periplanata
  • Species – Americana

Question 23.
Give an account of exo skeleton of cockroach?
Answer:

  • The entire body is covered by a hard chitinous exoskeleton.
  • In each segment exoskeleton has hardened plates called sclerites which are joined together by a delicate and elastic articular membrane.
  • The sclerites of the dorsal side are called tergites. Ventral side are called sternites lateral side are called pleurites.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 24.
Give an account of mouth parts of cockroach?
Answer:

  • The appendages form the mouth parts which are of biting and chewing type.
  • These are mandibulate or orthopterus.

Mouth parts

  1. Labrum – Upperlip
  2. A pair of mandibles
  3. Pair of maxillae.
  4. Labium-Lower lip
  5. Tongue – Hypopharynx.

Question 25.
Name the digestive glands of cockroach.
Answer:

  • Salivary glands.
  • Hepatic caeca or entericcaeca

Question 26.
Draw the male frog with vocal sac and nuptial pad and marks the parts.
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 5

Question 27.
Give an account of buccal cavity of frog.
Answer:

  • The wide mouth opens into the buccal cavity.
  • On the floor of the buccal cavity lies a large muscular sticky tongue.
  • The tongue is attached in front and free behind.
  • The free edge of the tongue is forked.
  • A row of small and maxillary teeth is found on the inner region of the upper jaw.
  • Vomerine teeth are present one on each side of the internal nosteils.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 28.
Give an account of blood of frog ?
Answer:
60% of frog’s blood is plasma and 40% is red blood cells. The blood cells composed of red blood cells, white blood cells and platelets.
White blood cells

  1. Neutrophil
  2. Basophil
  3. Eosinophils
  4. Lymphocytes
  5. Monocytes

 ( 5 marks)

IV. Essay Questions

Question 1.
Describe the external features of the earthworm?
Answer:

  • Earthworm has along and cylindrical body.
  • It is 80-210 mm in length. It is light brown in colour.
  • The body is encircled by a large number of grooves which divides it into a number of compartments called segments ormetameres.
  • The mouth is found in the centre of the first segment of the body called the peristomium.
  • Overhanging the mouth is a small flab called prostomium.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 6

  • The 14 – 17th segments become swollen called clitellum.
  • There are pair of female genital opening in the 14th segment and pair of male genital opening in the 18th segment.
  • In the segments 6/7, 7/8, 8/9 lies the spermatheca.
  • In all the segments of the body except the first last and clitellum there is ring of chitinous body setae. They all involved in locomotion.
  • The last segments bear anus.

Question 2.
Give an account of digestive system of earthworm?
Answer:
1. The alimentary canal runs as a straight tube throughout the length of the body from the mouth to anus.
2. The mouth opens into the buccal cavity which occupies the 1st and 2nd segments.
3.  The thick muscular pharynx lies in the 3rd and 4th segment and is surrounded by the pharyngeal glands.
4. A small narrow oesophagus lies in the 5th segment and 6th segment contains muscular gizzardes. Which helps in grinding the soil and decaying leaves.
5. The intestine starts from the 7th segment and ’ continues upto the last segment.
6. The dorsal wall of the intestine is folded into the vascular cavity called typhlosole.
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 7

Question 3.
Describe the structure of circulatory system of earthworm?
Answer:

  • In earthworm closed type of blood vascular system is seen which contains blood vessels, capillaries and lateral hearts.
  • Two median longitudinal vessels run above and below the alimentary canal as dorsal and ventral vessels of the earthworm.
  • There are paired valves in the dorsal vessels which prevent the backward flow of the blood.
  • From 6 to 13 segments with the 8 pairs of commissural vessels which connects the dorsal and the ventral vessel called lateral hearts.
  • The blood is pumped from the dorsal vessel to the ventral vessel.

The blood glands present in the anterior segments of the earthworm produce blood cells and haemoglobin and gives red colour to the blood.
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 8

Question 4.
Describe the structure of reproductive system of earthworm ?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 9
Earth worm is a hermaphrodite organism the male and female reproductive organs are found in the same individual.

Male reproductive system:

  • Two pairs of testes are present in the 10th and 11th segments. The testes give rise to the germ cellor spermatogonia.
  • Two pairs of seminal funnels called ciliary rosettes are situated in the same segments as the testes. Three pairs of spermathecalies in the 7,8,9 segments.
  • The vas deferens arise from the ciliary rosettes run upto the 18th segment and open exterior through the male genital aperture which contains two pairs of penial setae.
  • A pair of prostate glands lie in the 18th and 19th segments.
  • The secretion of prostate cement the spermatozoa into a bundles of spermatophores.

Female reproductive system:

  • A pair of ovaries lying in the 13th segment. Ovarian funnels are present beneath the ovaries continue as a oviduct and opens in the 14th segment as a female genital opening. There are three pairs of spermathecae lie in the 7th, 8th and 9th segment.
  • They receive spermatozoa during copulation.
  • The two earthworm mate juxta position opposite gonadal openings and exchanging sperms mature egg cells in the nutritive fluid are deposited in the cocoons produced by the glands cells of the citellum which also collects the partner’s sperm from the spermathecae.
  • Fertilization and developments occurs in the cocoon.
  • After 3 weeks baby earthworm are released.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 5.
Give an account of locomotion of earthworm?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 10

  • The earthworm normally crawls with the help of their body muscles setae and buccal chamber. The outer circular and inner longitudinal muscle layers lies below the epidermis of the body wall.
  • The contraction of circular muscles make the body long and narrow while the longitudinal muscles make the body short and broad and hence due to the contraction of longitudinal muscle the earthworm moves.
  • The alternate waves of extensions and contractions are aided by the leverage afforded by the buccal chamber and setae.

Question 6.
Describe the morphological features of cockroach?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 11

  • Cockroach is a bilaterally symmetrical segmented animal which is divisible into head thorax and abdomen.
  • The entire body is covered with chitinous exo-skeleton.
  • Each segment consists of sclerites. The head is small and triangular and the mouth parts are directed downwards hence known as hypognathous. The head bears a pair of compound eye. Each compound eye is composed of unit of ommatidia.
  • The mouth parts are of mandibulatetype. It consists of labrum pair of mandibles a pair of maxillae labium and tongue.
  • The thorax consists of prothorax mesothorax and metathorax. Each thoracic segment bears a pair of walking legs.
  • Due to the presence of 3 pairs of leg they are called as hexapoda. Each leg consists of five segments they are coxa, trochanter femur tibia and tarsus.
  • It has two pairs of wings. It is called as tegmina or elytra. The wings arise from the mesothorax protects the hind wings when at rest. The second pair of wings arise from metathoraxa and used inflight.

Question 7.
Draw the diagram of mouth parts of cockroach ?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 12

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 8.
Describe the structure of digestive system of cockroach with a diagram ?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 13

The alimentary canal is divided into three regions namely foregut midgut and hindgut.

Foregut:

  • It includes pre-oral cavity mouth pharynx oesophagus and the posterior region contains crop.
  • The food is stored in the crop. The crop is followed by gizzard which have chitinous teeth helps in the grinding of the food particles.

Midgut:

  • At the junctional region of the gizzard are eight finger like tubular blind processes called the hepatic caecae or enteric caecae.
  • At the junction of midgut and hind gut lies 100 – 150 yellow coloured malphigian tubules. It excretes the nitrogenous wastes from the haemolymph.

Hindgut:

  • The hind gut is broader than the midgut.
  • It consists of ileum colon andrectum. The rectum opens out through anus.
    Digestive glands
    Salivary glands
    Hepatic caeca

Question 9.
Describe the structure of circulatory system of cockroach ?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 14

Cockroach has an open type of circulatory system.
The coelom is filled with haemolymph. Heart is an elongated tube with muscular wall lying mid dorsally beneath the thorax.
The heart consists of 13 chambers with ostia on either side.
The blood from the sinuses enter the heart through the ostia and is pumped anteriorilly to sinuses again. In each segment there is triangular muscle called alary muscles are seen. It is responsible for blood circulation.
There is a pulsatile vesicle lies at the base of each antenna also pumps blood.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 10.
Give an account of excretory system of cockroach?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 15

  • The malphighian tubules are the main excretory organs of cockroach which help in eliminating the nitrogenous wastes from the body in the form of uric acid. Excretion is uricotelic.
  • In addition fat body, nephrocytes cuticle and urecose glands are also excretory in function. The malpighian tubules are attached at the junction of midgut and hindgut. There are about 100-150 in number present in 6 – 9 bundles.
  • Each tubule is lined by glandular and ciliated cells and the waste is excreted out through the hindgut.
  • The glandular cells of malpighian tubules absorb water salts and nitrogenous wastes. The cells of the tubules reabsorb water and inorganic salts.
  • By the contraction of the tubules nitrogenous waste is pushed in to the ileum. The remaining waste with solid uric acid is exceeded along with the faecal matter.

Question 11.
Describe the structure of reproductive system of male cockroach?
Answer:

  • The male reproductive system consists of a pair of testes vasa deferentia an ejaculatory duct utricular gland phallic gland and the external genitalia.
  • A pair of 3 lobed testes lies on the 4th and 6th abdominal segments. The vas deferens opens into the male gonopore which lies ventral to anus.
  • The mushroom shaped gland is a large reproductive gland which opens into the anterior part of the ejaculatory duet.
  • The sperms are stored in the seminal vesicles as bundles of spermatophores. Surrounding the male genital opening are few chitinous structures called phallomeres or gonopophyses which help in copulation.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 16
Question 12.
Describe the structure of female reproductive system of cockroach?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 17

  • The female reproductive system consists of a pair of ovaries vagina genital pouch collaterial glands speromthecae and the external genitalia.
  • A pair of ovaries lie in the segmetn of 2nd and 6th abdominal segment. Each ovary is formed of eight ovarian tubules. Oviducts of each ovary unite into a common oviduct known as vagina which opens into the genital chamber.
  • A pair of spermathecae is present in the 6th segment and opens in to the genital pouch.
  • During copulation the ova descend to the genital chamber and fertilised by the sperm. The collateral gland secreta a hard case called ootheeca around the egg.
  • The ootheca is dropped to a crack or crevice of high relative humidity near a food source. The nymphs are released from this ootheca and they grows by moulting about 13 times to reach the adult form.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 13.
Describe the morphological features of frog?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 18

The body of frog is streamlined to help in swimming. Body is divided into head and trunk.

Head:

  • The head is triangular and has an apex which forms the snout.
  • The mouth is at the anterior end on the head contains pair of external nostrils, pair of eyes with unmovable upper eyelid movable lower eye lid which protects the eye.
  • The nictitating membrane protects the eye when the frog is underwater.
  • A pair of ear drum lies behind the eyes. There is no external ear neck and tail.

Trunk:

  • It bears a pair of fore limbs and a pair of hind limbs. The hind limbs are longer than the forelimbs. At the posterior end between the hind limbs is the cloacal aperture.
  • Fore limbs help to bear the weight of the body. It consists of upper arm fore arm and a hand. The hind limbs consist of thigh shank and foot.
  • Foot bears five long webbed toes and one small spot called the sixth toe cloacal aperture.
  • Fore limbs help to bear the weight of the body. It consists of upper arm fore arm anda hand.
  • The hind limbs consist of thigh shank and foot. Foot bears five long webbed toes and one small spot called the sixth toe.

Question 14.
Describe about the digestive system of frog?
Answer:
The digestive system extends from mouth to the cloaca.
Digestive tract organs:

  • The alimentary canal consists of the buccal cavity pharynx oesophagus duodenum ileum and the rectum which opens outside by the cloacal aperture.
  • The mouth opens into the buccal cavity.

Tongue:

  • On the floor of the buccal cavity lies a large muscular sticky tongue. The tongue is attached in front and free behind.
  • The free edge of tongue is forked.

Teeth:

  • A row of small and pointed maxillary teeth is found on the inner region of the upper jaw. Vomerine teeth are also present as two groups. One on each side of the internal nostrils.
  • The lower jaw is devoid of teeth. The mouth opens into the buccal cavity and then to esophagus through pharynx. Oesophagus opens into stomach
  • Stomach opens in to intestine then to rectum and finally to the cloaca. Liver, Pancresa are the structures of digestive system.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 15.
Describe the structure of the heart of frog ?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 19

  • The heart consists of three chamber. Two auricle and one ventricle. Heart is covered by pericardium. On the dorsal side of the heart is a triangular chamber called sinus venosus.
  • Truncus arteriosus is a thick walled structure which is obliquely placed on the ventral surface of the heart.
  • It divides into right and left aortic trunk. Each divides into carotid systemic and pulmocutaneous arteries.
  • The systemic trunk of each side is joined posteriorly to form the dorsal aorta. They supply blood to the posterior part of the body. The pulmo-cutaneous trunk supplies blood to lungs and skin.
  • The sinus venosus receives the deoxygenated blood from the pre and post venacava and delivers the blood to the right auricle.
  • The left auricle receives oxygenated blood through pulmonary vein.

Question 16.
Describe the structure of the respiratory system of frog?
Answer:

  • Frog respires on land and in the water by two different methods. In water the dissolved oxygen in the water gets exchanged through the skin by diffusion.
  • On land the buccal cavity skin and lungs act as the respiratory organ.

Buccal respiration:

  • Mouth remains permanently closed while the nostrils remain open. The floor of the buccal cavity is raised and lowered so air drawn into and expelled out of the buccal cavity repeatedly through the open nostrils.
  • A pair of elongated pink coloured sac like lungs are present in the upper part of the trunk.
  • Air enters through the nostrils into the buccal cavity and then to the lungs.

Question 17.
Describe the structure of the nervous system
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 20

  • The nervous system is divided into the central nervous system, peripheral nervous system and the autonomous nervous system.
  • Peripheral nervous system consists of 10 pairs of cranial nerves and 10 pairs of spinal nerves. The autonomous nervous system is divided into sympathetic and parasympathetic nervous system.
  • CNS consists of brain and spinal cord. Brain is covered with pia mater and dura mater. The brain is divided into forebrain mid brain and hind brain
  • Fore brain Consists of a pair of olfactory lobes and cerebral hemisphere and diencephalon. The olfactory lobes contain a small cavity called olfactory ventricle.
  • The midbrain includes two large optic lobes and has cavities called optic ventricles.
  • Hind brain consists of cerebellum and medulla oblongata. The medulla oblongata passes out through the foramen magnum and continues as spinal cord.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 18.
Draw the diagram of buccal cavity of frog and name the parts?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 21

Question 19.
Describe the locomotion of earthworm?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 22

  • The earthworm normally crawl with the help of their body muscles setae and buccal chamber.
  • The outer circular and inner longitudinal muscle layers lies below the epidermis of the body wall.
  • The contraction of circular muscles make the body long and narrow while the longitudinal muscle make the body short and broad and hence due to the contraction of longitudinal muscle the earthworm moves.
  • The alternate waves of extensions and contractions are aided by the leverage afforded by the buccal chamber and setae.

Question 20.
Tabulate the morphological differences between lampito mauritii and metaphire posthuma.
Answer:

CharactersLampito mauritiiMetaphire posthuma
1. Shape and sizeCylindrical
80 mm – 210 mm in length 3.5mm – 5.0 mm in width
Cylindrical
115 – 130 mm in length 5 mm in width
2. ColourationLight BrownDark Brown
3. Segmentation165-190 SegmentsAbout 140 Segments
4. Clitellum14th – 17th Segments (4)14th – 16th Segments (3)
5. Intestinal caecaAbsentPresent in 26th segment
6. Male genital pore18th segment18th segment
7. Female genital pore14th segment14th segment

Question 21.
Tabulate anatomical differences between lampitomaritii and metaphire posthuma
Answer:

CharactersLampito mauritiiMetaphire posthuma
1. Sperma thecal openingThree pairs 6/7, 7/8 and 8/9Four pairs 5/6, 6/7, 7/8 and 8/9
2. Pharynx3rd – 4th segmentRuns up to 4th Segment
3. Oesophagus5th segment8th segment
4. Gizzard6th segment8th – 9th segment
5. Intestine7th segment to anus15th segment to anus
6. Lateral hearts8 pairs from 6th  to 13th segments3 pairs from 7th to 9th segments
7. Pharyngeal  nephridia5th _ 9th segment4th – 6th segment
8. Micronephridia14th to last segment7th to last segment
9. Meganephridia19th to last segment15th to last segment

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 22.
Differentiate the male cockroach from female cockroach.
Answer:

CharactersMale cockroachFemale cockroach
1. AbdomenLong and narrowShort and broad
2. SegmentsIn the abdomen, nine segments are visibleIn the abdomen, seven segments are visible
3. Anal stylesPresentAbsent
4. Terga7th ter gum covers 8 th tergum7th ter gum covers 8 th and 9th terga
5. Brood pouchAbsentPresent
6. AntennaLonger in lengthShorter in length
7. WingsExtends beyond the tip of abdomenExtends up to the end of abdomen

23. Draw the life cycle of lampito mauritii.
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals 23

Samacheer Kalvi 11th Bio Zoology Guide Chapter 4 Organ and Organ Systems in Animals

Question 24.
Differentiate the frog from toad.
Answer:

CharactersFrogToad
1. FamilyRanidaeBuforudae
2. Body shapeSlenderMore Bulky
3. LegsLongerShorter
4. Webbed feetpresentAbsent
5. SkinSmooth and moist skinDry skin covered with wart like glands
6. TeethMaxillary and vomerine teeth.Teeth absent
7. Egg formationLays eggs in clustersLays eggs in strings

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Bio Zoology Guide Pdf Chapter 3 Tissue Level of Organisation Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

11th Bio Zoology Guide Tissue Level of Organisation Text Book Back Questions and Answers

Part I

I. Choose The Best Options.

Question 1.
The main function of the cuboidal epithelium is
a. Protection
b. Secretion
c. Absorption
d. Both (b) and (c)
Answer:
d. Both (b) and (c)

Question 2.
The ciliated epithelium lines the
a. Skin
b. Digestive tract
c. Gall bladder
d. Trachea
Answer:
d. Trachea

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 3.
What type of fibres are found in connective tissue matrix?
a. Collagen
b. Areolar
c. Cartilage
d. Tubular
Answer:
a. Collagen

Question 4.
Prevention of substances from leaking across the tissue is provided by
a. Tight junction
b. Adhering junction
c. Gap junction
d. Elastic junction
Answer:
a. Tight junction

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 5.
Non-shivering thermogenesis in neonates produces heat through
a. White fat
b. Brown fat
c. Yellow fat
d. Colourless fat
Answer:
b. Brown fat

Question 6.
Some epithelia are pseudostratified. What does this mean?
Answer:
Pseudostratified epithelial cells are columnar but unequal in size. Although the epithelium is single-layered yet it appears to be multilayered due to the fact that nuclei lie at different levels in different cells.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 7.
Differentiate white adipose tissue from brown adipose tissue
Answer:

White adipose tissueBrown adipose tissue
1. They have less number of Mitochondria.They have more numbers of mitochondria.
2. They store nutrientsIt is used to heat the bloodstream to warm the body.

Question 8.
Why blood is considered as a typical connective tissue?
Answer:
Blood is considered a typical connective tissue because it is the fluid connective tissue containing plasma, RBCs, WBCs, and platelets. It functions as the transport medium for the cardiovascular system carrying nutrients, nitrogenous wastes, and respiratory gases throughout the body.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 9.
Differentiate between elastic fibres and elastic connective tissue.
Answer:

Elastic FibresElastic connective tissue
1. It is found in the skin as the leathery dermis and forms fibrous capsules of organs such as kidneys bones and cartilages.This is present in tendons that attach skeletal muscles to bones and ligaments.
2. It allows recoil of tissues following stretching.It attaches one bone to another.
3. It maintains the pulsative flow of blood through the arteries and the passive recoil of lungs following inspiration.It is able to with stand tension exerted in many directions and provides structural strength.

Question 10.
Name any four important functions of epithelial tissue and provide at least one example of a tissue that exemplifies each function.
Answer:

FunctionsTissues
1. Protection Squamous epithelium. In heart lungs and blood vessels as a protective covering.
2. AbsorptionColumnar epithelium. (It lines the digestive track)
3. SecretionCuboidal and columnar epithelium. Salivary gland endocrine glands.
4. FilterationSquamous epithelium glomerulus.

Question 11.
Write the classification of connective tissue and their functions.
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation 1

Question 12.
What is an epithelium? Enumerate the characteristic features of different epithelia. Epithelial tissue is a sheet of cells that covers the body surface or lines the body cavity.
Answer:

Types of epitheliumCharacters
1. Squamous epitheliumMade up of single thin layer of flattened cells with irregular boundaries.
2. Cuboidal epitheliumMade up of single layer of cube-like cells.
3. Columnar epitheliumMade up of a single layer of tall cells with round to
oval nuclei at the base.
4. Ciliated epitheliumIt bears cilia on their free surfaces.
5. Nonciliated epitheliumThere is no cilia on the free surfaces of columnar
epithelium
6. Pseudostratified epitheliumColumnar but unequal in size
7. Compound epitheliumMade up of more than one layer of cells.

Part II

11th Bio Zoology Guide Tissue Level of Organisation Additional Important Questions and Answers

I. Choose The Best Options

Question 1.
What are the types of epithelium
a. Simple squamous epithelium
b. Simple cuboidal epithelium
c. Simple columnar epithelium
d. Stratified epithelium
Answer:
a. Simple squamous epithelium

Question 2.
Which one of the following is not the functions of the epithelium.
a. Protection
b. Absorption
c. Reproduction
d. Excretion
Answer:
c. Reproduction

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 3.
Find out the epithelium with irregular boundaries
a. Ciliated epithelium
b. Squamous epithelium
c. Columnar epithelium
d. Pseudostratified epithelium
Answer:
b. Squamous epithelium

Question 4.
Name the epithelium which helps in protection, absorption and secretion.
a. Pseudostratified epithelium
b. Compound epithelium
c. Cuboidal epithelium
d. Columnar epithelium
Answer:
a. Pseudostratified epithelium

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 5.
Name the tissue which have numerous mitochondria ?
a. Brown adipose tissue
b. White adipose tissue
c. Dense connective tissue
d. Loose connective tissue
Answer:
a. Brown adipose tissue

Question 6.
Match and find the correct answers
I. Ciliated epithelium – a. Outer skin
II. Ciliated epithelium – b. Heart
III. Squamous epithelium – c. Gall bladder
IV. Compound epithelium – d. Ureter
a. I – c, II – b, III – d, IV – a
b. I – b, II – c, III – d, IV – a
c. I – a, II – b, III – c, IV – d
d. I – d, II – c, III – b, IV – a
Answer:
d. I – d, II – c, III – b, IV – a

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 7.
Find out the wrong pair.
a. Exocrine glands – Saliva
b. Endocrine glands – Hormones
c. Ants – Adipocytes
d. Blood – Fluid connective tissue
Answer:
c. Ants – Adipocytes

Question 8.
Name the tissues present in osteocytes
a. Connective tissue
b. Bone tissue
c. Blood
d. Adipose
Answer:
b. Bone tissue

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 9.
What are myofibrils?
a. Minute fibrils of muscle fibres
b. Fibers of epithelial tissues
c. The end of nerve tissue
d. In cardiac muscles
Answer:
a. Minute fibrils of muscle fibres

Question 10.
Match and find the correct answer
I. Simple squamous epithelium – a. Respiratory tract
11. Simple Cuboidal epithelium – b. Intestine
III. Simple columnar epithelium – c. Kidney
IV. Ciliated epithelium – d. Alveoli
a. I – a, II – b, III – c, IV – d
b. I – d, II – c, III – b, IV – a
c. I – c, II – d, III – a, IV – b
d. I – a, II – c, III – b, IV – d
Answer:
b. I – d, II – c, III – b, IV – a

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

(2 marks)

II. Very Short Questions

Question 1.
Define tissues.
Answer:
Group of cells that are similar in structure and perform common or related functions are called tissues.

Question 2.
Define organ system?
Answer:
If two or more organs perform common physical and chemical functions they are called “organ systems”.

Question 3.
What are the four types of tissues?
Answer:
Simple epithelium:

  • It consists of a simple layer.
  • It helps in protection, absorption, filtration, excretion, secretion, and sensory reception.

Compound epithelium:

  • It is multilayered.
  • It provides protection against chemical and mechanical stresses.

Question 4.
What is epithelial tissue? What are its types?
Answer:
It is a sheet of cells that covers the body surface or lines the body cavity.
Types:

  1. Simple epithelium
  2. Compound epithelium

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 5.
What are the functions of epithelial tissues?
Answer:

  • Outer covering
  • Protection
  • Absorption
  • Excretion
  • Secretion

Question 6.
What is unicellular glandular epithelium?
Answer:
It consists of isolated glandular cells.
(Eg.) Goblet cells of the alimentary canal.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 7.
Based on the secretion how are exocrine glands classify?
Answer:

  1. Merocrine
  2. Holocrine
  3. Apocrine

Question 8.
Where are connective tissues originated from?
Answer:
Connective tissues originated from Mesoderm.
Types of connective tissue: Bones and blood, Cartilage.

Question 9.
What are the functions of connective tissue?
Answer:

  • Binding
  • Support
  • Protection
  • Insulation
  • Transportation

Question 10.
What are the fibres present in the connective tissues?
Answer:

  • Collagen
  • Elastic
  • Reticular

Question 11.
What is meant by myofibrils?
Answer:
Each muscle is made of many long cylindrical fibers arranged in parallel arrays known as myofibrils.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 12.
What are involuntary muscles?
Answer:
Smooth muscles are involuntary as their functions cannot be directly controlled. (Eg.) Blood vessels, Stomach intestine

Question 13.
What is the unit of nervous system and name the tissues which made the nervous system?
Answer:
The unit of nervous system is neuron. Cells:

  • Excitable cells
  • Neuroglial cells.

Question 14.
What is the function of compound stratified epithelium and where is it seen?
Answer:
Uses:
Protection, secretion and absorption.

Site of occurrence:
Ciliated epithelium — Respiratory tract. Nonciliated epithelium – Epididymis urethra of male.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 15.
What is meant by tissue fluid? What is its composition?
Answer:
The areolar connective tissue acts as a reservoir of water and salts for the surrounding body tissue. Hence it is called tissue fluid.
Composition:

  • Fibroblasts
  • Macrophages
  • Mast cells

Question 16.
What is Ehler’s Danlos syndrome?
Answer:
Defect in the synthesis of collagen in the joints heart values organ walls and arterial walls.

Question 17.
What is stickler syndrome?
Answer:
It is a defect which affects collagen and results in facial abnormalities.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 18.
What is Rhabdo Myo sarcoma?
Answer:
It is a life-threatening soft tissue tumour of head neck and urinogenital tract.

Question 19.
What is Rheumatoid arthritis?
Answer:
The immune cell attack and inflame the membranes around the joints.

Question 20.
What is Sjogren’s syndrome?
Answer:
It is a disease in which progressive inability to secrete saliva and tears.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 21.
What is Palmaris muscle?
Answer:
It is a long narrow muscle run from the elbow to the wrist and is important for hanging and climbing in primates.

Question 22.
What is Parkinson’s disease?
Answer:
It is a degenerative disorder of the nervous system that affects movement often including tremors.

Question 23.
What is Alzheimer’s disease?
Answer:
It is a chronic neurodegenerative disease which includes the symptoms of difficulty in remembering recent events.

Question 24.
What is Biopsy?
Answer:
It is an examination of tissue or liquid removed from a living body to discover presence cause or extent of a disease.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 25.
What is an autopsy?
Answer:
It is a dissection of a dead body (Post – mortem) examination to discover the cause of death or the extent of disease.

Question 26.
What is Forensic science?
Answer:
It is the field of science that effectively uses histological techniques to trace out crimes.

Question 27.
The multicellular epithelium helps protect and prevent friction. What is special about the unicellular epithelium
Answer:
The unicellular epithelium is made up of a single layer of cells. These are seen in the organs which do the functions of absorption secretion and filtration.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 28.
What is acinus?
Answer:
It is the unit of secretion.

Question 29.
What are adipocytes?
Answer:
This is composed of big adipose tissue in the centre and the cytoplasm is seen as a thin covering layer.

Question 30.
What is the substrate of bone tissue?
Answer:
The mineral hydroxyapatite is a substrate of bone tissue.

(3 marks)

III. Short Questions 

Question 1.
Explain the types of simple epithelium.
Answer:
Simple epithelium is a simple layered sheet of cells that covers the body surface or lines the body cavity.
Types:
1. Squamous epithelium:
It is made of flattened cells with irregular boundaries. It is found in glomeruli, air sacs of lungs, the lining of heart, blood vessels.

2. Cuboidal epithelium:
It is made of cube-like cells. It is found in kidney tubules, ducts, and glands. It is important for secretion and absorption.

3. Columnar epithelium:
It is made of column-like cells. It lines the digestive tract. It is important for secretion and absorption.

4. Ciliated epithelium:
It has cilia at the free end. It is found in bronchi, uterine tubes. It is helpful in propelling materials.

5. Glandular epithelium:
Cuboidal or columnar epithelium specialized for secretion is called the glandular epithelium. E.g., goblet cells and salivary gland.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 2.
Compare dense regular connective tissue with dense irregular connective tissues?
Answer:

Dense regular connective tissueDense irregular connective tissue
1.Collagen fibres are present.Collagen fibres are present.
2. Fibroblast cells are present.Fibroblast cells are present.
3. it connects the bone with skeletal muscles,It is able to withstand tension exerted in many direction and provides structural strength.

Question 3.
Classify the muscles and their location?
Answer:
Muscles are of three types.

  1. Skeletal muscles
  2. Smooth muscles
  3. Cardiac muscles.

1. Skeletal muscles:
These muscle fibres are bundled together in a parallel fashion.
Location: They are closely attached to skeletal
bones.

2. Smooth muscles:
These fibres are tapered at both ends and do not show striations.
Location: Blood vessels stomach intestine.

3. Cardiac Muscles:
In this muscles, cell junction fuse the plasma membranes of cardiac muscle cells and make them stick together.
Location: Heart.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 4.
Explain compound epithelium.
Answer:

  • The compound epithelium is made up of multilayered cells.
  • These protect organs against chemical and mechanical stresses.
  • These cover the dry surface of the skin, the moist surface of the buccal cavity, pharynx, inner lining of ducts of salivary glands, and pancreatic ducts.

(5 marks)

IV. Essay Questions

Question 1.
What is glandular epithelium? Describe its types?
Answer:
Some of the epithelial cells get specialized for secretion they are called the glandular epithelium.
I. Based on cellular structure
They are classified as Unicellular (Eg.) Goblet cells of the alimentary canal. Multicellular (Eg.) Salivary gland

II. Based on mode of pouring
Exocrine glands – The products are released through ducts. (Eg.) Mucus secreting glands, Saliva secreting glands.
Endocrine glands – They do not have ducts. Their secretions directly secreted into the fluid bathing the glands.
(Eg.) Pituitary gland.

a) Exocrine glands based on cellular nature

  •  Unicellular
  • Multicellular

b) Exocrine based on the structure

  •  Simple
  • Compound glands

c) Based on their secretary units

  • tubular
  • alveolar
  • tubulo alveolar

d) Based on their mode of secretion

  • Merocrine
  • Holocrine
  • Apocrine.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 3 Tissue Level of Organisation

Question 2.
What is meant by compound gland? What are its uses and its types?
Answer:
It is made up of more than one layer of cells.

Uses:
It helps in providing protection against chemical and mechanical stresses.

Location:
Buccal cavity, Pharynx salivary glands, Pancreatic ducts

Types:

  • Stratified squamous epithelium. It is present in the dry epidermis of the skin,
  • Keratinized type-Mouth and vagina.
  • Non – Keratinized type
  • Stratified cuboidal epithelium – Sweat glands, Mammary gland
  • Columnar epithelium-Pharynx urethra
  • Transitional epithelium – Ureters, urinary bladder.

Question 3.
Explain the types of muscle.
Answer:
Each muscle is made of long, cylindrical fibres. They are composed of fine fibrils called myofibrils. Muscle fibres contract and relax. Skeletal muscle is attached to skeletal bones. It is striped or striated. It is a voluntary muscle. The smooth muscle fibres are fusiform and do not have striations. It is an involuntary muscle. Cardiac muscle tissue is present in the heart. It is striated and branched and involuntary.

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Chemistry Guide Pdf Chapter 9 Solutions Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Chemistry Solutions Chapter 9 Solutions

11th Chemistry Guide Solutions Text Book Back Questions and Answers

Textbook Evaluation:

I. Choose the best answer:

Question 1.
The molality of a solution containing 1.8 g of glucose dissolved in 250 g of water is
a) 0.2 M
b) 0.01 M
c) 0.02 M
d) 0.04 M
Answer:
d) 0.04 M

Question 2.
Which of the following concentration terms is / are independent of temperature
a) molality
b) molarity
c) mole fraction
d) a and b
Answer:
d) a and b

Question 3.
Stomach acid, a dilute solution of HCl can be neutralized by reaction with aluminium hydroxide Al(OH)3 + 3HCl (aq) -> AlCl3 + 3H2O. How many milliliters of 0.1 M Al(OH)3 solution is needed to neutralize 21 ml of 0.1 M HCl?
a) 14 mL
b) 7 mL
c) 21 mL
d) none of these
Answer:
b) 7 mL

Question 4.
The partial pressure of nitrogen in air is 0.76 atm and its Henry’s law constant is 7.6 × 104 atm at 300 K. What is the mole fraction of nitrogen gas in the solution obtained when air is bubbled through water at 300 K ?
a) 1 × 10-4
b) 1 × 104
c) 2 × 10-5
d) 1 × 10-5
Answer:
d) 1 × 10-5

Question 5.
The Henry’s law constant for the solubility of Nitrogen gas in water at 350 K is 8 × 104 atm. The mole fraction of nitrogen in air is 0.5. The number of moles of Nitrogen from air dissolved in 10 moles of water at 350 K and 4 atm pressure is
a) 4 × 10-4
b) 4 × 104
c) 2 × 10-2
d) 2.5 × 10-4
Answer:
d) 2.5 × 10-4

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 6.
Which one of the following is incorrect for an ideal solution?
a) ∆Hmix = 0
b) ∆Umix =0
c) ∆P = Pobserved – Pcalculated by Raoults law = 0
d) ∆Gmix = 0
Answer:
d) ∆Gmix = 0

Question 7.
Which one of the following gases has the lowest value of Henry’s law constant?
a) N2
b) He
c) CO2
d) H2
Answer:
c) CO2

Question 8.
P1 and P2 are the vapour pressures of pure liquid components, 1 and 2 respectively of an ideal binary solution If x1 represents the mole fraction of component 1, the total pressure of the solution formed by 1 and 2 will be
a) P1 + x1 (P2 – P1)
b) P2 – x1 (P2 + P1)
c) P1 – x2(P1 – P2)
d) P1 + x2(P1 – P2)
Answer:
c) P1 – x2(P1 – P2)

Question 9.
Osomotic pressure (π) of a solution is given by the relation
a) π = nRT
b) πV = nRT
c) πRT = n
d) none of these
Answer:
b) πV = nRT

Question 10.
Which one of the following binary liquid mixtures exhibits positive deviation from Raoults law?
a) acetone + chloroform
b) water + nitric acid
c) HCl + water
d) ethanol + water
Answer:
d) ethanol + water

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 11.
The Henry’s law constants for two gases A and B are x and y respectively. The ratio of mole fractions of A to B 0.2. The ratio of mole fraction of B and A dissolved in water will be
a) \(\frac{2 x}{y}\)

b) \(\frac{y}{0.2 x}\)

c) \(\frac{0.2 x}{y}\)

d) \(\frac{5 x}{y}\)
Answer:
d) \(\frac{5 x}{y}\)

Question 12.
At 100°C the vapour pressure of a solution containing 6.5g a solute in 100g water is 732 mm. If Kb = 0.52, the boiling point of this solution will be
a) 102°C
b) 100°C
c) 101°C
d) 100.52°C
Answer:
c) 101°C

Question 13.
According to Raoults law, the relative lowering of vapour pressure for a solution is equal to
a) mole fraction of solvent
b) mole fraction of solute
c) number of moles of solute
d) number of moles of solvent
Answer:
b) mole fraction of solute

Question 14.
At same temperature, which pair of the following solutions are isotonic?
a) 0.2 M BaCl2 and 0.2 M urea
b) 0.1 M glucose and 0.2 M urea
c) 0.1 M NaCl and 0.1 M K2SO4
d) 0.1 M Ba(NO3)2 and 0.1 M Na2SO4
Answer:
d) 0.1 M Ba(NO3)2 and 0.1 M Na2SO4

Question 15.
The empirical formula of a non – electrolyte (X) is CH2O. A solution containing six grams of X exerts the same osmotic pressure as that of 0.025 M glucose solution at the same temperature. The molecular formula of X is
a) C2H4O2
b) C8H16O8
c) C4H8O4
d) CH2O
Answer:
b) C8H16O8

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 16.
The KH for the solution of oxygen dissolved in water is 4 × 104 atm at a given temperature. If the partial pressure of oxygen in air is 0.4 atm, the mole fraction of oxygen in solution is
a) 4.6 × 103
b) 1.6 × 104
c) 1 × 10-5
d) 1 × 105
Answer:
c) 1 × 10-5

Question 17.
Normality of 1.25 M sulphuric acid is
a) 1.25 N
b) 3.75 N
c) 2.5 N
d) 2.25 N
Answer:
c) 2.5 N

Question 18.
Two liquids X and Y on mixing gives a warm solution. The solution is
a) ideal
b) non-ideal and shows positive deviation from Raoults law
c) ideal and shows negative deviation from Raoults Law
d) non-ideal and shows negative deviation from Raoults Law
Answer:
d) non-ideal and shows negative deviation from Raoults Law

Question 19.
The relative lowering of vapour pressure of a sugar solution in water is 2.5 × 10-3. The mole fraction of water in that solution is
a) 0.0035
b) 0.35
c) 0.0035/18
d) 0.9965
Answer:
d) 0.9965

Question 20.
The mass of a non – volatile solute (molar mass 80 g mol-1) which should be dissolved in 92g of toluene to reduce its vapour pressure to 90%
a) 10 g
b) 20 g
c) 9.2 g
d) 8 g
Answer:
d) 8 g

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 21.
For a solution, the plot of osmotic pressure (π) versus the concentration (c in mol L-1) gives a straight line with slope 310 R where ‘R’ is the gas constant. The temperature at which osmotic pressure measured is
a) 310 × 0.082 K
b) 310° C
c) 37°C
d) \(\frac{310}{0.082}\) K
Answer:
c) 37°C

Question 22.
200 ml of an aqueous solution of a protein contains 1.26 g of protein. At 300 K, the osmotic pressure of this solution is found to be 2.52 × 10-3 bar. The molar mass of protein will be (R = 0.083 L bar mol-1 K-1}
a) 62.22 kg mol-1
b) 12444 g mol-1
c) 300 g mol-1
d) None of these
Answer:
a) 62.22 kg mol-1

Question 23.
The Van’t Hoff factor (i) for a dilute aqueous solution of the strong electrolyte barium hydroxide is
a) 0
b) 1
c) 2
d) 3
Answer:
d) 3

Question 24.
Which is the molality of a 10% w/w aqueous sodium hydroxide solution?
a) 2.778
b) 2.5
c) 10
d) 0.4
Answer:
b) 2.5

Question 25.
The correct equation for the degree of an associating solute, ‘n’ molecules of which undergoes association in solution, is
a) α = \(\frac{\mathrm{n}(\mathrm{i}-1)}{\mathrm{n}-1}\)

b) α2 = \(\frac{n(1-i)}{(n-1)}\)

c) α = \(\frac{\mathrm{n}(\mathrm{i}-1)}{1-\mathrm{n}}\)

d) α = \(\frac{\mathrm{n}(1-\mathrm{i})}{\mathrm{n}(1-\mathrm{i})}\)
Answer:
c) α = \(\frac{\mathrm{n}(\mathrm{i}-1)}{1-\mathrm{n}}\)

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 26.
Which of the following aqueous solutions has the highest boiling point?
a) 0.1 M KNO3
b) 0.1 M Na3PO4
c) 0.1 M BaCl2
d) 0.1 M K2SO4
Answer:
b) 0.1 M Na3PO4

Question 27.
The freezing point depression constant for water is 1.86° K Kg mol-1. If 5 g Na2SO4 is dissolved in 45 g water, the depression in freezing point is 3.64°C. The Vant Hoff factor for Na2SO4 is
a) 2.57
b) 2.63
c) 3.64
d) 5.50
Answer:
a) 2.57

Question 28.
Equimolal aqueous solutions of NaCl and KCl are prepared,. If the freezing point of NaCl is -2°C, the freezing point of KCl solution is expected to be
a) -2°C
b) -4°C
c) -1°C
d) 0°C
Answer:
a) -2°C

Question 29.
Phenol dimerises in benzene having van’t Hoff factor 0.54. What is the degree of association?
a) 0.46
b) 92
c) 46
d) 0.92
Answer:
d) 0.92

Question 30.
Assertion:
An ideal solution obeys Raoults Law.
Reason:
In an ideal solution, solvent – solvent as well as solute – solute interactions are similar to solute-solvent interactions.
a) both assertion and reason are true and reason is the correct explanation of assertion
b) both assertion and reason are true but reason is not the correct explanation of assertion
c) assertion is true but reason is false
d) both assertion and reason are false
Answer:
a) both assertion and reason are true and reason is the correct explanation of assertion

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

II. Write brief answer to the following questions:

Question 31.
Define:
(i) Molality
(ii) Normality
Answer:
(i)Molality :
Molality (m) is defined as the number of moles of the solute dissolved in one kilogram (Kg) of the solvent. The units of molality are moles per kilogram, i.e., mole kg-1. The molality is preferred over molarity if volume of the solution is either expanding or contracting with temperature.
molality (m) = \(\frac{\text { Number of mole of solute }}{\text { mess of solvent in } \mathrm{kg}}\)

ii) Normality:
Normality (N) of a solution is defined as the number of gram equivalents of the solute present in one liter of the solution. Normality is used in acid-based redox titrations.
Normality (N) = \(\frac{\text { Number of gram equivalents of solute }}{\text { Volume of solution in litre }}\)

Question 32.
a) What is a vapour pressure of liquid?
Answer:
“The pressure exerted by the vapors above the liquid surface which is in equilibrium with the liquid at a given temperature is called vapor pressure”.

b) What is a relative lowering of vapour pressure?
Answer:
The relative lowering of vapour pressure is defined as the ratio of lowering of vapour pressure to the vapour pressure
of pure solvent (P0) RLVP = \(\frac{p^{0}-P}{P^{0}}\)

Question 33.
State and explain Henry’s law.
Answer:
“The partial pressure of the gas in vapor phase (vapour pressure of the solute) is directly proportional to the mole fraction (x) of the gaseous solute in the solution at low concentrations”. This statement is known as Henry’s law.
Henry’s law can be expressed as,
Psolute α xsolute in solution
Psolute = KH xsolute solution
Here, Psolute represents the partial pressure of the gas in vapour state which is commonly called as vapour pressure. Xsolute in solution represents the mole fraction of solute in the solution. KH is a empirical constant with the dimensions of pressure.

Question 34.
State Raoult law and obtain expression for lowering of vapour pressure when nonvolatile solute is dissolved In solvent.
Answer:
In an ideal solution, the vapour pressure of the solution is decreased when a non-volatile solute is dissolved in a solvent. The magnitude of decrease in the vapour pressure of the solution depends on the amount of solute added.
Let us consider the solution with the following features.
Mole fraction of the solvent = xA
Mole fraction of the solute = xB
Vapour pressure of the pure solvent = P°A
Vapour pressure of solution = P
As the solute is nonvolatile, the vapour pressure of the solution is only due to the solvent. Therefore, the vapour pressure of the solution (P) will be equal to the vapour pressure of the solvent (PA) over the solution.
i.e., P = PA
According to Raoult’s law, the vapour pressure of solvent over the solution is equal to the product or its vapour pressure in a pure state and its mole fraction.
PA = P°A xA or
P = P°A xA

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 35.
What is molal depression constant? Does it depend on nature of the solute?
Answer:
If m = 1 then ∆Tf = Kf
“Then Kf is equal to the depression in freezing point for 1 molal solution”. No, it does not depends on nature of the solute.

Question 36.
What is osmosis?
Answer:
“The phenomenon of the flow of solvent through a semipermeable membrane from pure solvent to the solution is called osmosis”. Osmosis can also be defined as “the excess pressure which must be applied to a solution to prevent the passage of solvent into it through the semipermeable membrane”. Osmotic pressure is the pressure applied to the solution to prevent osmosis.

Question 37.
Define the term ‘isotonic solution’.
Answer:
Two solutions having same osmotic pressure at a given temperature are called isotonic solutions.

Question 38.
You are provided with a solid. ‘A’ and three solutions of A dissolved in water – one saturated, one unsaturated, and one supersaturated. How would you determine which solution is which?
Answer:
(A) Unsaturated solution:
It can dissolve salt an additional to it.
(B) Saturated solution:
Further solubility of salt does not takes place but solubility can takes place on heating.
(c) Supersaturated solution:
Solubility of salt do not takes place on even an further heating.

Question 39.
Explain the effect of pressure on the solubility.
Answer:
Generally, the change in pressure does not have any significant effect in the solubility of solids and liquids as they are not compressible. However, the solubility of gases generally increases with increase of pressure.

Consider a saturated solution of a gaseous solute dissolved in a liquid solvent in a closed container. In such a system, the following equilibrium exists.
Gas                      ⇌     Gas
(in gaseous state) (in solution)

According to Le-Chatelier principle, the increase in pressure will shift the equilibrium in the direction which will reduce the pressure. Therefore, more number of gaseous molecules dissolves in the solvent and the solubility increases.

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 40.
A sample of 12 M Concentrated hydrochloric acid has a density 1.2 M gL-1 calculate the molality.
Solution:
Given:
Molarity = 12 M HCl
density of solution = 1.2 g L-1
In 12 M HCl solution, there are 12 moles of HCl in 1 litre of the solution.
Molality = \(\frac{\text { no of moles of solute }}{\text { mass of solvent (in } \mathrm{kg} \text { ) }}\)
Calculate mass of water(solvent)
mass of 1 litre HCl solution = density × volume
= 1.2 × gmL-1 × 1000 mL = 1200 g
mass of HCl = no. of moles of HCl × molar mass of HCl
= 12 mol × 36.5 g mol-1
= 438 g.
mass of water = mass of HCl solution – mass of HCl
mass of water = 1200 – 438 = 762 g
molality(m) = \(\frac{12}{0.762}\) = 15.75 m

Question 41.
A 0.25 M glucose solution, at 370.28 K has approximately the pressure as blood does what is the osmotic pressure of blood?
Solution:
C = 0.25 M
T = 370.28 K
(π)glucose = CRT
(π) = 0.25 mol L-1 × 0.082L atm K-1mol-1 × 370.28K
= 7.59 atm

Question 42.
Calculate the molality of a solution containing 7.5 g glycine(NH2-CH2-COOH) dissolved in 500g of water.
Solution:
Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions 1

Question 43.
Which solution has the lower freezing point? 10 g of methanol (CH3OH) in 100g g of water (or) 20 g of ethanol (C2H5OH) in 200 g of water.
Solution:
∆Tf = Kf i.e
∆Tf α m
mCH3-OH = \(\frac{\left(\frac{10}{32}\right)}{0.1}\)
= 3.125 m

mC2H5-OH = \(\frac{\left(\frac{20}{46}\right)}{0.2}\)
= 2.174 m

∴ Depression in freezing point is more in methanol solution and it will have lower freezing point.

Question 44.
How many moles of solute particles are present in one liter of 10-4 M potassium sulphate?
Answer:
In 10-4 M K2SO4 solution, there are 10-4 moles of potassium sulphate.
K2SO4 molecule contains 3 ions (2K+ and 1 SO42-)
1 mole of K2SO4 molecule contains 3 × 6.023 × 1023 ions
10-4 mole of K2SO4 contains 3 × 6.023 × 1023 × 10-4 ions
= 18. 069 × 1019

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 45.
Henry’s law constant for solubility of methane in benzene is 4.2 × 10-5 mm Hg at a particular constant temperature. At this temperature calculate the solubility of methane at
i) 750 mm Hg
ii) 840 mm Hg.
Solution:
(KH)benzene = 4.2 × 10-5 mm
Solubility of methane =?
P = 750 mm Hg P = 840 mm Hg
According to Henrys Law,
P = KH Xin solution
750 mm Hg = 4.2 × 10-5 mm Hg. Xin solution
⇒ Xin solution = \(\frac{750}{4.2 \times 10^{-5}}\)

i. e solubility = 178. 5 × 105
similarly at P = 840 mm Hg
solubility = \(\frac{840}{4.2 \times 10^{-5}}\) = 200 × 10-5

Question 46.
The observed depression in freezing point of water for a particular solution is 0.093°C calculate the concentration of the solution in molality. Given that molal depression constant for water is 1.86 K Kg mol-1.
Solution:
∆Tf = 0.093°C = 0.093 K, m = ?
Kf = 1.86 K Kg mol-1
∆Tf = Kf.m
∴ m = \(\frac{\Delta \mathrm{T}_{\mathrm{f}}}{\mathrm{K}_{\mathrm{f}}}=\frac{0.093 \mathrm{~K}}{1.86 \mathrm{~K} \mathrm{Kg} \mathrm{mol}^{-1}}\)
= 0.05 mol Kg-1 = 0.05 m

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 47.
The vapour pressure of pure benzene (C6H6) at a given temperature is 640 mm Hg. 2.2 g of non – volatile solute is added to 40 g of benzene. The vapour pressure of the solution is 600 mm Hg. Calculate the molar mass of the solute?
Solution:
P°C6H6 = 640 mm Hg
W2 = 2.2 g (non volatile solute)
W1 = 40 g (benzene)
Psolution = 600 mm Hg
M2 =?
Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions 2

11th Chemistry Guide Solutions Additional Questions and Answers

I. Choose the best answer:

Question 1.
6.02 × 1020 molecules of urea ate present in 200 ml of its solution, The concentration of urea solution is (N0 = 6.02 × 1023 mol-1)
a) 0.001 M
b) 0.01M
c) 0.02 M
d) 0.10 M
Answer:
c) 0.02 M

Question 2.
Calculate the molarity and normality of a solution containing 0.5 g of NaOH dissolved in 500 ml solution
a) 0.0025 M, 0.025 N
b) 0.025 M, 0.025 N
c) 0.25 M, 0.25 N
d) 0.025M, 0.0025 N
Answer:
b) 0.025 M, 0.025 N

Question 3.
5 ml of N HCl, 20 ml of N/2 H2SO4 and 30 ml of N/3 HNO3 are mixed together and volume made to one liter. The normality of the resulting solution is
a) \(\frac{\mathrm{N}}{40}\)

b) \(\frac{\mathrm{N}}{10}\)

c) \(\frac{\mathrm{N}}{20}\)

d) \(\frac{\mathrm{N}}{5}\)
Answer:
a) \(\frac{\mathrm{N}}{40}\)

Question 4.
At 25°C, the density of 15 M H2SO4 is 1.8 g cm-3. Thus, mass percentage of H2SO4 in aqueous solution is
a) 2%
b) 81.6%
c) 18%
d) 1.8%
Answer:
b) 81.6%

Question 5.
Mole fraction of C3H5(OH)3 in a solution of 36 g of water and 46 g of glycerine is :
a) 0.46
b) 0.36
c) 0.20
d) 0.40
Answer:
c) 0.20

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 6.
The molality of a urea solution in which 0.0100 g of urea, [(NH2)2CO] is added to 0.3000 dm3 of water at STP is
a) 0.555 m
b) 5.55 × 10-4
c) 33.3 m
d) 3.33 × 10-2 m
Answer:
b) 5.55 × 10-4

Question 7.
15 grams of methyl alcohol is dissolved in 35 grams of water. What is the mass percentage of methyl alcohol in solution?
a) 30%
b) 50%
c) 70%
d) 75%
Answer:
a) 30%

Question 8.
A 3.5 molal aqueous solution of methyl alcohol (CH3OH) is supplied. What is the mole fraction of methyl alcohol in the solution?
a) 0.100
b) 0.059
c) 0.086
d) 0.050
Answer:
b) 0.059

Question 9.
In which mode of expression of concentration of a solution remains independent of temperature?
a) Molarity
b) Normality
c) Formality
d) Molality
Answer:
d) Molality

Question 10.
Calculate the molarity of pure water (d = 1 g/L)
a) 555 M
b) 5.55 M
c) 55. 5 M
d) None
Answer:
c) 55. 5 M

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 11.
Calculate the quantity of sodium carbonate (anhydrous) required to prepare 250 ml solution
a) 2.65 grams
b) 4.95 grams
c) 6.25 grams
d) None of these
Answer:
a) 2.65 grams

Question 12.
Find the molality of H2SO4 solution whose specific gravity is 1.98 g ml-1 and 95 % by volume H2SO4
a) 7.412
b) 8.412
c) 9.412
d) 10.412
Answer:
c) 9.412

Question 13.
Calculate molality of 1 liter solution of 93 % H2SO4 by volume. The density of solution is 1.84 g ml-1
a) 9.42
b) 10.42
c) 11.42
d) 12.42
Answer:
b) 10.42

Question 14.
Calculate the molality and mole fraction of the solute in aqueous solution containing 3.0 g of urea per 250 gm of water (Mol.wt. of urea = 60).
a) 0.2 m, 0.00357
b) 0.4 m, 0.00357
c) 0.5 m, 0.00357
d) 0.7 m, 0.00357
Answer:
a) 0.2 m, 0.00357

Question 15.
Calculate normality of the mixture obtained by mixing 100 ml of 0.1 N HCl and 50 ml of 0.25 N NaOH solution.
a) 0.0467 N
b) 0.0367 N
c) 0.0267 N
d) 0.0167 N
Answer:
d) 0.0167 N

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 16.
300 ml 0.1 M HCl and 200 ml of 0.03 M H2SO4 are mixed. Calculate the normality of the resulting mixture
a) 0.084 N
b) 0.84 N
c) 2.04 N
d) 2.84 N
Answer:
a) 0.084 N

Question 17.
What weight of oxalic acid (H2C2O4.2H2O) is required to prepare, 1000mL of N/10 solution?
a) 9.0 g
b) 12.6 g
c) 6.3 g
d) 4.5 g
Answer:
c) 6.3 g

Question 18.
Which of the following units is useful in relating concentration of solution with its vapour pressure?
a) Mole fraction
b) Parts per million
c) Mass percentage
d) Molality
Answer:
a) Mole fraction

Question 19.
The pressure under which liquid and vapour can co-exist at equilibrium is called the
a) Limiting vapour pressure
b) Real vapour pressure
c) Normal vapour pressure
d) Saturated vapour pressure
Answer:
b) Real vapour pressure

Question 20.
CO(g) is dissolved in H2O at 30°C and 0.020 atm. Henry’s law constant for this system is 6.20 × 104 atm. Thus, mole fraction of CO(g) is
a) 1.72 × 10-7
b) 3.22 × 10-7
c) 0.99
d) 0.01
Answer:
b) 3.22 × 10-7

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 21.
H2S gas is used in qualitative analysis of inorganic cations. Its solubility in water at STP is 0.195 mol kg-1. Thus, Henry’s law constant ( in atm raolaT1) for H2S is
a) 2.628 × 10-4
b) 5.128
c) 0.185
d) 3.826 × 103
Answer:
b) 5.128

Question 22.
Which of the following is correct for a solution showing positive deviations from Raoult’s law?
a) ∆V = +ve, ∆H = + ve
b) ∆V = -ve, ∆H = – ve
c) ∆V = + ve, ∆H = -ve
d) ∆V = – ve, ∆H = +ve
Answer:
a) ∆V = +ve, ∆H = + ve

Question 23.
If liquids A and B form an ideal solution
a) The entropy of mixing is zero
b) The Gibbs free energy is zero
c) The Gibbs free energy as well as the entropy of mixing are each zero
d) The enthalpy of mixing is zero
Answer:
d) The enthalpy of mixing is zero

Question 24.
Water and ethanol form non – ideal solution with positive deviation from Raoult’s law. This solution, will have vapour pressure
a) equal to vapour pressure of pure water
b) less than vapour pressure of pure water
c) more than vapour pressure of pure water
d) less than vapour pressure of pure ethanol
Answer:
c) more than vapour pressure of pure water

Question 25.
Which of the following is less than zero for ideal solutions?
a) ∆Hmix
b) ∆V
c) ∆Gmix
d) ∆Smix
Answer:
c) ∆Gmix

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 26.
Which of the following shows negative deviation from Raoult’s law?
a) CHCl3 and CH3COCH3
b) CHCl3 and C2H5OH
c) C6H5CH3 and C6H6
d) C6H6 and CCl4
Answer:
a) CHCl3 and CH3COCH3

Question 27.
Given at 350 K, P°A = 300 torr and P°B = 800 torr, the composition of the mixture having a normal boiling point of 350 K is :
a) XA = 0.08
b) XA = 0.06
c) XA = 0.04
d) XA = 0.02
Answer:
a) XA = 0.08

Question 28.
In mixture A and B, components show – ve deviation as :
a) ∆Vmix is + ve
b) A – B interaction is weaker than A – A and B – B interaction
c) ∆Hmix is + ve
d) A – B interaction is stronger than A – A and B – B interaction
Answer:
d) A – B interaction is stronger than A – A and B – B interaction

Question 29.
If liquid A and B form ideal solution, then:
a) ∆Vmix is = 0
b) ∆Vmix = 0
c) ∆Gmix =0, ∆Smix = 0
d) ∆Smix = 0
Answer:
b) ∆Vmix = 0

Question 30.
Which liquid pair shows a positive deviation from Raoult’s law ?
a) Acetone – chloroform
b) Benzene – methanol
c) Water – nitric acid
d) Water – hydrochloric acid
Answer:
b) Benzene – methanol

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 31.
For A and B to form an ideal solution which of the following conditions should be satisfied ?
a) ∆Hmixing =0
b) ∆Vmixing =0
c) ∆Smixing =0
d) All three conditions mentioned above
Answer:
d) All three conditions mentioned above

Question 32.
Two liquids are mixed together to form a mixture which boils at same temperature, and their boiling point is higher than the boiling point of either of them so they shows.
a) no deviation from Raoult’s law
b) positive, deviation from Raoult’s law
c) negative-deviation from Raoult’s law
d) positive or negative deviation from Raoult’s law depending upon the composition
Answer:
c) negative-deviation from Raoult’s law

Question 33.
Molal elevation constant of liquid is:
a) the elevation in b.p. which would be produced by dissolving one mole of solute in 1oo g of solvent
b) the elevation of b.p. which would be produced by dissolving 1 mole solute in 10 g of solvent
c) elevation in b.p. which would be produced by dissolving 1 mole of solute in 1000g of solvent
d) none of the above
Answer:
c) elevation in b.p. which would be produced by dissolving 1 mole of solute in 1000g of solvent

Question 34.
The vapour pressure of pure liquid solvent is 0.50 atm. When a non – volatile solute B is added to the solvent, its vapour pressure drops to 0.30 atm. Thus, mole fraction of the component B is
a) 0.6
b) 0.25
c) 0.45
d) 0.75
Answer:
a) 0.6

Question 35.
The mass of a non – volatile solute (molecular mass = 40) which should be dissolved in 114 g octane to reduce its vapour pressure to 80 % will be
a) 20 g
b) 30 g
c) 10 g
d) 40 g
Answer:
c) 10 g

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 36.
The vapour pressure of pure liquid solvent A is 0.80 atm. When a non – volatile substance B is added to the solvent, its vapour pressure drops to 0.60 atm. Mole fraction of the component B in the solution is:
a) 0.50
b) 0.25
c) 0.75
d) 0.40
Answer:
b) 0.25

Question 37.
18 g of glucose (C6H12O6) is added to 178.2 g of water. The vapour pressure of water for this aqueous solution at 100°C is :
a) 752.40 torr
b) 759.00 torr
c) 7.60 torr
d) 76.00 torr
Answer:
a) 752.40 torr

Question 38.
Calculate the vapour pressure of a solution at 100°C containing 3 g of cane sugar in 33 g of water, (at wt. C = 12, H = 1, O = 16)
a) 760 mm
b) 756.90 mm
c) 758.30 mm
d) None of these
Answer:
b) 756.90 mm

Question 39.
Lowering of vapour pressure due to a solute in 1 molal aqueous solution at 100°C is
a) 13.44 mm Hg
b) 14.12 mm Hg
c) 31.2 mm Hg
d) 35.2 mm Hg
Answer:
a) 13.44 mm Hg

Question 40.
The vapour pressure of a dilute aqueous solution of glucose is 750 mm Hg at 373 K. The mole fraction of the solute is
a) \(\frac{1}{76}\)

b) \(\frac{1}{7.6}\)

c) \(\frac{1}{38}\)

d) \(\frac{1}{10}\)
Answer:
a) \(\frac{1}{76}\)

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 41.
When 3 g of a nonvolatile solute is dissolved in 50 g of water, the relative lowering of vapour pressure observed is 0.018 Nm-2. Molecular weight of the substance is
a) 60
b) 30
c) 40
d) 120
Answer:
a) 60

Question 42.
Elevation in boiling point of a molar (1M) glucose solution (d = 1.2 gmL-1) is
a) 1.34 Kb
b) 0.98 Kb
c) 2.40 Kb
d) Kb
Answer:
b) 0.98 Kb

Question 43.
Given, H2O (l) ⇌ H2O (g) at 373 K, ∆H° = 8.31 kcal mol-1. Thus, boiling point of 0.1 molal sucrose solution is
a) 373. 52 K
b) 373.052 K
c) 373.06 K
d) 374.52 K
Answer:
c) 373.06 K

Question 44.
A solution of 0.450 g of urea (mol. Wt. 60) in 22.5 g of water showed 0.170°C of elevation in boiling point. Calculate the molal elevation constant of water.
a) 0.17°C
b) 0.45°C
c) 0.51°C
d) 0.30°C
Answer:
c) 0.51°C

Question 45.
At higher altitudes, water boils at temperature < 100°C because
a) temperature of higher altitudes is low
b) atmospheric pressure is low
c) the proportion of heavy water increases
d) atmospheric pressure becomes more
Answer:
b) atmospheric pressure is low

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 46.
Which aqueous solution exhibits highest boiling point?
a) 0.015 M glucose
b) 0.01 M KNO3
c) 0.015 M urea
d) 0.01 M Na2SO4
Answer:
d) 0.01 M Na2SO4

Question 47.
A solution of urea in water has boiling point of 100.15°C. Calculate the freezing point of the same solution if Kf and Kb for water are 1.87 K kg mol-1 and 0.52 K kg mol-1 respectively
a) – 0.54°C
b) – 0.44°C
c) – 0.64°C
d) – 0.34°C
Answer:
a) – 0.54°C

Question 48.
Which will have largest ∆Tb?
a) 180 g glucose in 1 kg water
b) 342 g sucrose in 1,000 g water
c) 18 g glucose in 100 g water
d) 65 g urea in 1kg water
Answer:
d) 65 g urea in 1kg water

Question 49.
An aqueous solution of glucose boils at 100.01°C. The molal elevation constant for water is 0.5 K mol-1 kg. The number of molecules of glucose in the solution containing 100 g of water is
a) 6.023 × 1023
b) 12.046 × 1022
c) 12.046 × 1020
d) 12.046 × 1023
Answer:
c) 12.046 × 1020

Question 50.
The latent heat of vaporization of water is 9700 cal/mole and if the b.p. is 100°C, ebullioscopic constant of water is
a) 0.513°C
b) 1.026°C
c.) 10.26°C
d) 1.832°C
Answer:
a) 0.513°C

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 51.
If for a sucrose solution elevation in boiling point is 0.1 °C then what will be the boiling point of NaCl solution for same molal concentration
a) 0.1°
b) 0.2°C
c) 0.08°C
d) 0.01°C
Answer:
b) 0.2°C

Question 52.
The molal boiling point constant for water is 0.513°C kg mol-1. When 0.1 mole of sugar is dissolved in 200 ml of water, the solution boils under a pressure of one atmosphere at
a) 100.513°C
b) 100.0513°C
c) 100.256°C
d) 101.025°C
Answer:
c) 100.256°C

Question 53.
The boiling point of 0.1 m K4[Fe(CN)6] is expected to be (Kb for water = 0.52 K kg mol’1)
a) 100.52°C
b) 100.10°C
c) 100.26°C
d) 102.6°C
Answer:
c) 100.26°C

Question 54.
The value of Kf for the water is 1.86K Kg mole-1, calculated from glucose solution. The value of Kf for water calculated for NaCl solution will be :
a) = 1.86
b) < 1.86
c) > 1.86
d) zero
Answer:
a) = 1.86

Question 55.
The amount of urea to be dissolved in 500 cc of water (Kf = 1.86) to produce a depression of 0.186°C in the freezing point is :
a) 9 g
b) 6 g
c) 3 g
d) 0.3 g
Answer:
c) 3 g

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 56.
Freezing point of an aqueous solution is – 0.186°C. Elevation of boiling point of the same solution is if Kb = 0.512 K molality-1 and Kf= 1.86 K molality-1
a) 0.186°C
b) 0.0512°C
c) 0.092°C
d) 0.237°C
Answer:
b) 0.0512°C

Question 57.
What should be the freezing point of aqueous solution containing 17 g of C2H5OH in 1000 g of water (Kf for water = 1.86 deg kg mol-1)?
a) – 0.69°C
b) 0.34°C
c) 0.0°C
d) – 0.34°C
Answer:
a) – 0.69°C

Question 58.
The freezing point of equimolal aqueous solution will be highest for:
a) C6H5NH3Cl
b) Ca(NO3)2
c) La(NO3)2
d) C6H12O6
Answer:
d) C6H12O6

Question 59.
Cryoscopic constant of a liquid
a) is the decrease in freezing point when 1 g of solute is dissolved per kg of the solvent
b) is the decrease in the freezing point when 1 mole of solute is dissolved per kg of the solvent
c) is the elevation for 1 molar solution
d) is a factor used for calculation of depression in freezing point
Answer:
b) is the decrease in the freezing point when 1 mole of solute is dissolved per kg of the solvent

Question 60.
Which of the following solution will have highest freezing point?
a) 2 M NaCl solution
b) 1.5 M AlCl3 solution
c) 1 M Al2(SO4)3 solution
d) 3 M Urea solution
Answer:
d) 3 M Urea solution

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 61.
0.48 g of a substance is dissolved in 10.6 g of C6H6. The freezing point of benzene is lowered by 1.8°C. what will be the mol.wt. of the substance (Kf for benzene = 5)
a) 250.2
b) 90.8
c) 125.79
d) 102.5
Answer:
c) 125.79

Question 62.
Which of the following aqueous molal solution have highest freezing point?
a) Urea
b) Barium chloride
c) Potassium bromide
d) Aluminium sulphate
Answer:
a) Urea

Question 63.
What weight of NaCl is added to one liter of water so that ∆Tf/Kf = 1?
a) 5.85 g
b) 0.585 g
c) 0.0585 g
d) 0.0855 g
Answer:
c) 0.0585 g

Question 64.
A solution of glucose (C6H12O6) is isotonic With 4 g of urea (NH2 – CO – NH2) per liter of solution. The concentration of glucose is :
a) 4 g/L
b) 8 g/L
c) 12 g/L
d) 14 g/L
Answer:
c) 12 g/L

Question 65.
A 5% solution of cane sugar (molar mass = 342) is isotonic with 1% of a solution of unknown solute. The molar mass of unknown solute in g/mol is
a) 136.2
b) 171.2
c) 68.4
d) 34.2
Answer:
c) 68.4

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 66.
The weight of urea dissolved in 100 ml solution which produce an osmotic pressure of 20.4 atm, will be
a) 5 g
b) 4 g
c) 3 g
d) 6 g
Answer:
a) 5 g

Question 67.
In the phenomenon of osmosis, the membrane allow passage of _________.
a) Solute only
b) Solvent only
c) Both solute and solvent
d) None of these
Answer:
b) Solvent only

Question 68.
A 5.8% (wt./vol.) NaCl solution will exert an osmotic pressure closest to which one of the following:
a) 5.8% (wt./vol.) sucrose solution
b) 5.8% (wt./vol.) glucose solution
c) 2 molal sucrose solution
d) 1 molal glucose solution
Answer:
c) 2 molal sucrose solution

Question 69.
Osmotic pressure of a sugar solution at 24°C is 2.5 atmospheres. Determine the concentration of the solution in gram mole per liter.
a) 0.0821 moles/liter
b) 1.082 moles/liter
c) 0.1025 moles/liter
d) 0.0827moles/liter
Answer:
c) 0.1025 moles/liter

Question 70.
What is the freezing point of a solution that contains 10.0g of glucose C6H12O6 in 100 g of H2O? Kf = 1.86° C/m.
a) – 0.186°C
b) + 0.186°C
c) – 0.10°C
d) – 1.03°C
Answer:
d) – 1.03°C

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 71.
The order of osmotic pressure of equimolar solutions of BaCl2, NaCl and glucose will be:
a) BaCl2 > NaCl > glucose
b) NaCl > BaCl2 > glucose
c) glucose > BaCl2 > NaCl
d) glucose > NaCl > BaCl2
Answer:
a) BaCl2 > NaCl > glucose

Question 72.
The wt. of urea dissolved in 100 ml solution which produce an osmotic pressure of 20.4 atm, will be
a) 5 g
b) 4 g
c) 3 g
d) 6 g
Answer:
a) 5 g

Question 73.
A compound MX2 has observed and normal molar masses 65.6 and 164 respectively. Calculate the apparent degree of ionization of MX2:
a) 75%
b) 85%
c) 65%
d) 25%
Answer:
a) 75%

Question 74.
The freezing point of 0.2 molal K2SO4 is – 1.1°C. Calculate van’t Hoff facor and percentage degree of dissociation of K2SO4. Kf for water is 1.86°
a) 97.5
b) 90.75
c) 105.5
d) 85.75
Answer:
a) 97.5

Question 75.
For 0.1M solution, the colligative property will follow the order
a) NaCl > Na2SO4 > Na3PO4
b) NaCl > Na2SO4 ≈ Na3PO4
c) NaCl < Na2SO4 < Na3PO4
d) NaCl < Na2SO4 = Na3PO4
Answer:
c) NaCl < Na2SO4 < Na3PO4

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 76.
PH of a 0.1M monobasic acid is found to be 2. Hence its osmotic pressure at a given temp. T K is
a) 0.1 RT
b) 0.11 RT
c) 1.1 RT
d) 0.01 RT
Answer:
b) 0.11 RT

Question 77.
Which has the highest boiling point?
a) 0.1 m Na2SO4
b) 0.1 m Al(NO3)3
c) 0.1 m MgCl2
d) 0.1 m C6H12O6 (glucose)
Answer:
b) 0.1 m Al(NO3)3

Question 78.
Aluminium phosphate is 100% ionized in 0.01 molal aqueous solution. Hence ∆Tb/ Kb is:
a) 0.01
b) 0.015
c) 0.0175
d) 0.02
Answer:
d) 0.02

Question 79.
1.0 molal aqueous solution of an electrolyte X3Y2 is 25% ionized. The boiling point of the solution is (Kb for H2O = 0.52 K kg/mol)
a) 373.5 K
b) 374.04 K
c) 377.12 K
d) 373.25 K
Answer:
b) 374.04 K

Question 80.
The freezing point of 0,05 m solutions of a non – electrolyte in water is
a) -1.86 °C
b) -0.93°C
c)-0.093°C
d) 0.93°C
Answer:
c)-0.093°C

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 81.
For an ideal solution containing a non – volatile solute, which of the following expression is correctly represented?
a) ∆Tb = Kb × m
b) ∆Tb = Kb × M
c) ∆Tb = Kb × 2m
d) ∆Tb = Kb × 2M
Where m is the molality of the solution and Kb is molal elevation constant.
Answer:
a) ∆Tb = Kb × m

Question 82.
If 5.85 g of NaCl are dissolved in 90 g of water, the mole fraction of NaCl is
a) 0.1
b) 0.2
c) 0.3
d) 0.0196
Answer:
d) 0.0196

Question 83.
What will be the molarity of a solution containing 5g of sodium hydroxide in 250 ml solution?
a) 0.5
b) 1.0
c) 2.0
d) 0.1
Answer:
a) 0.5

Question 84.
If 5.85 g of NaCl (molecular weight 58.5) is dissolved in water and the solution is made up to 0.5 liter, the molarity of the solution will be
a) 0.2
b) 0.4
c) 1.0
d) 0.1
Answer:
a) 0.2

Question 85.
To prepare a solution of concentration of 0.03 g/ml of AgNO3, what amount of AgNO3 should be added in 60ml of solution
a) 1.8
b) 0.8
c) 0.18
d) None of these
Answer:
a) 1.8

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 86.
How many g of dibasic acid (mol.wt. 200) should be present in 100ml of its aqueous solution to give decinormal strength?
a) 1 g
b) 2 g
c) 10 g
d) 20 g
Answer:
a) 1 g

Question 87.
The molarity of a solution of Na2CO3 having 10.6 g/500 ml of solution is
a) 0.2 M
b) 2 M
c) 20 M
d) 0.02 M
Answer:
a) 0.2 M

Question 88.
Molecular weight of glucose is 180, A solution of glucose which contains 18 g per liter is
a) 2 molal
b) 1 molal
c) 0.1 molal
d) 18 molal
Answer:
c) 0.1 molal

Question 89.
0.5 M of H2SO4 is diluted from lliter to 10 liters, normality of resulting solution is
a) 1 N
b) 0.1 N
c) 10 N
d) 11 N
Answer:
b) 0.1 N

Question 90.
An aqueous solution of glucose is 10% in strength. The volume in which 1 g mole of it is dissolved will be
a) 18 liters
b) 9 liters
c) 0.9 liters
d) 1.8 liters
Answer:
d) 1.8 liters

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 91.
When 1.80 g glucose dissolved in 90 g of H2O, the mole fraction of glucose is
a) 0.00399
b) 0.00199
c) 0.0199
d) 0.998
Answer:
b) 0.00199

Question 92.
A 5 molar solution of H2SO4 is diluted from 1 liter to 10 liters. What is the normality of the solution?
a) 0.25 N
b) 1 N
c) 2N
d) 7 N
Answer:
b) 1 N

Question 93.
Normality of 2 M sulphuric acid is
a) 2 N
b) 4 N
c) N/2
d) N/4
Answer:
b) 4 N

Question 94.
What is the molarity of H2SO4 solution, that has a density 1.84 g/cc at 35°C and Contains solute 98% by weight
a) 4.18 M
b) 8.14 M
c) 18.4 M
d) 18 M
Answer:
c) 18.4 M

Question 95.
Which of the following is a colligative property?
a) Osmotic pressure
b) Boiling point
c) Vapour pressure
d) Freezing point
Answer:
a) Osmotic pressure

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 96.
The vapour pressure of benzene at a certain temperature is 640 mm of Eg. A non – volatile and non – electrolyte solid weighing 2.175 g is added to 39.08 g of benzene. The vapour pressure of the solution is 600 mm of Hg. What is the molecular weight of solid substance?
a) 49.50
b) 59.6
c) 69.5
d) 79.8
Answer:
c) 69.5

Question 97.
The average osmotic pressure of human blood is 7.8 bar at 37°C. What is the concentration of an aqueous NaCl solution that could be used in the Mood stream?
a) 0.16 mol/L
b) 0.32 mol/L
c) 0.60 mol/L
d) 0.45 mol/L
Answer:
b) 0.32 mol/L

Question 98.
The osmotic pressure in atmospheres of 10% solution of cane sugar at 69°C is
a) 724
b) 824
c) 8.21
d) 7.21
Answer:
c) 8.21

Question 99.
The molal boiling point constant for water is 0.513°C kg mol-1. When 0.1 mole of sugar is dissolved in 200 ml of water, the solution boils under a pressure of one atmosphere at
a) 100.513°C
b) 100.0513°C
c) 100.256°C
d) 101.025°C
Answer:
c) 100.256°C

Question 100.
The freezing point of a solution prepared from 1.25 g of a non – electrolyte and 20 g of water is 271.9 K. If molar depression constant is 1.8 K mole-1 then molar mass of the solute will be
a) 105.7
b) 106.7
c) 115.3
d) 93.9
Answer:
a) 105.7

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 101.
Osmotic pressure of 0.1 M solution of NaCl and Na2SO4 will be
a) same
b) osmotic pressure of NaCl solution will be more than Na2SO4 solution
c) osmotic pressure of Na2SO4 solution will be more than NaCl
d) osmotic pressure of NaSO4 will be less than that of NaCl solution
Answer:
c) osmotic pressure of Na2SO4 solution will be more than NaCl

Question 102.
At 25 °C the highest osmotic pressure is exhibited by 0.1 M solution of
a) CaCl2
b) KCl
c) Glucose
d) Urea
Answer:
a) CaCl2

Question 103.
Azeotropic mixture of HCl and water has
a) 84% HCl
b) 22.2% HCl
c) 63 % HCl
d) 20.2 HCl
Answer:
d) 20.2 HCl

Question 104.
The boiling point of water (100°C) becomes 100.25°C, if 3 grams of a nonvolatile solute is dissolved in 200 ml of water. The molecular weight of solute is (Kb for water is 0.6 K Kg mol-1)
a) 12.2 g mol-1
b) 15.4 g mol
c) 17.3 g mol-1
d) 20.4 g mol
Answer:
c) 17.3 g mol-1

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

II. Very short question and answer(2 Marks):

Question 1.
Define solution.
Answer:
A solution is homogeneous mixture of two or more substances, consisting of atom, ions or molecules. The constituent of the homogeneous mixture present in a lower amount is called the solute, and the one present in larger amount is called the solvent. For example, when a small amount of NaCl dissolved in water.

Question 2.
What is saturated solution?
Answer:
A saturated solution is one that contains the maximum amount of a solute that can dissolve in a solvent at a specific temperature.
For example, the solubility of NaCl in 100 g of water at 20°C is 36 g but at other temperatures, or in other solvents, is different.

Question 3.
What is unsaturated solution?
Answer:
An unsaturated solution is the one that contains less amount of solute than its capacity to dissolve.

Question 4.
What is Supersaturated solution?
Answer:
A super saturated solution is one that contains more dissolved solute than the saturated solution. It is generally not stable and eventually the dissolved solute will separate as crystals.

Question 5.
What is mass percentage?
Answer:
The mass percentage of a component in a solution is the mass of the component present in 100 g of the solution.
Mass percentage of component = \(\frac{\text { Mass of the component in the solution } \times 100}{\text { Total mass of the solution }}\)

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 6.
What is parts per million (ppm)?
Answer:
If the amount of solute in solution is very much less, then the concentration is expressed as parts per million (ppm).
Parts per million (ppm) = \(\frac{\text { Mass of the solute }(\mathrm{mg})}{\text { Mass of the solvent }} \times 10^{6}\)

Question 7.
What is Molarity?
Answer:
Molarity (symbol M) is defined as the number of moles of solute present in a liter of solution. The units of molarity are moles per liter (mol L-1) or moles per cubic decimeter (mol dm-3)
Molarity(m) = \(\frac{\text { Number of ntoles of solute }}{\text { Volume of solution in liter }}\)

Question 8.
What is Non – ideal solution?
Answer:
The solutions which do not obey Raoult’s law over the entire range of concentration, are called non – ideal solutions. For a non – ideal solution, there is a change in the volume and enthalpy upon mixing, i.e.
∆Hmixing ≠ 0 & ∆Vmixing ≠ 0.

Question 9.
State Raoult’s law.
Answer:
According to Raoult’s law, the vapor pressure of solvent over the solution is equal to the product of its vapor pressure in pure state and its mole fraction.
PA = P°A XA or
P = P°AXA

Question 10.
Define boiling point.
Answer:
The boiling point of a liquid is the temperature at which its vapour pressure becomes equal to the atmospheric pressure (1 atm).

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 11.
Define freezing point.
Answer:
Freezing point is defined as “the temperature at which the solid and the liquid states of the substance have the same vapour pressure”.

Question 12.
What is Osmotic pressure?
Answer:
Osmotic pressure can be defined as “the pressure that must be applied to the solution to stop the influx of the solvent (to stop osmosis) through the semi permeable membrane”.

Question 13.
State Dalton’s law.
Answer:
According to Dalton’s law of partial pressure the total pressure in a closed vessel will be equal to the sum of the partial pressures of the individual components.

Question 14.
What is elevation of boiling point? Give it.
Answer:
The temperature difference between the solution and pure solvent is called elevation of boiling point,
∆Tb = T – T°
Unit of ∆Tb is K Kg mole-1.

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

III. Short Question and answers(3 Marks):

Question 1.
What is mole fraction?
Answer:
Mole fraction, x, of solute is defined as the ratio of the number of moles of the components divided by the total number of the moles of all the component present in the solution.
Mole fraction of the solute xsolvent = \(\frac{\text { Moles of the component }}{\text { total number of moles of all the component in solution }}\)

Question 2.
What is volume percentage?
Answer:
It is defined as the volume of the component present in 100mL of the solution. If Va is a volume of solute and Vb is volume of solvent, then
Vollume percentage of solute = \(\frac{V_{a} \times 100}{V_{a}+V_{b}}\)

Question 3.
What are the advantages of using standard solution?
Answer:

  1. The error due to weighing the solute can be minimized by using concentrated stock solution that requires large quantity of solute.
  2. We can prepare working standards of different concentrations by diluting the stock solution, which is more efficient since consistency is maintained.
  3. Some of the concentrated solutions are more stable and are less likely to support microbial growth than working standards used in the experiments.

Question 4.
Limitations of Henry’s law.
Answer:
Henry’s law is applicable at moderate temperature and pressure only. Only the less soluble gases obeys Henry’s law. The gases reacting with the solvent do not obey Henry’s law.
Example:
Ammonia or HCl reacts with water and hence does not obey this law.
NH3 + H2O ⇌ NH4+ + OH

Question 5.
What is Van’t Hoff factor?
Answer:
It is defined as the ratio of the actual molar mass to the abnormal (calculated) molar mass of the solute. Here, the abnormal molar mass is the molar mass calculated using the experimentally determined colligative property.
i = \(\frac{\text { Normal (actual) molar mass }}{\text { obseved (abnormal) molar mass }}\)

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 6.
What is ideal solution?
Answer:
An ideal solution is a solution in which each component i.e. the solute as well as the solvent obeys the Raoult’s law over the entire range of concentration.
For an ideal solution,

  1. There is no change in the volume on mixing the two components (solute & solvents) (∆Vmixing =0).
  2. There is no exchange of heat when the solute is dissolved in solvent (∆Hmixing =0).
  3. escaping tendency of the solute and the solvent present in it should be same as in pure liquids.
    Example:
    benzene & toluene; h-hexane & n-heptane; ethyl bromide & ethyl iodide; chlorobenzene & bromobenzene.

Question 7.
What are colligative properties?
Answer:
“ The properties of the solutions which depend only on the number of solute particles but not on the nature of the solute are called colligative properties”. The following four colligative properties are very important.

  1. Relative lowering of vapor pressure (∆P)
  2. Elevation of boiling point (∆Tb)
  3. Depression of freezing point (∆Tb)
  4. Osmotic pressure (π)

Question 8.
What are the significances of Osmotic pressure?
Answer:
Unlike elevation of boiling point (for 1 molal solution the elevation in boiling point is 0.512°C for water) and the depression in freezing point (for 1 molal solution the depression in freezing point is 1.86°C for water), the magnitude of osmotic pressure is large.

The osmotic pressure can be measured at room temperature enables to determine the molecular mass of bio molecules which are unstable at higher temperatures. Even for a very dilute solution the osmotic pressure is large.

Question 9.
0.24 g of a gas dissolves in 1L of water at 1.5 atm pressure. Calculate the amount of dissolved gas when the pressure is raised to 6.0 atm at constant temperature?
Solution:
Psolute = KH Xsolute in solution
At pressure 1.5 atm,
P1 = KHX1 …………..(1)
At pressure 6.0 atm,
p2 = KHX2 …………….(2)
Dividing equation (1) by (2)
From equation = \(\frac{P_{1}}{P_{2}}=\frac{X_{1}}{X_{2}}\)

\(\frac{1.5}{6.0}=\frac{0.24}{x^{2}}\)

There fore
\(\frac{0.24 \times 6.0}{1.5}\) = 0.96 g/L

Question 10.
Why the carbonated drinks are stored in a pressurized container?
Answer:
The carbonated beverages contain carbon dioxide dissolved in them. To dissolve the carbon dioxide in these drinks, the CO2 gas is bubbled through them under high pressure. These containers are sealed to maintain the pressure. When we open these containers at atmospheric pressure, the pressure of the CO2 drops to the atmospheric level and hence bubbles of CO2 rapidly escape from the solution and show effervescence. The burst of bubbles is even more noticeable, if the soda bottle in warm condition.

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 11.
An aqueous solution of 2% non volatile solute exerts a pressure of 1.004 bar at the boiling point of the solvent. What is the molar mass of the solute when P°A is 1.013 bar?
Solution:
\(\frac{\Delta P}{P_{A}^{0}}=\frac{W_{B} \times M_{B}}{M_{B} \times W_{A}}\)

In a 2 % solution weight of the solute is 2 g and solvent is 98g
∆P = Psolution – P°A = 1.013 – 1.004 bar
= 0.009 bar
MB = \(\frac{\mathrm{P}_{\mathrm{A}}^{0} \times \mathrm{W}_{\mathrm{B}} \times \mathrm{M}_{\mathrm{A}}}{\Delta \mathrm{P} \times \mathrm{W}_{\mathrm{A}}}\)

MB = 2 × 18 × 1.013/(98 × 0.009) = 41.3 g mol-1

Question 12.
Ethylene glycol (C2H6O2) can be at used as an antifreeze in the radiator of a car. Calculate the temperature when ice will begin to separate from a mixture with 20 mass percent of glycol in water used in the car radiator. Kf for water = 1.86K Kg mol-1 and molar mass of ethylene glycol is 62 g mol-1.
Solution:
Weight of solute (W2) = 20 mass percent of solution means 20 g of ethylene glycol
Weight of solvent (water) W1 = 100 – 20 = 80 g
∆Tf = Kf m
= \(\frac{\mathrm{K}_{\mathrm{f}} \times \mathrm{W}_{2} \times 1000}{\mathrm{M}_{2} \times \mathrm{W}_{1}}=\frac{1.86 \times 20 \times 1000}{62 \times 80}\)
= 7.5 K
The temperature at which the ice will begin to separate is the freezing of water after the addition of solute i.e 7.5 K lower than the normal freezing point of water (273 – 7.5 K) = 265.5 K

Question 13.
At 400 K 1.5 g of an unknown substance is dissolved in solvent and the solution is made to 1.5 L. Its osmotic pressure is found to be 0.3 bar. Calculated the molar mass of the unknown substance.
Solution :
Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions 3

Question 14.
The depression in freezing point is 0.24 K obtained by dissolving 1 g NaCl in 200g water. Calculate van’t – Hoff factor. The molar depression constant in 1.86 K Kg mol-1
Solution :
Molar mass of solute = \(\frac{1000 \times K_{f} \times \text { mass of } N a C l}{\Delta T_{f} \times \text { mass of solvent }}\)

= \(\frac{1000 \times 1.86 \times 1}{0.24 \times 200}\)
= 38.75 g mol-1

Theoretical molar mass of NaCl is = 58.5 g mol-1

i = \(\frac{\text { Theoretical molar mass }}{\text { Experimental molar mass }}\)
= \(\frac{58.5}{38.75}\) = 1.50

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

IV. Long question and answers(5 Marks):

Question 1.
Explain the factors including the solubility of solute?
Answer:
Factors influencing the solute:
The solubility of a solute generally depends on the nature of the solute and the solvent in which it is dissolved. It also depends on the temperature and pressure of the solution.

Nature of solute and solvent:
Sodium-chloride, an ionic compound, dissolves readily iff a polar solvent such as water, but it does not dissolve in non polar-organic solvents such as benzene or toluene. Many organic compounds dissolve -readily in organic solvents and do not dissolve in water. Different gases dissolve in water to different extents: for example, ammonia is more soluble than oxygen in water.

Effect of temperature:

Solid solute in liquid solvent:
Generally, the solubility of a solid solute in a liquid solvent increases with increase in temperature. When the temperature is increased, the average kinetic energy of the molecules of the solute and the solvent increases. The increase in kinetic energy facilitates the solvent molecules to break the intermolecular attractive forces that keep the solute molecules together and hence the solubility increases.

When a solid is added to a solvent, it begins to dissolve. i.e. the solute leaves from the solid state (dissolution). After some time, some of the dissolved solute returns back to the solid state (recrystallisation). If there is excess of solid present, the rate of both these processes becomes equal at a particular stage. At this stage an equilibrium is established between the solid solute molecules and dissolved solute molecules.

Solute(solid) ⇌ Solute(dissolved)

According to Le-Chatelier principle, if the dissolution process is endothermic, the increase in temperature will shift the equilibrium towards left i.e solubility increases, for an exothermic reaction, the increase in temperature decreases the solubility. The solubilities, of ammonium nitrate, calcium Chloride, ceric sulphate nano-hydrate, and sodium chloride in water at different temperatures are given in the following graph.
Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions 4
Plot of solubility versus temperature for selective compounds

The following conclusions are drawn from the above graph:

1. The solubility of sodium chloride does not vary appreciably as the maximum solubility is achieved at normal temperature. In fact, there is only 10 % increase in solubility between 0° to 100 °C.
2. the dissolution process of ammonium nitrate is endothermic, the solubility increases steeply with increase in temperature.
3. In the case of ceric sulphate, the dissolution is exothermic and the solubility decreases with increase in temperature.
4. Even though the dissolution of calcium chloride is exothermic, the solubility increases moderately with increase in temperature. Here, the entropy factor also plays a significant role in deciding the position of the equilibrium.

Gaseous solute in liquid solvent:
In the case of gaseous solute in liquid solvent, the solubility decreases with increase in temperature. When a gaseous solute dissolves in a liquid solvent, its molecules interact with solvent molecules with weak intermolecular forces. When the temperature increases, the average kinetic energy of the molecules present in the solution also increases.

The increase in kinetic energy breaks the weak intermolecular forces between the gaseous solute and liquid solvent which results in the release of the dissolved gas molecules to the gaseous state. Moreover, the dissolution of most of the gases in liquid solvents is an exothermic process, and in such processes, the increase in temperature decreases the dissolution of gaseous molecules.

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 2.
Explain vapour pressure of liquid in liquids binary solution?
Answer:
Now, let us consider a binary liquid solution formed by dissolving a liquid solute ‘A’ in a pure solvent B in a closed vessel. Both the components A and B present in the solution would evaporate and an equilibrium will be established between the liquid and vapour phases of the components A and B.

The French chemist Raoult, proposed a quantitative relationship between the partial pressures and the mole fractions of two components A & B, which is known as Raoult’s Law. This law states that “in the case of a solution of volatile liquids, the partial vapour pressure of each component (A & B) of the solution is directly proportional to its mole fraction”.
According to Raoult’s law,
PA ∝ xA
PA = k xA
when xA = 1, k = P°A
where p°A is the vapour pressure of pure component A’ at the same temperature. Therefore,
PA = P°A xA
Similarly, for component ‘B’
PB =P°B xB
xA and xB are the mole fraction of the components A and B respectively.

According to Dalton’s law of partial pressure the total pressure in a closed vessel will be equal to the sum of the partial pressures of the individual components.
Hence,
Ptotal = PA + PB
Substituting the values of PA and PB from equations in the above equation,
Ptotal = XAA + XBB
We know that XA + XB = 1 or XA = 1 – XB
Therefore,
Ptotal = (1 – XB)P°A + XBB
Ptotal = P°A + XB(P°B – P°A)
The above equation is of the straight¬line equation form y = mx + c. The plot of Ptotalversus xB will give a straight line with (P°B – PA) as slope and P°A as the y intercept.

Let us consider the liquid solution containing toluene (solute) in benzene (solvent).

The variation of vapour pressure of pure benzene and toluene with its mole fraction is given in the graph.

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions 5
Solution of benzene in toluene obeying Raoult’s law

The vapour pressures of pure toluene and pure benzene are 22.3 and 74.7 mmHg, respectively. The above graph shows, the partial vapour pressure of the pure components increases linearly with the increase in the mole fraction of the respective components. The total pressure at any composition of the solute and solvent is given by the following straight line (represented as red line) equation.
PSolution = P°toluene + Xbenzene(Pbenzene – Ptoluene)

Question 3.
Explain Raoult’s law for the binary solution of Non-volatile solutes in liquids?
Answer:
When a nonvolatile salute js dissolved in a pure solvent, the vapour pressure of the pure solvent will decrease. In such solutions, the vapour pressure of the -Solution will depend only on the solvent ‘molecules as the solute is nonvolatile.

For example, when sodium chloride is added to the water, the vapor pressure of the salt solution is lowered. The vapour pressure of the solution is determined by the number of molecules of the solvent present in the surface at any time and is proportional to the mole fraction of the solvent.
Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions 6
Rate of vapourization reduced by presence of nonvolatile solute.

Psolution ∝ XA
Where XA is the mole fraction of the solvent
Psolution = kXA
When XA = 1, k = P°solvent
(P°solvent is the partial pressure of pure solvent)
PSolution = P°Solvent
\(\frac{P_{\text {solution }}}{P_{\text {solvent}}^{a}}\) = XA

1 – \(\frac{p_{\text {Solution }}}{p_{\text {Solvent }}^{0}}\) = 1 – XA

\(\frac{p_{\text {Solvent }}^{o}-p_{\text {Solurion }}}{P_{\text {Solvent }}^{0}}\) = XB
Where XB is the fraction of the solute
(∴ xA + xB = 1, XB = 1 – XA)

The above expression gives the relative lowering of vapour pressure. Based on this expression, Raoult’s Law can also be stated as “the relative lowering of vapour pressure of an ideal solution containing the nonvolatile solute is equal to the mole fraction of the solute at a given temperature”.

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 4.
What is ideal solution? Write special features and characters of ideal solution.
Answer:
An ideal solution is a solution in which each component i.e. the solute as well as the solvent obeys the Raoult’s law over the entire range of concentration. Practically no solution is ideal over the entire range of concentration. However, when the concentration of solute is very low, the dilute solution behaves ideally.

If the two components present in the solution (A and B) are identical in size, structure, and having almost similar intermolecular attractive forces between them (i.e. between A-A, B-B, and B-A) and then the solution tends to behave like an ideal solution.

For an ideal solution:
(i) there is no change in the volume on mixing the two components, (solute & solvents). (∆Vmixing = 0)
(ii) there is no exchange of heat when the solute is dissolved in solvent (∆Hmixing = 0).
(iii) escaping tendency of the solute arid the solvent present in it should be same as in pure liquids.
Example:
benzene & toulene; n-hexane & n-heptane; ethyl bromide & ethyl iodide; chlorobenzene & bromobenzene.

Question 5.
Explain Non – ideal solution with strong positive deviation.
Answer:
The solutions which do not Raoult’s law over the entire range, of concentration, are called non-ideal solutions. For a non-ideal solution, there is a change in the volume and enthalpy upon mixing, i.e.
∆Hmixing ≠ 0 &, ∆Vmixing ≠ 0. The deviation of the non-ideal solutions from the Raoult’s law can either be positive or negative.

Non-ideal solutions – positive deviation from Rauolt’s Law:
The nature of the deviation from the Rauolt’s law can be explained in terms ©f the intermolecular interactions between solute and solvent (B). Consider a case in which the intermolecular attractive forces between A and B are weaker than those between the molecules of A (A-A) and molecules of B (B-B).

The molecules present in such a solution have a greater tendency to escape from the solution when compared to the ideal solution formed by A and B, in which the intermolecular attractive forces (A-A, B-B, A-B) are almost similar. Consequently, the vapour pressure of such non-ideal solution increases and it is greater than the sum of the vapour pressure of A and B as predicted by the Raoult’s law. This type of deviation is called positive deviation.

Here, PA > p°A XA and pB > P°B XB
Hence Ptotal > p°A XA + PB XB

Let us understand the positive deviation by considering a solution of ethyl alcohol and water. In this solution the hydrogen bonding interaction between ethanol and water is weaker than those hydrogen bonding interactions amongst themselves (ethyl alcohol-ethyl alcohol and water-water interactions).

This results in the increased evaporation of both components from the aqueous solution of ethanol. Consequently, the vapour pressure of the solution is greater than the vapour pressure predicted by Raoults law. Here, the mixing process is endothermic i.e. ∆Hmixing > 0 and there will be slight increase in volume(∆Vmixing > 0).

Example:
Ethyl alcohol cyclohexane, Benzene & acetone, Carbon tetrachloride & chloroform, Acetone & ethyl alcohol, Ethyl alcohol & water.
Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions 7

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 6.
Explain Non – ideal solution with strong negative deviation.
Answer:
Let us consider a case where the attractive forces between solute (A) and solvent t (B) are stronger – thtSSar intermolecular attractive forces between the individual components (A – A & B – B). Here, the escaping tendency of A and B will be lower when compared with an ideal solution formed by A and B. Hence, the vapour pressure of such solutions will be lower than the sum of the vapour pressure of A and B. This type of deviation is called negative deviation. For the negative deviation,
PA < P°A XA and PB < P°B XB.

Let us consider a solution of phenol and aniline. Both phenol and aniline form hydrogen bonding interactions amongst themselves. However, when mixed with aniline, the phenol molecule forms hydrogen bonding interactions with aniline, which are stronger than the hydrogen bonds formed amongst themselves.

Formation of new hydrogen bonds considerably reduce the escaping tendency of phenol and aniline from the solution. As a result, the vapour pressure of the solution is less and there is a slight decrease in volume (∆Vmixing < 0) on mixing. During this process evolution of heat takes place i.e. ∆Hmixing < 0 (exothermic)

Example:
Acetone + chloroform, Chloroform + diethyl ether, Acetone + aniline, Chloroform + Benzene.

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions 8

Question 7.
Explain the factors responsible for deviation from Raoult’s law.
Answer:
Factors responsible for deviation from Raoult’s law:
The deviation of solution from ideal behavior is attributed to the following factors.

i) Solute-solvent interactions:
For an ideal solution, the interaction between the solvent molecules (A-A), the solute molecules (B-B) and between the solvent & solute molecules (A-B) are expected to be similar. If these interactions are dissimilar, then there will be a deviation from ideal behavior.

ii) Dissociation of solute:
When a solute present in a solution dissociates to give its constituent ions, the resultant ions interact strongly with the
solvent and cause deviation from Raoult’s law.
For example, a solution of potassium chloride in water deviates from ideal behavior because the solute dissociates to give K and Cl ion which form strong ion-dipole interaction with water molecules.
KCl(s) + H2O (l) → K+(aq)+ Cl(aq)

iii) Association of solute:
Association of solute molecules can also cause deviation from ideal behaviour. For example, in solution, acetic acid exists as a dimer by forming intermolecular hydrogen bonds, and hence deviates from Raoult’s law.

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions 9

iv) Temperature:
An increase in temperature of the solution increases the average kinetic energy of the molecules present in the solution which causes decrease in the attractive force between them. As result, the solution deviates from ideal behaviour.

v) Pressure:
At high pressure the molecules tend to stay close to each other and therefore there will be an increase in their intermolecular attraction. Thus, a solution deviates from Raoult’s law at high pressure.

vi) Concentration:
If a solution is sufficiently dilute there is no pronounced solvent-solute interaction because the number of solute molecules are very low compared to the solvent. When the concentration is increased by adding solute, the solvent-solute interaction becomes significant. This causes deviation from the Raoult’s law.

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 8.
How would you determine the molar mass of solute from Tb?
Answer:
The elevation of boiling point is directly proportional to the concentration of the solute particles.
∆Tb ∝ m
m is the concentration of solution expressed in molality.
∆Tb = Kbm
Where
Kb = molal boiling point elevation constant or Ebullioscopic constant.
∆Tb = \(\frac{K_{b} \times W_{B} \times 1000}{M_{B} \times W_{A}}\)

Mb = \(\frac{\mathrm{K}_{\mathrm{b}}}{\Delta \mathrm{Tb}} \times \frac{\mathrm{W}_{\mathrm{B}} \times 1000}{\mathrm{~W}_{\mathrm{A}}}\)

Question 9.
How would you determine the molar mass of solute from T?
Answer:
1f the solution is prepared by dissolving
WB g of solute in WB g of solvent, then the molality is,

m = \(\frac{\text { Number of moles of solute } \times 1000}{\text { weight of solvent in grams }}\)

Number of moles of solute = \(\frac{W_{B}}{M_{B}}\)
Where, MB = molar mass of the solute
Therefore,

m = \(\frac{\mathrm{W}_{\mathrm{B}} \times 1000}{\mathrm{M}_{\mathrm{B}} \times \mathrm{W}_{\mathrm{A}}}\)

∆Tf = \(\frac{K_{f} \times W_{B} \times 1000}{M_{B} \times W_{A}}\)

Molar mass can be calculated using

MB = \(\frac{\mathrm{Kb} \times \mathrm{W}_{\mathrm{B}} \times 1000}{\Delta \mathrm{T}_{\mathrm{b}} \times \mathrm{W}_{\mathrm{A}}}\)

Samacheer Kalvi 11th Chemistry Guide Chapter 9 Solutions

Question 10.
How would you determine the molar mass of solute form A?
Answer:
According to van’t Hoff equation π = cRT
c = \(\frac{n}{V}\)
Here, n = number of moles of solute dissolved in ‘V’ liter of the solution.
Therefore,
π = \(\frac{n}{V}\)RT
πV = nRT
If the solution is prepared by dissolving WBg of nonvolatile solute in WA g of solvent,
then the number of moles ‘n’ is,
n = \(\frac{\mathrm{W}_{\mathrm{B}}}{\mathrm{M}_{\mathrm{B}}}\)
since, MB = molar mass of the solute
Substituting the ‘n’ value, we get,
π = \(\frac{\mathrm{W}_{\mathrm{B}}}{\mathrm{V}} \frac{\mathrm{RT}}{\mathrm{M}_{\mathrm{B}}}\)

MB = \(\frac{W_{B}}{V} \frac{R T}{\pi}\)
From the above equation molar mass of the solute can be calculated.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Bio Zoology Guide Pdf Chapter 2 Kingdom Animalia Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

11th Bio Zoology Guide Kingdom Animalia Text Book Back Questions and Answers

Part I

I. Choose The Best Options

Question 1.
The symmetry exhibited in cnidarians is
a. Radial
b. Bilateral
c. Pentamerous radial
d. Asymmetrical
Answer:
a. Radial

Question 2.
Sea anemone belongs to phylum
a. Protozoa
b. Porifera
c. Coelenterata
d. Echinodermata
Answer:
c. Coelenterata

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 3.
The excretory cells that are found in platyhelminthes are
a. Protonephridia
b. Flame cells
c. Solenocytes
d. All of these
Answer:
b. Flame cells

Question 4.
In which of the following organisms, self fertilization is seen.
a. Fish
b. Round worm
c. Earthworm
d. Liver fluke
Answer:
d. Liver fluke

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 5.
Nephridia of Earthworms are performing the same functions as
a. Gills of prawn
b. Flame cells of Planaria
c. The trachea of insects
d. Nematoblasts of Hydra
Answer:
b. Flame cells of Planaria

Question 6.
Which of the following animals has a true coelom?
a. Ascaris
b. Pheretima
c. Sycon
d. Taenia solium
Answer:
b. Pheretima

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 7.
Metameric segmentation is the main feature of
a. Annelida
b. Echinodermata
c. Arthropoda
d. Coelenterata
Answer:
a. Annelida

Question 8.
In Pheretima locomotion occurs with the help of
a. circular muscles
b. longitudinal muscles and setae
c. circular, longitudinal muscles and setae
d. parapodia
Answer:
c. circular, longitudinal muscles and setae

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 9.
Which of the following have the highest number of species in nature?
a. Insects
b. Birds
c. Angiosperms
d. Fungi
Answer:
a. Insects

Question 10.
Which of the following is a crustacean?
a. Prawn
b. Snail
c. Sea anemone
d. Hydra
Answer:
a. Prawn

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 11.
The respiratory pigment in cockroach is
a. Haemoglobin
b. Haemocyanin
c. Heamoerythrin
d. None of the above
Answer:
d. None of the above

Question 12.
Exoskeleton of which phylum consists of chitinous cuticle?
a. Annelida
b. Porifera
c. Arthropoda
d. Echinodermata
Answer:
c. Arthropoda

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 13.
Lateral line sense organs occur in
a. Salamander
b. Frog
c. Water snake
d. Fish
Answer:
d. Fish

Question 14.
The limbless amphibian is
a. Icthyophis
b. Hyla
c. Rana
d. Salamander
Answer:
a. Icthyophis

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 15.
Four chambered heart is present in
a. Lizard
b. Snake
c. Scorpion
d. Crocodile
Answer:
d. Crocodile

Question 16.
Which of the following is not correctly paired?
a. Humans – Ureotelic
b. Birds – Uricotelic
c. Lizards – Uricotelic
d. Whale – Ammonotelic
Answer:
d. Whale – Ammonotelic

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 17.
Which of the following is an egg laying mammal?
a. Delphinus
b. Macropus
c. Ornithorhynchus
d. Equus
Answer:
c. Omithorhynchus

Question 18.
Pneumatic bones are seen in
a. Mammalia
b. Aves
c. Reptilia
d. Sponges
Answer:
b. Aves

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 19.
Match the following columns and select the correct option.

Column -IColumn – II
(p) Pila(i) Devil fish
(q) Dentalium(ii) Chiton
(r) Chaetopleura(iii) Apple snail
(s) Octopus(iv) Tusk shell

a. p – (ii), q – (i), r – (iii), s – (iv)
b. p – (iii), q – (iv), r – (ii), s – (i)
c. p – (ii), q – (iv), r – (i), s – (iii)
d. p – (i), q – (ii), r – (iii), s – (iv)
Answer:
b. p – (iii), q – (iv), r – (ii), s – (i)

Question 20.
In which of the following phyla, the adult shows radial symmetry but the larva shows bilateral symmetry?
a. Mollusca
b. Echinodermata
c. Arthropoda
d. Annelida
Answer:
b. Echinodermata

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 21.
Which of the following is correctly matched?
a. Physalia – Portuguese man of war
b. Pennatula – Sea fan
c. Adamsia – Sea pen
d. Gorgonia-Sea anemone
Answer:
a. Physalia – Portuguese man of war

Question 22.
Why are spongin and spicules important to a sponge?
Answer:
Spongin and spicules provide support and support the soft body parts of the sponges. The spicules give the sponges rigidity and form to the sponges.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 23.
What are the four characteristics common to most animals?
Answer:

  1. Cellular structure
  2. The nature of coelom ;
  3. Notochord
  4. Segmentation or absence of segmentation.

Question 24.
List the features that all vertebrates show at some point in their development.
Answer:
All vertebrates possess notochord during the embryonic stay. li is repLaced by vertebra) column. All vertebrates possess pained appendages such as fins or lunits. Skin is covered by a protective skeleton comprising of scales. fiathcrs hairs, claws, nails, etc. Respiration is aerobic through gills, skin. buccopharyngeal cavity’ and lungs. All vertebrates have a muscular heart with two, three, or four chambers and kidneys for excretion and osmoregulation.

Question 25.
Compare closed and opened circulatory system
Answer:

Open CirculationClosed Circulation
1. There is no blood vesselsPresence of blood vessels.
2. Blood remains filled in the tissue spaces.Blood is circulated through blood vessels
3. (Eg.) Arthropods, Mollusca, Echinodermata(Eg.) Earthworm, Cephalochordates, Chordates

Question 26.
Compare Schizocoelom with enterocoelom
Answer:

SchizocoelomateEnterocoelomate
1. Body cavity is formed by splitting of mesoderm.The body cavity is formed from the mesodermal pouches or archenteron.
2. (Eg.) Annelids, Arthropods(Eg.) Echinodermata Chordates

Question 27.
Identify the structure that the archenteron becomes in a developing animal.
Answer:
The archenteron becomes the cavity of the digestive tract.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 28.
Observe the animal below and answer the following questions
a. Identify the animal
b. What type of symmetry does this animal exhibit?
c. Is this animal Cephalized?
d. How many germ layers does this animal have?
e. How many openings does this animal’s digestive system have?
f. Does this animal have neurons?
Answer:
a) Sea anemone
b) Bilateral symmetry
c) It is not a cephalized animal
d) Diploblastic animal
e) One
f) Yes.
Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia 3

Question 29.
Choose the term that does not belong in the following group and explain why it does not belong?
Answer:

  • The notochord, cephalization, dorsal nerve cord, and radial symmetry.
  • Notochord, cephalization, and dorsal nerve cord are the characteristic features of chordates.
  • The radial symmetry is not a characteristic feature of chordate.
  • It is the feature of cnidarian and adult echinoderms. Hence it does not belong to the group.

Question 30.
Why flatworms are called acoelomates?
Answer:
The body cavity is formed from mesoderm but in flatworms, there is nobody cavity their body is solid with a perivisceral cavity.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 31.
What are flame cells?
Answer:
Flame cells are the specialized excretory cells in flatworms. They help in excretion and osmoregulation.

Question 32.
Concept Mapping – Use the following terms to create a concept map that shows the major characteristic features of the phylum Nematoda: Roundworms, pseudocoelomates, digestive tract, cuticle, parasite, sexual dimorphism
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia 2

Question 33.
In which phyla is the larva trochophore found?
Answer:
Trochopore larva is seen in the Phylum – Annelida.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 34.
Which of the chordate characteristics do tunicates retain as adults?
Answer:
Ventral and tabular heart. Respiration is through gill slits.

Question 35.
List the characteristic features that distinguish cartilaginous fishes from living jawless fishes.
Answer:

CyclostomataChondrichthyes
1. Some are ectoparasites on some fishes.They are free living.
2. Body is slender and eel-likeSkin is tough and covered with placoid scales
3. 6 to 15 pairs of gillslits for respiration.Respiration is by lamelliform gills.
4. Mouth is circular without jaws and suctorial.There are lower and upper jaws.
5. Migrate to freshwater for spawningThere is no migration during breeding.
6. After spawning they dieThey don’t die after spawning
7. OviparousOviparous, viviparous and Ova viviparous

Question 36.
List three features that characterise bony fishes.
Answer:

  1. These fishes have a bony endoskeleton.
  2. The skin is covered by ganoid, cycloid or ctenoid scales.
  3. Gills are covered by an operculum.
  4. They are ammonotelic.
  5. They have mesonephric kidneys.
  6. External fertilization is seen.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 37.
List the functions of air bladder in fishes.
Answer:

  • Air bladder may be connected to the gut or not.
  • They help in gaseous exchange.
  • In ray-finned fishes, they help in buoyancy.

Question 38.
Write the characteristics that contribute to the success of reptiles on land.
Answer:

  • The characteristics that contribute to the success of reptiles on land are as follows:
  • The presence of dry and cornified skin with epidermal scales or scutes prevents the loss of water.
  • The presence of metanephric kidney.
  • They are uricotelic (they excrete uric acid to prevent the loss of water).

Question 39.
List the unique features of a bird’s endoskeleton.
Answer:

  • The endoskeleton is fully ossified.
  • The long bones are hollow with air cavities. So that they can easily fly with lesser weight.

Question 40.
Could the number of eggs or young ones produced by an oviparous and viviparous female be equal? Why?
Answer:
No. The number of eggs or young ones produced by an oviparous and viviparous female cannot be equal. When the oviparous animals lay eggs in the external environment or in the medium, the chance of survival and successful development into the adults are not certain. But in the case of viviparous animals, young ones are nurtured by the adult animals. Hence, oviparous animals lay more eggs if they are fertilized in the medium or in water.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Part II

11th Bio Zoology Guide Kingdom Animalia Additional Important Questions and Answers

I. Choose The Best Options

Question 1.
…………………. is the first group of animals to exhibit tissue-level organization.
a. Cnidaria
b. Porifera
c. Mollusca
d. Echinodermata
Answer:
a. Cnidaria

Question 2.
Name the organs formed from ectoderm.
a. Heart
b. Hair
c. Muscle
d. Intestine
Answer:
b. Hair

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 3.
The mesoglea seen in between the ectoderm and endoderm is present in …………………. phylum.
a. Platyhelminthes
b. Arthropoda
c. Annelida
d. Coelenterates
Answer:
d. Coelenterates

Question 4.
Inporiferans through ………………. pores water enters into the body and goes out through.
a. Osculum Ostia
b. Ostia Osculum
c. Mouth Ostia
d. Mouth Osculum
Answer:
b. Ostia Osculum

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 5.
Choose the correct option.
a. Segmentation – Annelida
b. Archenteron – Heart Formation
c. Ostia – Sea anemone
d. Polyp Medusa – Phylum Ptenopora
Answer:
a. Segmentation – Annelida

Question 6.
Find out the correct and wrong statement and find out the correct sequence
I. In the phylum cnidaria on the tentacles nematocysts are present.
II. In evolutionary history the annelid is the first segmented animal.
III. The roundworms are diploblastic bilateral animals.
IV. The arthropods excrete through flame cells.
a. I – False, II – False, III – True, IV – True
b. I – True, II – False, III – False, IV – True
c. I – True, II – True, III – False, IV – Flase
d. I – False, II – True, III – True, IV – False
Answer:
c. I – True, II – True, III – False, IV – False

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 7.
The organism that shows the regeneration character
a. Planaria
b. Liver fluke
c. Tapeworm
d. Leech
Answer:
a. Planaria

Question 8.
What is the excretory organ of roundworm?
a. Flame cells
b. Rennet glands
c. Green glands
d. Malphigeal tubules
Answer:
b. Rennet glands

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 9.
The coelom of phylum Arthropoda is
a. Pseudo coelom
b. Eucoelom
c. Schizo coelom
d. Enter coelom
Answer:
c. Schizo coelom

Question 10.
Name the respiratory organ of Mollusca.
a. Ctenidia
b. Gills
c. Book lungs
d. Trachea
Answer:
a. Ctenidia

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 11.
Name the excretory organ of Cephalo Chordata.
a. Mesonephridia
b. Metanephridia
c. Protonephridia
d. Flame cells
Answer:
d. Flame cells

Question 12.
Name the organism which has both features of chordate and non-chordates?
a. Balanoglossus
b. Ascidia
c. Amphioxces
d. Salpa
Answer:
a. Balanoglossus

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 13.
…………………….. are called as tunicates
a. Urochordates
b. Cephalo chordates
c. Vertebrata
d. Hemi Chordata
Answer:
a. Urochordates

Question 14.
The eggs of birds are ………………..
a. Megalecithal
b. Mesolecithal
c. Telolocithal
d. Alecithal
Answer:
a. Megalecithal

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 15.
Find the correct answer by matching.
A. Sponges – I. Mesoglea
B. Open circulation – II. Asymmetrical
C. Diploblastic animal – III. Echinodermata
D. Snails – IV. Coanocytes
a. A – IV, B -I, C – II, D – III
b. A -I, B – II, C – III, D – IV
c. A – IV, B – III, C -I, D – II
d. A – IV, B – II, C – III, D -I
Answer:
C. Diploblastic animal – III. Echinodermata

Question 16.
Find out the correct pair.
a. Planula – Planeria
b. Regeneration – Annelida
c. Trochopore larva – Cnidaria
d. Veliger larva – Mollusca
Answer:
d. Veliger larva – Mollusca

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 17.
Which one of the following is not correctly paired?
a) Ctenophora – Veliger
b) Annelida – Trochophore
c) Cnidaria – Planula
d) Porifera – Parenchymula
Answer:
a) Ctenophora – Veliger

Question 18.
Find out the wrong statement.
a) In most animals the coelom lies between the body wall and the alimentary canal
b) In acoelomate organisms the free movement of the interval organ is restricted.
c) The cavity formed from the mesoderm is pseudo coelom.
d) If in a body cavity scattered pouches are seen then the coelom is pseudo coelom.
Answer:
c) The cavity formed from the mesoderm is pseudo coelom.

(2 marks)

II. Very Short Questions

Question 1.
What are pinococytes?
Answer:
In sponges, the outer surface is formed of plate-like cells that maintain the size and structure of the sponges are called pinococytes.

Question 2.
What are choanocytes?
Answer:
The inner layer of sponges is formed of flagellated collar cells called coanocytes. They maintain water flow through the sponges thus facilitating respiratory and digestive functions.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 3.
Define tissue.
Answer:
Cells that perform similar functions are aggregated to form tissues.

Question 4.
Define organ? Which was the first animal to have organ system?
Answer:

  • Different kinds of tissues aggregate to form an organ to perform a specific function.
  • In phylum Platyhelminthes, the organ level of organisation is first formed.

Question 5.
Differentiate between a complete digestive system from an incomplete digestive system.
Answer:

Incomplete Digestive SystemComplete Digestive System
1. There is a single opening in the digestive system which serves as both mouth and anus.
(Eg.) Platyhelminthes
1. There are separate openings for the mouth and anus. (Eg.) Chordates

Question 6.
What are diploblastic animals?
Answer:

  • Animals in which the cells are arranged in two embryonic layers the ectoderm and endoderm are diploblastic animals.
  • The ectoderm gives rise to the epidermis.
  • The endoderm gives rise to the tissue lining the gut.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 7.
What is radial symmetry?
Answer:
When any plane passing through the central axis of the body divides an organism into two identical parts, it is called radial symmetry, e.g. Cnidarian.

Question 8.
What is protostomia?
Answer:
In Eumetazoans, the embryonic blastopore that develops into the mouth are known as protostomia.

Question 9.
What are deutrostomia ?
Answer:
Eumetazoans in which the anus is formed from or near the blastopore and the mouth is formed away from the blastopore are deuterostomes.

Question 10.
List the excretory organs of phylum Arthropoda?
Answer:

  • Malphigean tubules
  • Green glands
  • Coxal glands

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 11.
Differentiate the respiratory pigment haemoglobin from haemocyanin.
Answer:

HaemoglobinHaemocyanin
1. It’s an iron-containing respiratory pigment.It’s a copper-containing respiratory pigment.
2. This is present in Annelida and ChordataThis is present in molluscan blood.

Question 12.
What are the advantages of bilaterally symmetrical animals?
Answer:
The bilaterally symmetrical animals can seek food, locate mates, escape from predators and move more efficiently. These animals have dorsal-ventral sides and anterior, posterior ends, right and left sides. They exhibit cephalization with sense organs and brain at the anterior end of the animal.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 13.
What is cleidoic egg?
Answer:
If the female organisms lay cleidoic eggs or shelled egg then it is known as cleidoic eggs.

Question 14.
What are the extraembryonic membranes present in reptiles?
Answer:

  1. Amnion
  2. Allantois
  3. Chorion
  4. Yolk sac

Question 15.
Name the muscles that help pigeons to fly. Write the kingdom, phyllum, and class for pigeon.
Answer:
a. Pectoralis major b. Pectoralis minor
(i) kingdom – Animalia
(ii) phylum – Chordata
(iii) class – Aves

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

( 3 marks)

III. Short Questions

Question 1.
What are the structures formed from ectoderm endoderm and mesoderm?
Answer:

  1. Edoderm – Skin, Hair, Nerves, Nail, Teeth
  2. Mesoderm – Muscles, Bones, Heart
  3. Endoderm – Intestine, Lungs, Liver.

Question 2.
Name the parts A, B, and C in the diagram?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia 5
A) Ectoderm
B) Pseudo coelom
c) Mesodorm

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 3.
Differentiate parazoa from eumetazoa?
Answer:

ParazoaEumetazoa
1.MulticellularMulticellular
2. Cells are looselyWell-developed tissues arranged. and organ system is present

Question 4.
Match
Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia 6
Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia 7
a) I – b, II – d, III – a, IV – c
b) I – a, II – b, III – d, IV – c
c) I – b, II – a, III – d, IV – c
Answer:
a) I – b, II – d, III – a, IV – c

Question 5.
Distinguish between hibernation and aestivation.
Answer:
Hibernation:

  • The dormancy period for animals during winter is called hibernation.
  • It is known as winter sleep.

Aestivation:

  • The dormancy period for animals during summer is called Aestivation.
  • It is known as summer sleep.

Question 6.
In the given diagram Balanoglossus mark A, B, and C.
Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia 8
Answer:
A) Proboscis
B) Collarette
c) Genital wings

Question 7.
Give any five characteristic features of Urochordata?
Answer:

  1. They are exclusively marine.
  2. They are mostly sessile some pelagic or free-swimming.
  3. The body is covered by a tunic.
  4. The coelom is absent.
  5. The notochord is present only in the tail region of the larval stage.
  6. The circulatory system is open type.

Question 8.
Look at the picture given below and answer questions.
a) What is the name of this fish?
b) What is the name of the larva of this fish?
c) What is the shape of the mouth?
Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia 9
Answer:
a) iprey
b) Ammocete
c) Circular

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 9.
What are the characteristic features of amphibia?
Answer:

  • Amphibians live both in aquatic as well as terrestrial habitats.
  • They are poikilothermic.
  • They have two pairs of limbs.
  • They may have a tail or may not be present.
  • Their skin is smooth or rough.
  • The heart is three-chambered.
  • They excrete urea as an excretory product.
  • The kidneys are mesonephric.
  • They are oviparous and development is indirect.

(5 Marks)

IV. Essay Questions

Question 1.
Explain various patterns of organisation in animals.
Answer:
Animals exhibit different patterns of organisation:
The cellular level of organisation:

  • Cells are loosely arranged without the formation of tissues.
  • There is a division of labour among the cells, e.g., sponges.

Tissue level of organisation:

  • Cells which perform a similar function are grouped into tissues.
  • The tissues perform a common function, e.g., cnidarians.

Organ level of organisation:
Different kinds of tissues aggregate to form an organ to perform a specific function e.g., flatworms and other hyper phyla.

Organ system level of organisation:

  • The tissues are organised to form organs and organ systems.
  • All the organ system function in a coordinated manner.

Question 2.
What is coelom? Describe its types?
Answer:
Body cavity lined with mesoderm is meant as a coelom. This lies between the body wall and the alimentary canal.

1.Pseudo coelom:
The body cavity is not lined by the mesodermal epithelium and the mesoderm is formed as scattered pouches between the ectoderm and endoderm. (Eg.) Roundworm

2.Eucoelom:
The coelom is a fluid-filled cavity that develops within the mesoderm and is lined by mesodermal epithelium called the peritoneum.

3.Schizocoelomates:
In these animals, the body cavity is formed by splitting mesoderm. (Eg.) Annelids.

4.Entero coelomate:
The body cavity is formed from the mesodermal pouches of the archenteron. (Eg.) Echinodermata

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 3.
Compare Platyhelminthes with Aschelminthes?
Answer:

PlatyhelminthesAschelminthes
1. The body is flattened oneThey are round in shape.
2. They are bilateral and triploblastic animal.They are bilateral and triploblastic animal.
3. AcoelomatePseudo coelom is present.
4. They have pseudo segmentationThe body is unsegmented
5. Excretion is through flame cells.Excretion is through rennet glands.
6. Sexes are not separate.
They are monoecious.
Sexes are separate and exhibit sexual dimorphism.
7. Some show regeneration capacity.No regeneration capacity.
8. Larva is present.No larva
9. (Eg.) Tape worm, Planeria(Eg.) Ascaris

Question 4.
Classify animals based on coelom.
Answer:
The cavity between the body wall and the gut wall is called coelom. If the animals do not have a coelom, they are called acoelomates. e.g., flatworms. In some animals, the body cavity is not fully lined by the mesodermal epithelium. The mesoderm is formed as scattered pouches between the ectoderm and endoderm. Such a body cavity is called a pseudocoel. The animals which have pseudocoel e.g. roundworms.

If the coelom develops within the mesoderm and is lined by mesodermal epithelium it is called eucoelom. The animals which have true coelom are called eucoelomates. If the body cavity is formed by splitting mesoderm, the animals are called schizocoelomates e.g., Annelids, arthropods, and mollusks. If the body cavity is formed from the mesodermal ‘ pouches of archenteron, the animals are called enterocoelomate animals, e.g., echinoderms, hemichordates, and chordates.

Question 5.
What are the characteristic features of Hemichordata?

  • They possess the characters of invertebrates and chordates.
  • This phylum consists of soft worm-like organisms.
  • They are triploblastic coelomate animals.
  • They are bilaterally symmetrical.
  • Their circulatory system is simple and open type.
  • They are ciliary feeders.
  • Respiration is through paired gill silts opening into the pharynx.
  • Excretion is through the glomerulus.
  • The nervous system is primitive sexes are separate.
  • In its development, there is a free-swimming to maria larva.

Question 6.
What are the general characters of the phylum Vertebrata?
Answer:

  1. They possess notochord during the embryonic stage only.
  2. The notochord is replaced by a cartilaginous or bony vertebral column in the adult.
  3. They possess paired appendages such as fins or limbs.
  4. Skin is covered by skeleton consists of scales, feathers, hairs, claws, nails.
  5. Respiration is through the gills skin buccopharyngeal cavity and lungs.
  6. The heart is with two or three or four chambers.
  7. Kidneys are for excretion and osmoregulation.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 7.
Write the general characters of the phylum cnidaria.
Answer:

  • The cnidaria is aquatic, radially symmetrical, and diploblastic.
  • The tentacles have stinging cells called cnidocytes or cnidoblasts or nematocysts.
  • They exhibit a tissue level of organisation.
  • They have a central gastrovascular cavity called coelenteron.
  • Digestion is both extracellular and intracellular.
  • Alternation of generation is seen in cnidarians which have polyp and medusa forms.
  • Development is indirect with planula larva e.g. Physalia.

Question 8.
What are the general characters of mammals?
Answer:

  • The body is covered by hairs.
  • They are found in a variety of habitats.
  • The presence of the mammary gland is the most unique feature of mammals.
  • They have two pairs of limbs.
  • The skin consists of sweat glands and sebaceous glands.
  • Exo skeleton includes horns spines, scales claws, etc.
  • Teeth are thecodont heterodont and diphyodont.
  • The heart is four-chambered and posses a left systematic arch.
  • Mammals have a large brain when compared to other animals.
  • Their kidneys are metanephric and are ureotelic.
  • All are homeothermic.

Question 9.
Give three distinct features of all chordates that are seen at some stage of their life cycle? What is the fate of two characters out of three in the matured adults?
Answer:

  1. Presence of notochord below the nerve chord and above the alimentary canal.
  2. The presence of the nerve cord lies above the notochord and below the dorsal body wall.
  3. Presence of pharyngeal gill slits in all chordates at some stage of their life cycle.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Features saw in the matured adult animals

LarvaAdult
NotochordIt may be partially or completely replaced by a backbone.
Nerve cordThey enlarged to form the brain and spinal cord.

Question 10.
Compare the chordates with non-chordates?
Answer:

ChordatesNon-chordates
1. Notochord is presentAbsence of notochord.
2. Dorsal hollow and single nerve cordDouble ventral solid nerve cord.
3. Pharynx perforated by gill slits.Gill slits absent.
4. Heart is ventrally placed.Heart indoors or laterally placed or absent.
5. A post-anal tail is presentPost anal tail is absent
6. Alimentary canal placed ventral to the nerve cordThe alimentary canal is placed dorsal to the nerve cord.

Question 11.
What are the parts of ABCD in the model diagram of Chordata?
Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia 10
Answer:
A) Dorsal Nerve Cord
B) Notochord
C) Mouth
D) Pharyngeal gill clefts
E) Muscle segment

Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Question 12.
Look into the given diagram and answer the question.
a) What is the name of the organism.
b) What is the respiratory organ of this animal.
c) What type of metamorphosis is seen?
d) Whether this organism contain nerve card?
e) What is the outer covering of it’s body?
Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia 11
Answer:
a) Ascidian
b) Gill clefts
c) Retrogressive metamorphosis
d) The larva consists of a nerve cord.
e) Tunic

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Bio Zoology Guide Pdf Chapter 1 The Living World Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

11th Bio Zoology Guide Living World Text Book Back Questions and Answers

Part I

Question 1.
A living organism is differentiated from a non-living structure based on
a. Reproduction
b. Growth
c. Metabolism
d. All the above
Answer:
d. All the above

Question 2.
A group of organisms having similar traits of a rank is
a. Species
b. Taxon
c. Genus
d. Family
Answer:
b. Taxon

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 3.
Every unit of classification regardless of its rank is
a. Taxon
b. Variety
c. Species
d. Strain
Answer:
a. Taxon

Question 4.
Which of the following is not present in the same rank?
a. Primata
b. Orthoptera
c. Diptera
d. Insecta
Answer:
a. Primata

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 5.
What taxonomic aid gives comprehensive information about a taxon?
a. Taxonomic Key
b. Herbarium
c. Flora
d. Monograph
Answer:
a. Taxonomic Key

Question 6.
Who coined the term biodiversity?
a. Walter Rosen
b. AG Tansley
c. Aristotle
d. AP de Candole
Answer:
a. Walter Rosen

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 7.
Cladogram considers the following characters
a. Physiological and Biochemical
b. Evolutionary and Phylogenetic
c. Taxonomic and systematic
d. None of the above
Answer:
b. Evolutionary and Phylogenetic

Question 8.
The molecular taxonomic tool consists of
a. DNA and RNA
b. Mitochondria and Endoplasmic reticulum
c. Cell wall and Membrane proteins
d. All the above
Answer:
a. DNA and RNA

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 10.
Differentiate between probiotics and pathogenic bacteria
Answer:

ProbioticsPathogenic bacteria
1. It converts the milk into curd (Eg.) LactobacillusIt causes diseases in plants and animals
2. It decomposes debris.Tomato – bacterial species
3. By the action of fermentation vinegar is produced. (Eg.) AcetobacterAnthrax, Tuberculosis Pneumonia Tetanus,

Question 11.
Why mule is sterile?
Answer:
Mule gets one set of chromosomes (32) from the male parent, horse and one set of chromosomes (31) from the female parent, donkey. These two sets of chromosomes do not match with each other and cannot produce gametes by meiosis. Hence mule is sterile in nature.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 12.
What is the role of Charles Darwin in relation to the concept of species?
Answer:
Charles Darwin’s book on Origin of Species explains the evolutionary connections of species by the process of natural selection.

Question 13.
Why elephants and other wild animals are entering the human living areas?

  • For the construction of houses, dams, and factories forests are destroyed. The area surface of forests is also getting reduced.
  • As the bull elephant is hunted for their tusks the cow elephant during breeding season enters in to the dwelling area of people.

Question 14.
What is the difference between a Zoo and a wildlife sanctuary?

ZooWildlife Sanctuary
1. They have formed artificially.It’s a place of nature.
2. Animals are in houses within the enclosure.Animals roam freely in their natural surrounding.
3. They are formed for the purpose of free time enjoyment of people.They are not formed for the purpose of enjoyment.

Question 15.
Can we use recent molecular tools to identify and classify organisms?
Answer:
The recent molecular taxonomical tools can be used to identify and classify the organism. The following molecular techniques and approaches are used in molecular tools.

  1. DNA barcoding – Short genetic marker in an organism’s DNA to identify whether it belongs to a particular species.
  2. DNA hybridization – Measures the degree of genetic similarity between pools of DNA sequences.
  3. DNA fingerprinting – to identify an individual from a sample of DNA by looking at unique patterns in their DNA.
  4. Restriction Fragment Length Polymorphism (RFLP) Analysis – the difference in homologous DNA sequences can be detected by the presence of fragments of different lengths after digestion of DNA samples.
  5. Polymerase chain reaction (PCR) sequencing- to amplify a specific gene or portion of the gene.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 16.
Explain the role of Latin and Greek names in Biology.
Answer:
Aristotle (384 to 322 BC) was the first to classify all animals in his Historia Animalium in Latin. He classified the living organisms into plants and animals. Animals were classified as walking (terrestrial), flying (birds), and swimming (aquatic) based on their locomotion.

He classified the animals with red blood cells as Enaima and those without red blood cells as Anima. Though his method of classification had limitations, his contribution to biology was remarkable. Theophrastus did his research on the classification of plants. He was known as the Father of Botany.

Part II 

11th Bio Zoology Guide The Living World Additional Important Questions and Answers

Question 1.
Biodiversity is
a. A species live in a particular ecosystem.
b. Presence of a large number of species in a particular ecosystem.
c. A species live in a different ecosystem.
d. Many species live in more than one ecosystem.
Answer:
b. Presence of a large number of species in a particular ecosystem.

Question 2.
Aristotle has classified organisms based on the following category of locomotion.
a. Walking & bore dwellers
b. Flying & arboreal
c. Swimmers & aquatic
d. All the above.
Answer:
c. Swimmers & aquatic
d. All the above.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 3.
Who is “Father of Botany”?
a. Theophrastus
b. John Ray
c. Carolus Linnaeus
d. Aristotle
Answer:
a. Theophrastus

Question 4.
Whose researchers confirm that species is a fundamental unit of classification.
a. John Ray
b. R.H. Whittaker
c. CarlWoese
d. Cavalier-Smith
Answer:
a. John Ray

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 5.
Find the correct pair.
1. Domestic Cat – Felis silvestris
2. Wildcat – Felis margarita
3. Wildcat – Felis Domestica
4. Tiger – Panthera tigers
Answer:
4. Tiger – Panthera tigers

Question 6.
Who has developed binomial nomenclature.
a. Carolous Linnaeus
b. Augustin
c. Aristotle
d. Ernst Haeckel
Answer:
a. Carolous Linnaeus

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 7.
Find the unrelated pair.
a. Carl Woese – Trinominal hypothesis
b. Cavalier-Smith – Seven kingdom system
c. Male Lion and female Tiger results in – Hinny
d. Male Tiger and female Lion results in – Tigon
Answer:
c. Male Lion and female Tiger results in – Hinny

Question 8.
The three domains classification is based on the difference in the gene.
a. 60s rRNA
b. 70s rRNA
c. l6s rRNA
d. m RNA
Answer:
c. l6s rRNA

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 9.
The prokaryotes that produce methane gas belongs to …………………… kingdom.
a. Monera
b. Eukarya
c. Bacteria
d. Archaea
Answer:
d. Archaea
Question 10.
Find out the correct sequence by matching.
A. Augustin Pyramus de Candole – Father of Botany
B. Aristotle – Father of Modern Taxonomy
C. Carolous Linnaeus – Father of Taxonomy
D. Theophrastus – Introduces Taxonomy
Answer:
D. Theophrastus – Introduces Taxonomy

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 11.
Crosses between animals – Match.
A. Male Horse + Female Donkey – Tigon
B. Male Donkey + Female Horse – Tiger
C. Male Lion + Female Tiger – Mule
D. Male Tiger + Female Lion – Hinny
a) A-II, B -1, C – IV, D – III
b) A-IV, B -1, C – II, D – III
c) A-I, B-II, C-III, D-IV
d) A-IV, B-I, C-II, D-III
Answer:
A-II, B -I, C – IV, D – III

Question 12.
Three domain classification was proposed by:
a. Cavalier-Smith
b. R.H. Whittaker
c. Carolus Linnaeus
d. Carl Woese
Answer:
d. Carlwoese

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 13.
Find out the wrong pair
a. Peacock – Pavocristatus
b. Tiger – Pantheratigeris
c. Man -Homosapiens
d. Domestic crow – Salcopopsindica
Answer:
d. Domestic crow – Salcopopsindica

Question 14.
Find the correct match.
1. John ray -a. Five kingdom concept
2. Linnaeus -b. Cladogram
3. Ernest Haeckel -c. Binomial nomenclature
4. R.H. Whittaker – d. Methodus Plantarum
a. 1 -d,2-c,3-b,4-a
b. 1-a,2-b,3-c,4-d
c. 1 – c, 2 – a, 3 – b, 4 – d
d. 1 – d, 2 – c, 3 – a, 4 – b
Answer:
a. 1 -d,2-c,3-b,4-a

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World
Question 15.
Where are the 80s and 70s ribosomes seen in Eukaryotic cells?
a. Cytoplasm – Chloroplast
b. Mitochondrial – Golgi apparatus
c. Chloroplast – Endo plasm reticulum
d. Nucleus – Lysosomes
Answer:
a. Cytoplasm – Chloroplast

( 2 marks)

II. Very Short Questions

Question 1.
Classification of organisms is necessary.
Answer:
Classification of organisms is necessary to recognize, identify them, and differentiate closely related species.

Question 2.
What are the unique characteristic features of living organisms?
Answer:

  • Cellular organization
  • Nutrition
  • Respiration
  • Metabolism
  • Movement
  • Reproduction
  • Excretion
  • Homeostasis

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 3.
The mating between different species produces sterile offsprings.
Answer:
The maternal and paternal chromosomes of the offsprings produced by the mating between different species are not identical and hence gametes are not produced by meiotic division.

Question 4.
What are the scientific stages of taxonomy?
Answer:

  • Characterization
  • Identification
  • Nomenclature
  • Classification

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 5.
Why are molecular tools used now to study taxonomy?
Answer:
Molecular tools are accurate and authentic. Hence they are used to study taxonomy.

Question 6.
What is phylogenetic or cladistics classification?
Answer:
It is a classification based on evolution and genetic relationship.

Question 7.
What is the phylogenetic tree?
Answer:
It’s a method of representing evolutionary relationships with the help of a tree diagram known as a cladogram.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 8.
What is a cladogram?
Answer:
Arranging organisms on the basis of their similar or derived characters produced a phylogenetic tree or cladogram.

Question 9.
What are the three domains of life indicate?
Answer:
This system emphasizes the separation of prokaryotes into two domains.

Question 10.
How Archaea differ from bacteria?
Answer:
If differs in cell wall composition and in membrane composition and rRNA type.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 11.
What is the seven taxonomic hierarchy?
Answer:

  1. Kingdom
  2. Phyla
  3. Class
  4. Order
  5. Family
  6. Genus
  7. Species

Question 12.
Define species?
Answer:
It is a group of animals having similar morphological features and is reproductively isolated to produce fertile offspring.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 13.
Define ‘Family’?
Answer:
It is a taxonomic category which includes a group of related genera with less similarity as compared to genus and species.

Question 14.
Define order?
Answer:
Order is an assemblage of one or more related families which show few common features. (Eg) Family Candiae and Felidae are placed in the order Carnivora.

Question 15.
Define class.
Answer:
Class includes one or more related orders with some common characters.

Question 16.
Define Phylum.
Answer:
The group of classes with similar distinctive characteristics constitute phylum.

Question 17.
Define animal kingdom.
Answer:
All living animals belonging to various phyla are included in the kingdom.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 18.
What are the features that we have to keep in mind in naming them scientifically?
Answer:

  • Morphology
  • Genetic information
  • Habitat
  • Feeding pattern
  • Adaptations
  • Evolutions

Question 19.
On whose guidelines naming animals in a scientific way is done?
Answer:
The naming of the organism is based on the guidelines of the international code of Zoological nomenclature.

Question 20.
What are taxonomical keys?
Answer:
Keys are based on a comparative analysis of the similarities and dissimilarities of organisms. There are separate keys for different taxonomic categories.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 21.
What is a museum?
Answer:
Biological museums have a collection of preserved plants and animals for study and ready reference.

Question 22.
Define Zoological parks.
Answer:
These are places where wild animals are kept in protected environments under human care.
It enables us to study their food habits and behaviour.

Question 23.
What are marine parks?
Answer:
Marine organisms are maintained in protected environments.

Question 24.
What are printed taxonomical tools?
Answer:

  • Identification cards
  • Description
  • Field guides
  • Manuals

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 25.
What is the phylogenetic tree?
Answer:
It is the inferred evolutionary relationships upon similarities and differences in their physical or genetic characters.

Question 26.
Define phylogeny.
Answer:
Relationships among various biological species based upon similarities and differences in their physical or genetic characteristics.

Question 27.
What are shared characters?
Answer:
A shared character is one that two lineages have in common.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 28.
What are derived characters?
Answer:
Derived character is one that evolved in the lineage leading up to a clade.

Question 29.
Vandaloor Zoological park.
Answer:

  • It is situated in the South-Western Part of Chennai.
  • It spreads over an area of 1500 acres.
  • It is one of the largest zoological parks in India.
  • The Zoo houses 2553 species of both flora and fauna.

( 3 marks)

III. Short Questions

Question 1.
Define ecosystem.
Answer:
The ecosystem is defined as a community of living organisms (plants and animals), non-living things (minerals, climate, soil, sunlight, and water), and their interrelationships, e.g. Forest and grassland.

Question 2.
On which criteria the systematic classification is done?
Answer:

  • Evolutionary history.
  • Environmental adaptations.
  • Environmental relationship.
  • The interrelationship between species.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 3.
Give an account of Aristotle’s classification?
Answer:

  •  In his book ‘History of Animals,’ he classifies plants and animals into two categories.
  • Based on locomotion walking, flying, swimming,
  • He classifies the organisms on the basis of blood.
  • He classifies the animals into two as ‘Enaima’ with blood and those without blood as’ Anaima’

Question 4.
Who has developed the five kingdom classification?
Answer:

  1. R.H. Whittaker proposed the five-kingdom classification.
  2. It is based on cell structure.
  3. Mode of nutrition.
  4. Mode of reproduction.
  5. Phylogenetic relationships.

The kingdoms are

  • Monera
  • Protista
  • Fungi
  • Plantae
  • Animalia

Question 5.
What are the special features of frogs that are identified in Western Gauts?
Answer:

  • This frog has shiny purple skin.
  • There is a light blue ring around the eyes.
  • It has a pointy big nose.
  • It’s Zoological name Nasikabatrachus Bhupathi.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 6.
What is trinomial nomenclature
Answer:
Giving three names to the species is meant as trinomial nomenclature.
When members of any species have large variations then a trinomial system is used.
The species is classified into subspecies and this is an extension of binominal nomenclature system which has an addition of subspecies. Followed by Genus name species subspecies name is also added.

Question 7.
What are the limitations of Aristotle’s classification?
Answer:
Many organisms were not fitting into his classification. Frogs have lungs and they are amphibians while their larva, the tadpole is aquatic and respires through gills. It is difficult to classify frogs according to his method. All flying organisms such as birds, bats, flying insects were grouped together. Ostrich, emu and a penguin are flightless birds and hence they cannot be classified by his method.

 (5 marks)

V. Essay Questions

Question 1.
List the defects of Aristotle’s classification.
Answer:

  • Aristotle’s classification system had limitations and many organisms were not fitting into his classification.
  • The tadpoles of frog are born in water and have gills but when they metamorphosed into adult frogs they have lungs and can live both in water and on land. There is no answer to this question.
  • Based on locomotion birds bats and flying insects were grouped either just by observing one single characteristic feature the flying ability.
  • On the contrary to the above-said example, the ostrich emu and penguin are all birds but cannot fly. He did not classify them as birds.

Question 2.
What is special about the Domain Archaea?
Answer:

  • This domain includes single-celled organisms the prokaryotes.
  • They have the ability to grow in extreme conditions like volcano vents hot springs and polar ice caps hence are called extremophiles.
  • They are capable of synthesizing their food without sunlight and oxygen by utilizing hydrogen sulphide and other chemicals from the volcanic vents.
  • Some of them produced methane.
  • Few live in salty environments and called Halophiles.
  • Some thrive in acidic environments and are called thormoacidophiles.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 3.
What is special about the domain bacteria?
Answer:

  1. Bacterias are prokaryotic.
  2. They do not have a definite nucleus and do not have histones.
  3. They have circular DNA.
  4. They do not possess membrane-bound organelles except for 70s ribosomes.
  5. Their cell wall contains peptidoglycans.
  6. Many are decomposers. Some are photo-synthesizers and few cause diseases.
  7. There are beneficial probiotic bacteria. (Eg.) Cyanobacteria produce oxygen.

Question 4.
What is the significance of cladistic classification?
Answer:
Cladistic classification takes into account ancestral characters (traits commons for the entire group) and derived characters (traits whose structure and function differ from the ancestral characters). The accumulation of derived characters resulted in the formation of new subspecies.

Question 5.
What are the basic roles to be followed in naming the animals?
Answer:

  • The scientific name should be italicized in printed form and if handwritten it should be underlined separately.
  • The generic name’s first alphabet should be in uppercase.
  • The specific name should be in lower case.
  • The scientific names of any two organisms are not similar.
  • The name of the scientist who first publishes the scientific name may be written after the species name along with the year of publication.
  • (Eg.) Lion – Felis Leo Linn . 1758 (or) Felis Leo L. 1758

Samacheer Kalvi 11th Bio Zoology Guide Chapter 1 The Living World

Question 6.
What are the rules to be followed in the nomenclature of organisms?
Answer:
The scientific name should be italicized in printed form and the generic name and specific name should be underlined separately if it is handwritten.

  • The first alphabet of the generic name should be of uppercase.
  • The specific name (species) should be in lower case letters.
  • The name or abbreviated name of the scientist who first published the scientific name may be written after the specific (species) name along with the year of publication, e.g. Felis Leo Linn., 1958.
  • If the specific (species) name is framed after any person’s name, the name of the species shall end with i, ii, or ae. e.g. Ground – dwelling lizard Cyrtodactylus varadgirii.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Bio Botany Guide Pdf Chapter 11 Transport in Plants Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Bio Botany Solutions Chapter 11 Transport in Plants

11th Bio Botany Guide Transport in Plants Text Book Back Questions and Answers

Part – I

Question 1.
In a fully turgid cell:
(a) DPD = 10 atm; OP = 5 atm; TP = 10 atm
(b) DPD = 0 atm; OP =10 atm; TP = 10 atm
(c) DPD = 0 atm; OP = 5 atm; TP = 10 atm
(d) DPD = 20 atm; OP = 20 atm; TP = 10 atm
Answer:
(b) DPD = 0 atm; OP =10 atm; TP = 10 atm

Question 2.
Which among the following is correct?
i) apoplast is fastest and operate in nonliving part
ii) Transmembrane route includes vacuole
in) Symplast interconnect the nearby cell through plasma desmata
iv) Symplast and the transmembrane route is in the living part of the cell
a) i and ii
b) ii and iii
c) iii and iv
d) i, ii, iii, iv
Answer:
d) i, ii, iii, iv

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 3.
What type of transpiration is possible in the xerophyte Opuntia?
(a) Stomatal
(b) Lenticular
(c) Cuticular
(d) All the above
Answer:
(b) Lenticular

Question 4.
Stomata of a plant open due to
a) Influx of K+
b) Effrilx of K+
c) Influx of Cl
d) Influx of OH
Answer:
a) Influx of K+

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 5.
Munch hypothesis is based on:
(a) translocation of food due to TP gradient and imbibition force
(b) ranslocation of food due to TP
(c) translocation of food due to imbibition force
(d) None of the above
Answer:
(b) ranslocation of food due to TP

Question 6.
If the concentration of salt in the soil is too high and the plants may wilt even if the field is thoroughy irrigated. Explain
Answer:
High salt concentration results in high be osmotic potential of the soil solution, so the plant has to use more energy to absorb water. Under extreme salinity conditions, plants may be unable to absorb water and will wilt even if the surrounding soil is thoroughly irrigated. This is also referred to as the osmotic or water deficit effect of salinity.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 7.
How phosphorylase enzyme open the stomata in starch sugar interconversion theory?
Answer:

  • The discovery of enzyme phosphorylase in guard cells by Hanes (1940) greatly supports the starch-sugar interconversion theory.
  • The enzyme phosphorylase hydrolyses starch into sugar and high PH followed and the opening takes place during the night.

Day:

1.Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 1
2. Photosynthesis occur
3. pH – increased
4. Movement of water from
5. subsidiary cells to guard cells
6. Guard cells become turgid
7. Opening of stomata

Night:

1. Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 2

2. No Photosynthesis
3. pH – lowered
4. Movement of water from guard cells
5. Guard cells become flaccid
6. Closure of stomata

Question 8.
List out the non-photosynthetic parts of a plant that need a supply of sucrose?
Answer:
The non-photosynthetic parts of a plant that need a supply of sucrose:

  1. Roots
  2. Tubers
  3. Developing fruits and
  4. Immature leaves.

Question 9.
What are the parameters which control water potential?
Answer:
1. Slatyer and Taylor (1960) introduced the concept of water potential.
Definition – water potential is the potential energy of water in a system – compared to pure water when temperature and pressure are kept constant.

2. It is also a measure of how freely water molecules can move in a particular environment or system. Water potential is denoted by the Greek symbol  Ψ (psi) and measured in Pascal (Pa). At standard temperature, the water potential of pure water is zero

3. Addition of solute to pure water decreases the kinetic energy thereby decreasing the water potential, from zero to negative.

4. So, Comparatively a solution always has low water potential than pure water. In a group of cells with different water potential, a water potential gradient is generated.

5. Water will move from higher water potential to lower water potential.
When potential ( Ψ) can be determined by. Solute concentration or Solute potential ( Ψs) Pressure potential ( Ψp)
By correlating two factors, water potential is written as (Ψws)+Ψp

a) Solute potential (Ψs) or Osmotic potential

  • Denotes the effect of dissolved solute on water potential.
  • In pure water, the addition of solute reduces its free energy and lowers the water potential value from zero to negative.
  • Thus the value of solute potential is always negative. In a solution at standard atmospheric pressure, water potential is always equal to solute potential (Ψw = Ψs ).

b) Pressure Potential (Ψp)

  • Pressure potential is a mechanical force working against the effect of solute potential.
  • Increased pressure potential will increase water potential and water enters cells and cells become turgid.
  • This positive hydrostatic pressure within the cell is called Turgor, pressure likewise, withdrawal of water from the cell decreases the water potential and the cell becomes flaccid.

Question 10.
An artificial cell made of selectively permeable membrane immersed in a beaker (in the figure) Read the values and answer the following questions?
Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 3
a) Draw an arrow to indicate the direction of water movement
b) Is the solution outside the cell isotonic, hypotonic or hypertonic?
c) Is the cell isotonic, hypotonic, or hypertonic?
d) Will the cell become more flaccid, more turgid or stay in original size?
e) With reference to artifical cell state, the process is endomosis or exomosis? Give reasons
Answer:
a)
Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 4
(b) Outside solution in hypotonic.
(c) The cell is hypertonic.
(d) The cell becomes more turgid.
(e) The process is endo – osmosis because the solvent (water) moves inside the cell.

Reason: Endomosis is defined as the osmotic entry of solvent into a cell when it is placed in pure water/Hypotonic solution. The solution in the beaker outside the cell is pure water. ( Ψw = 0), and water enters into the artificial cell which is placed inside the beaker of pure water, (i.e) from hypotonic to hypertonic solution.

Part II 

11th Bio Botany Guide Transport in Plants Additional Important Questions and Answers

I – Choose The Correct Answers

Question 1.
In plants, cell to cell transport is aided by:
(a) diffusion alone
(b) osmosis alone
(c) imbibition alone
(d) all the three above
Answer:
(d) all the three above

Question 2.
The smell from a lightened incense stick or mosquito coil or open perfume bottle in a closed room is due to
a) Osmosis
b) Facilitated diffusion
c) Simple diffusion
d) imbibition
Answer:
c. Simple diffusion

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 3.
Which of the following statements are correct?
(i) Cell membranes allow water and non-polar molecules to permeate by simple diffusion.
(ii) Polar molecules like amino acids can also diffuse through the membrane.
(iii) Smaller molecules diffuse faster than larger molecules.
(iv) Larger molecules diffuse faster than smaller molecules.

(a) (i) and (iv) only
(b) (i) and (iii) only
(c) (i) and (ii) only
(d) (ii) and (iv) only
Answer:
(b) (i) and (iii) only

Question 4.
Solute potential is also known as
a) Water potential
b) Pressure potential
c) Osmotic potential
d) Maic potential
Answer:
c. Osmotic potential

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 5.
The swelling of dry seeds is due to a phenomenon called:
(a) osmosis
(b) transpiration
(c) imbibition
(d) none of the above
Answer:
(c) imbibition

Question 6.
Cell A has an osmotic potential of -20 bars and a pressure potential of +6 bars. What will be its water potential?
a) -14 bars
b) +14 bars
c) -20 bars
d) +20 bars
Answer:
a. -14 bars

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 7.
The OP and TP of two pairs of cells A – B, and X-Y are under
a) Cell A: OP=-I0atm, TP=4atm
b) Cell B : OP = l0atm, TP = 6atm
c) Cell X: Op =-l0atm, TP = 4atm
d) CeIlY: OP = -Katm, TP = 4atm
The net movement of water shall be from
a) A toB and X to Y
b) A to B and Y toX
c) B to A and X to Y
d) B to A and Y to X
Answer:
d. B to A and Y to X

Question 8.
Water potential is influenced by which of the two factors among the given four
I) Concentration
II) Pressure
III) Temperature
IV) gravity
a) I & II
b) II & III
c) III & IV
d) I & IV
Answer:
a) I & II

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 9.
………………………. is equal to TP and is positive except plasmolysed cell and in xylem vessel where it is negative
a) Water potential
b) Pressure potential
c) Solute potential
d) Hydrostatic potential
Answer:
b. Pressure potential

Question 10.
Diffusion Pressure Deficit (DPD) was termed by Meyer in:
(a) 1928
(b) 1828
(c) 1936
(d) 1938
Answer:
(d) 1938

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 11.
Imbibants present in plants are generally
a) Hydrothermic
b) Hydrostatic
c) Hydrophilic
d) Hydrophobic
Answer:
c. Hydrophilic

Question 12.
Kramer (1949) recognised two distinct mechanisms, which independently operate in the absorption of water in plants are:
(a) osmosis and diffusion
(b) imbibition and diffusion
(c) diffusion and absorption
(d) active absorption and passive absorption
Answer:
(d) active absorption and passive absorption

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 13.
Root pressure is totally apsent in Gymnosperms because
a) Trachea absent
b) Tracheids absent
c) Trees are tall
d) Trees are comparatively short
Answer:
a. Trachea absent

Question 14.
When respiratory inhibitors like KCN, chloroform are applied:
(a) there is a decrease in the rate of respiration and an increase in the rate of absorption of water.
(b) there is an increase in the rate of respiration and a decrease in the rate of absorption of water.
(c) there is a decrease in the rate of respiration and also a decrease in the rate of absorption of water.
(d) there is an increase in the rate of respiration and also in the rate of absorption of water.
Answer:
(c) there is a decrease in the rate of respiration and also a decrease in the rate of absorption of water.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 15.
Find the DPD in a flaccid cell if its OP is 10
a) 20
b) 30
c) 10
d) 40
Answer:
c.10

Question 16.
Pulsation theory was proposed by:
(a) Strasburger
(b) Godsey
(c) J.C. Bose
(d) C.V. Raman
Answer:
(c) J.C. Bose

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 17.
When a cell is kept in 0.5m solution of sucrose it’s volume does not alter. If the same cell is placed in 0.5M solution of sodium chloride, the volume of the cell
a) Increase
b) Decrease
c) cell will be pIasrnoysed
d) Will does not show any change
Answer:
d. Will does not show any change

Question 18.
Indicate the correct statements:
(i) Root pressure is absent in gymnosperms.
(ii) Root pressure is totally absent in angiosperms.
(iii) There is a relationship between the ascent of sap and root pressure.
(iv) There is no relationship between the ascent of sap and root pressure.

(a) (i) and (ii)
(b) (ii) and (iii)
(c) (ii) and (iv)
(d) (i) and (iv)
Answer:
(d) (i) and (iv)

Match The Following & Find Out The Correct Order

Question 19.
I) Water potential – A) Turgor pressure
II) Solute potential – B) Osmotic potential + Pressure potential
III) Matric potential – C) Osmotic potential
IV) Pressure potential – D) Imbibition pressure
Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 5
Answer:
b) B C D A

Question 20.
I) Leaves – A) Antitransport
II) Seed – B) Transpiration
III) Roots – C) Negative osmotic potential
IV) Aspirin – D) Imbibition
V) Plasmolyced cell – E. Absorption
Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 6
Answer:
a) C B D E A

Question 21.
I) Transport of substance from a region of lower concentration to a region of higher concentration is with the expenditure of energy – A. Antiport
II) The movement of two types of molecules across the membrane in opposite direction – B. Symport The movement of a molecule across III) a membrane independent of other molecules – C. Active port
IV) The movement of two types of molecules across the membrane in the same direction – D. Uniport
Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 7
Answer:
c) C D A B

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 22.
I) Passive transport – A) Uphill transport
II) Active transport – B) Short distance transport
HI) Cell to cell transport – C) Long-distance transport
IV) Ascent of sap – D) Downhill transport
Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 8
Answer:
b) D A B C

Question 23.
The length and breadth of stomata is:
(a) about 10 – 30μ and 2 – 10μ respectively
(b) about 10 – 14μ and 3 – 10μ respectively
(c) about 10 – 40μ and 3 – 10μ respectively
(d) about 5 – 30μ and 5 – 10μ respectively
Answer:
(c) about 10 – 40μ and 3 – 10μ respectively

Question 24.
A membrane that permits the solvent and not the solute to pass through it is termed is
a) Permeable,
b) impermeable
c) semipermeable
d) differentially permeable
Answer:
c. Semi permeable

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 25.
Who did observe that stomata open in light and close in the night:
(a) Unger
(b) Sachs
(c) Boehm
(d) Von Mohl
Answer:
(d) Von Mohl

Question 26.
The phosphorylase enzyme in guard cells supports the starch-sugar interconversion theory. The above reaction is:
(a) oxidation reaction
(b) hydrolyses reaction
(c) reduction reaction
(d) none of the above
Answer:
(b) hydrolyses reaction

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 27.
If a cell kept in a solution of unknown concentration gets deplasmolysed the solution is
a) hypotonic
b) hypertonic
c) isotonic
d) detonic
Answer:
a. hypotonic

Question 28.
A cell placed in a strong salt solution will shrink because
a) the cytoplasm will decompose
b) mineral salts will break the cell wall
c) salt will leave the cell
d) water will leave by exosmosis
Answer:
d. water will leave by exosmosis

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 29.
Phenyl Mercuric Acetate (PMA), when applied as a foliar spray to plants:
(a) induces partial stomatal closure for two weeks.
(b) induces partial stomatal opening for two weeks.
(c) induces partial stomatal closure for four weeks.
(d) induces stomatal closure permanently
Answer:
(a) induces partial stomatal closure for two weeks.

Question 30.
The osmotic pressure of cell sap is maximum in
a) Hydrophytes
b) Halophytes
c) Xerophytes
d) Mesophytes
Answer:
b. Halophytes

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 31.
Say true or false and on that basis choose the right answer.
I) In facilitated diffusion, molecules move across the cell membrane with the help of special proteins, with the expenditure of energy
II) Porin is a larger transport protein, facilitates smaller molecules to pass through.
III) Aquaporins are recognized to transport urea, CO2, NH3 metalloid & ROS
IV) The carrier proteins structure does not get modified due to its association with the molecules
Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 9
Answer:
d. False True True False

Question 32.
I) Hypertonic is a strong solution (low solvent/high solute/ low Ψ )
II) Hypotonic is a weak solution (high solvent/low or zero solutes/ high Ψ)
III) Hypertonic is the weak solution (high solvent/low or zero solutes/high Ψ)
IV) Hypotonic is a strong solution (low solvent / high solute/low Ψ)
Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 10
Answer:
b. True True False False

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 33.
From sieve elements sucrose is translocated into sink organs such as root, tubers etc and this process is termed as:
(a) Xylem unloading
(b) Xylem uploading
(c) Phloem unloading
(d) Phloem uploading
Answer:
(c) Phloem unloading

Question 34.
The value of pure water is zero in which three aspects of the given options
I) Osmotic pressure
II) Osmotic potential
III) Water potential
IV) Pressure potential
a) I, II, & III
b) II, III & IV
c) I, Ill & IV
d) I, II & IV
Answer:
a. I, II & III

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 35.
Gases such as oxygen and carbon dioxide cross the cell membrane by
a) Passive diffusion through the lipid bilayer
b) Primary active transport
c) Specific gas transport proteins
d) Secondary active transport
Answer:

Question 36.
Hydathodes are generally present in plants that grow in:
(a) dry places
(b) moist and shady places
(c) sunny places
(d) deserts
Answer:
(b) moist and shady places

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 37.
Why sugars are transported in the form of su-crose in phloem?
a) It is inactive and highly soluble
b) It is active
c) It yields high ATP
d) It is lighter in weight.
Answer:
a. It is inactive and highly soluble

Question 38.
Unloading of pholem at sink includes
a) Passive transport
b) diffusio
c) Osmosis
d) Active transport
Answer:
d. Active transport

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 39.
The liquid coming out of the hydathode of grasses is:
(a) pure water
(b) not pure water
(c) a solution containing a number of dissolved substances
(d) saltwater
Answer:
(c) a solution containing a number of dissolved substances

Question 40.
In a flaccid cell
a) DPD = OP
b) DPD = TP
c) TP = OP
d) OP = O
Answer:
a. DPD = OP

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 41.
The pathway of water movement involving living part of a cell is
a) Apoplast pathway
b) symplast pathway
c) Transmembrane pathway
d) Lateral conduction
Answer:
b. Symplast pathway

Question 42.
The ascent of sap is
a) Upward movement of water in plants
b) downward movement of water in plants
c) upward and downward movement of water plants
d) None of the above
Answer:
a. upward movement of the water plants

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 43.
High tensile strength of water is due to
a) Adhesion only
b) cohesion only
c) Both (a) and (b)
d) None of these
Answer:
c. Both (a) and (b)

Question 44.
Maximum transpiration occur in
a) Mesophytes
b) Xerophytes
c) Hydrophytes
d) Epiphytes
Answer:
a. Mesophytes

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 45.
Supply ends in transport of solutes are
a) green leaves
b) root and stem
c) xylem and phloem
d) Hormones and enzymes
Answer:
c. Xylem and phloem

Question 46.
For guttation in plants, the process responsible is
a) Root pressure
b) Atmospheric pressure
c) Imbibition
d) None of these
Answer:
a. Root pressure

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 47.
Which of the following theories for Ascent of sap was proposed by famous Indian scientist. J.C. Bose.
a) Transpiration pull theory
b) Pulsation theory
c) Root pressure theory
d) Atmospheric pressure theory
Answer:
b. Pulsation theory

Question 48.
Which of the following plant material is an efficient water imbibant?
a) Lignin
b) Pectin
c) Cellulose
d) Agar
Answer:
d. Agar

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 49.
Which of the following helps in the Ascent of sap?
a) Root pressure
b) Transpiration
c) Capillarity
d) All the above
Answer:
d. All the above

Question 50.
In a girdled plant which of the following dies first?
a) Shoot
b) root
c) Both die simultaneously
d) None – the plant survives
Answer:
b. root

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 51.
Assertion:-A Imbibition is also diffusion
Reason -R The movement of water in the above process is along a concentration gradient.
a) Both A and Rare true and R is correct explanation of A
b) Both A and R are true but R is not the correct explanation of A
c) A true but R false
d) Both A and Rare false
Answer:
a) Both A and R are True and R is correct explanation of A

Question 52.
Assertion: – A In rooted plant, the transport of water and minerals in xylem is essentially multi-directional
Reason – R Organic compound and nuitrient undergoes undirectional transport only
Answer:
d) Both A and R are false

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 53.
Assertion: – A The adsorption of water by solid particles of an adsorbant with out forming a solution is known as imbibition
Reason: – R The liquid which is imbided is known as imbibate
Answer:
b) Both A and R are true but R is not the correct explanation of A

Question 54.
Assertion: – A In phloem loading, food is transported to the sink
Reason – R Food is transported from source to sink ‘
Answer:
d) Both Assertion ‘A’ and Reason ‘R’ are false

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 55.
Assertion – A: Xylem a principal water conducting ’
Reason -R: It has been recognised by girdling or ringing experiments
Answer:
a) Both A and R are True R is the correct explanation of A

Question 56.
Assertion: – A In phloem, sugar are translocated in non reducing form
Reason – R Non reducing sugars are most reactive sugars
Answer:
c) Assertion is true but Reason is false

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 57.
Assertion: AIn ringing experiment a narrow continuous band of tissues external to the phloem is removed
Reason: R Ringing experiment proves that phloem is involved in water transport ’
Answer:
d) Both A and R are false

II. Two Mark Questions

Question 1.
What is the need for the transport of materials in plants?
Answer:
Water absorbed from roots must travel up to leaves by xylem for food preparation by photosynthesis. Likewise, food prepared from leaves has to travel to all parts of the plant including roots.

Question 2.
What is osmosis
Answer:
It is a special type of diffusion almost same like simple diffusion but has a selectively permeable membrane is here, through which osmosis occur.
(OR)
It is the movement of water molecules from a place of its higher concentration, to the place of its lower concentration through a semipermeable membrane.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 3.
Define the term diffusion.
Answer:
The net movement of molecules from a region of their higher concentration to a region of their lower concentration along a concentration gradient until an equilibrium is attained.

Question 4.
The touch me plant closes its leaves at the touch – Explain.
Answer:

  • In the ‘Touch me not’ plant the touching act as stimulus, and it closes the leaves.
  • When we touch the plant, at that time the stem releases some chemicals, which force water to move out of the cell leading to the loss of Turgor pressure and the leaves droop down However after sometime they become normal.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 5.
What is meant by Porin?
Answer:
Porin is a large transporter protein found in the outer membrane of plastids, mitochondria and bacteria which facilitates smaller molecules to pass through the membrane.

Question 6.
Define water potential
Answer:

  • The potential energy of water in a system compared to pure water when both temperature and pressure are ketp same.
  • It is a measure of how freely water molecules can move in a given environment
  • Water potential of pure water is = 0

Question 7.
Define Diffusion Pressure Deficit.
Answer:

  • Termed by Meyer (1938)
  • The difference between the Diffusion pressure of the solution and its solvent at a particular temperature and atmospheric pressure of the solution and its solvent at a particular temperature and atmospheric pressure is called DPD.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 8.
Differentiate between short distance and Long Distance Transport.
Answer:

SDTLDT
1. Cell to cell Transport
Involve few cells ni lateral direction
Transport with in the network of xylem and
phloem
2. Connecting link to xylem bind phloem from root hairs to leaf tissuesDirect vertical – main Transport
3. Eg. Diffusion, Osmosis etc4. Eg. Ascent of sap & Translocation of solutes.

Question 9.
Differentiate between Passive & Active Transport
Answer:

PTAT
1. Down hill Transport (Phyical)Up hill Transport (Biological)
2. Occur According to concentration gradientOccur against concentration gradient
3. No expenditure of energyThere is expenditure of energy obtained from Respiration
4. Eg. Diffusion – Facilitated Diffusion osmosis etc.Eg. Na+ K+ ATP are pump.

Question 10.
Give two examples of the phenomenon of Imbibition.
Answer:
two examples for the phenomenon of Imbibition:

  1. The swelling of dry seeds.
  2. The swelling of wooden windows, tables, doors due to high humidity during the rainy season.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 11.
Explain carbonic Acid Exchange theory.
Answer:

  • Soil solution act as a medium of ion-exchange
  • The CO2 released by roots combine with water to form carbonic acid (H2CO3)
  • Carbonic acid dissociates into H+ + HCO3 in the soil solution.
  • H+ ions exchange with cations adsorbed on clay particles and cations from micelles get released int c.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 11

Question 12.
Give Answer in a sentence or two Distinguish between (i) Exomosis & Endomosis (ii) Apoplast & Symplast (iii) Cohesion & Adhesion (v) Influx & Efflux
Answer:

I) ExomosisEndomosis
The osmotic outflow of water, when cell placed in hypertonic solutionOsmotic inflow into the cell when placed in hypotonic solution or water
Eg. Preservation of Jam, Jellies, picklesEg. Swelling of Dry grapes placed in water
II) ApoplastSymplast
System of adjacent cell walls – continuous throughout except at the asparian strips of endodermis in the rootsSystem of interconnected protoplasts of neighbouring cells in plants
III) CohesionAdhesion
Attraction between molecules of a similar kindThe attraction between molecules of different kind
IV) InfluxEfflux
The entry of ion into the cell is known as InfluxThe exit of ion from the cell into outside is known as Efflux
It can be active or passiveIt can be active or passive.

Question 13.
What is meant by osmotic pressure?
Answer:
When a solution and its solvent (pure water) are separated by a semipermeable membrane, the pressure is developed in the solution, due to the presence of dissolved solutes. This is called osmotic pressure (OP).

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 14.
Define Root Pressure.
Answer:

  • Stephen Hales – coined the term
  • Stoking (1956) Defined the term.
  • A pressure developing in the tracheary elements of the xylem as a result of metabolic activities of the root.

Question 15.
Define the term osmosis.
Answer:
Osmosis (Latin: Osmos – impulse, urge) is a special type of diffusion. It represents the movement of water or solvent molecules through a selectively permeable membrane from the place of its higher concentration (high water potential) to the place of its lower concentration (low water potential).

Question 16.
Why plants transport sugars as sucrose and not as starch or Monosaccharide (Glucose & Fructose)
Answer:

NameTypeProperties
1.StarchPolysaccharide (non reducing sugar)Insoluble in water cann’t be transport
2. Glucose & FructoseMonosaccharides (reducing sugar)Soluble in water but less efficient in energy storage & reactive
3. SucroseDisaccharide(non reducing sugar)Soluble in water, even at high concentration, low viscosity, more efficient in energy storage no reducing ends make it inert than glucose & Fructose.

Question 17.
What are the three types of plasmolysis?
Answer:
Three types of plasmolysis occur in plants:

  1. Incipient plasmolysis
  2. Evident plasmolysis
  3. Final plasmolysis.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 18.
Identify the diagram and Neatly label the parts
Answer:
Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 12
The given diagram is the structure of Hydathode
A-Guard cell
B-Epithem
C-Tracheids

Question 19.
Identify the Diagram & Label the parts.
Answer:
Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 13
The given diagram explain Reverse osmosis
A – Pressure
B – Pure water
C – Saltwater
D – Membrane

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 20.
Differentiate between Ascent of sap and Translocation of solute.
Answer:

Ascent of sapTranslocation of solute
The upward transport of water along with dissolved minerals from roots to the aerial parts is called as Ascent of sap.The transport of food from the site of synthesis to the site of utilization or from source to sink is known as Translocation of organic solutes (a dissolved substance)
Occur through XylemOccur through Phloem

Question 21.
Give any two objections to starch-sugar interconversion theory.
Answer:
Two objections to starch – sugar interconversion theory:

  1. In monocots, the guard cell does not have starch.
  2. There is no evidence to show the presence of sugar at a time when starch disappears and stomata open.

Question 22.
Differentiate between cuticular and Lenticular Transpiration.
Answer:

Cuticular TranspirationLenticular Transpiration
Loss of water through cuticle is known as cuticular TranspirationSome pores
It is only about 5 to 10% of the total TranspirationPresent on the woody surface of stem (bark) are known as Lenticels
The thicker the cuticle, the lesser will be the Transpiration. Eg. xerophytesThe loss of water from the lenticel is Lenticular Transpiration – It is only about 0.1 % of the total.

Question 23.
Mention any two uses of anti – transpirants.
Answer:
Two uses of anti – transpirants:

  1. Anti – transpirants reduce the enormous loss of water by transpiration in crop plants.
  2. Useful for seedling transplantations in nurseries.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 24.
Give notes an Aquaporin.
Answer:

  • Water pore – Aquaporin in KBC was discovered by Peter Agre (Nobel Prize for chemistry – 2003)
  • Water channel protein is present in PM.
  • Regulate the massive amount of water transport across PM
  • 30 types of Aquaporins are known from maize

They also transporter

  • glycerol
  • urea
  • CO2
  • NH
  • metalloids & Reactive oxygen species (ROS)

Function:

  • They increase the permeability of the membrane of water
  • They confer drought and salt, stress tolerance.

Question 25.
Define the term Ion – Exchange.
Answer:
Ions of external soil solution are exchanged with the same charged (anion for anion or cation for cation) ions of the root cells.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 26.
A. Differentiate between Cohesion and Adhesion and
B. Add a note on their significance.
Answer:
A.

CohesionAdhesion
The strong mutual attraction between water molecules is called cohesion or cohesive force.The Attraction between a water molecule and the wall of the xylem element is called adhesion.

B. The cohesive and Adhesive forces work together to form an unbroken continuous water column in xylem.
The magnitude of cohesive force is much high (350 atm) and is more than enough to ascent sap in the tallest
trees.

III. 3 Mark Questions

Question 1.
Compare and Contrast Diffusion & Osmosis.
Answer:

DiffusionOsmosis
1. The net movement of molecules from a region of their higher concentration to a region of their lower concentration along a concentration gradient until an equilibrium is attainedIt is a special type of diffusion – There is movement of water or solvent molecules through a selectively permeable membrane from a place of its higher concentration to its lower concentration until an equilibrium is attained.
2. it is independent of the living systemIt is also independent of the living system
3. Passive processPassive process
4. Obvious in solids gases & liquids Only in liquid molecules Eg. diffusion of sugar in waterEg. Dry grapes, when kept in water swells, & becomes turgid.

Question 2.
Differentiate between osmotic pressure it and osmotic potential
Answer:

Osmotic pressureOsmotic potential
1. The hydrostatic pressure developed in a solution. due to the presence of dissolved solutes when it is separated from a pure solvent by a semi-permeable membrane.The ratio between the number of solvent particles and the number of solute particles in a solution or (lowering of free energy of water in a system due to the presence of solute particles
2. develops only in a confined system.develops in confined or an open system
3. The value is positive, though it is numerically equal to osmotic potentialThe value is negative though it is numerically opposite to osmotic pressure.

Question 3.
Do you have an R.O. Purifier ¡n your house? Explain the principle behind it.
Answer:

  • Yes / No – R.O. is working on the principle of osmosis. but in the reverse direction.
  • In regular osmosis water moves from its higher concentration to its lower concentration through the selectively permeable membrane but here water moves from lower concentration to higher concentration through selectively permeable membrane.
  • Since against concentration gradient, there is the expenditure of energy, to apply pressure, to force water in a reverse direction.
  • Eg- Desalination plants to purify seawater also work like R-O-Purifiers Movement of Water in house hold usage.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 14

Question 4.
Difference between various plasmolysis types
Answer:
Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 15

Question 5.
Define Antitranspirant.
Answer:
Antitranspirant is any material applied to plants to retard or reduce the rate of transpiration – without disturbing the process of gaseous exchange, for respiration and photosynthesis.
Eg. Colourless plastics silicone oil and low viscosity waxes.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 6.
What are the inducers of stomatal closure.
Answer:

  • Natural antitranspirants usually induce stomatal closure
    Eg. CO2 – inhibits photorespiration – thereby induces stomata! closure
  • Some chemicals, when applied as a foliar spray can induce stomatal closure for 2 – 3 weeks.
    Eg. (PMA) Phenyl Mercuric Acetate & (ABA) Abscisic Acid.

Question 7.
Fill in the blanks in the tabulations given below

The StudyYearScientist associated with it
1. The concept of water potential1960………………………………….
2. Active and Passive absorptions1949…………………………………
3. Pulsation theory1923…………………………………….

Answer:
1) Slatyer & Taylor 2) Kramer 3) J.C. Bose

Question 8.

Nature of membraneDefinitionExample
1. Impermeable1. ……………………………..suberized. cutinizedcell walls
2. ……………………………….Allow diffusion of solvent molecules, do not allow the passage of solute moleculesParched paper
3. Selectively permeablebiomembranes allow some solutes to pass in addition to solvent molecules3. ………………………………….

Answer:
1) Inhibit the movement of both solvent and solute molecules
2) Semipermeable
3) Tonoplast & plasmalemma

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 9.
Give the flow chart to cell to cell transport in plants.
Answer:
Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 16

Question 10.
Explain the capillary theory of Boehm (1809).
Answer:
Capillary theory: Boehm (1809) suggested that the xylem vessels work like a capillary tube. This capillarity of the vessels under normal atmospheric pressure is responsible for the ascent of sap. This theory was rejected because the magnitude of the capillary force can raise water level only up to a certain height. Further, the xylem vessels are broader than the tracheid which actually conducts more water and against the capillary theory.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 11.
Explain Phloem loading?
Answer:
Definition:
The products of Photosynthesis from the Mesophyll of leaves to sieve elements of phloem is known as phloem loading. (Just like the cement sack manufactured in a factory being loaded in a vehicle to be transported the respective site)
It involves 3 steps.
Step I:

  1. The chloroplast has photosynthate in the form of starch or Trlose phosphate
  2. It is transported to the cytoplasm, where it is converted into Sucrose.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 17

Question 12.
Explain the theory of photosynthesis in guard cells observed by Von Mohl with its demerits.
Answer:
Von Mohl (1856) observed that stomata open in light and close in the night. According to him, chloroplasts present in the guard cells photosynthesize in the presence of light resulting in the production of carbohydrate (Sugar) which increases osmotic pressure in guard cells. It leads to the entry of water from other cells and the stomatal aperture opens. The above process vice versa in the night leads to the closure of stomata.

Demerits:

  1. The chloroplast of guard cells is poorly developed and incapable of performing photosynthesis.
  2. The guard cells already possess much amount of stored sugars.

IV. 5 Mark Questions

Question 1.
Explain ‘routes’ of Water Absorption in the roots.
Answer:

  • Introduction
  • Root hair & other epidermal cells – By imbibition absorb water from soil –
  • By osmosis moves radically & centripetally – across
    • cortex
    • Endodermis
    • Pencycle & Xylem

There are 3 Routes

  • Apoplast
  • Symplast
  • Transmembrane route

I. Apoplast ( GK – Apo – Away) Everything external to PM
1. Cell walls
2. Extra Cellular Space
3. Interior of dead cells (vessel elements Tracheids)
Movement is continuous exclusively through the cell wall or nonliving part of the plant without crossing any membrane.

II. Symplast (GK – Sym = within)
Entire mass of cytosol of all the living cells in a plant + plasmo desmata + inter connecting cytoplasmic channel.
In the movement water has to cross PM, to enter cytoplasm of outer root cell; then move within adjoining
cytoplasm through plasmodesmata around the vacuoles without the necessity to cross more membrane it reaches xylem.

III. Trans – Membrane Route

  • Water enters a cell on one side and exits from the other side.
  • It crusses 2 membranes for each cell (also through to no plast).

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 18

Question 2.
Draw & Explain the structure of Stomata.
Answer:
1. Definition:
The epidermis of leaves and green stems possess many small pores called – Stomata

2. Length & Breadth
The length – 10- 40μ The Breadth – 3 – 10μ
Number Mature leaves contain 50- 500 stomata / mm2

3. Structure
a. Guard Cells – A pair of Kidney shaped cells (semilunar) surrounded a small opening called stoma
b. Subsidiary Cells – Guard cells attached to surrounding epidermal cells known as subsidiary cells or accessory cells.

  • The inner wall of guard cell is thicker
  • The stoma open into an interior substomatal cavity.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 19

Question 3.
Explain osmosis by Potato osmoscope Experiment.
Answer:
Aim : To demonstrate osmosis by Potato osmoscope
Apparatus used: Potato tuber, beaker containing water, sugar solution and pin.

Definition:
Diffusion of water or solvent from the region of higher water potential to a region of lower water potential
is known as osmosis.

Procedure:
Take a peeled potato tuber and make a cavity inside with the help of a knife fill the cavity with concentrated sugar solution and mark the initial level.
Place this set up in a beaker containing pure water After 10 minutes observe the sugar solution level and record your observation.

Observation:
There is rise in the level of the solution. in the cavity of the tuber due to osmosis
Inference: Osmosis has occured, through the potato osmoscope
Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 20

Question 4.
Measure Transpiration with Ganong’s Photometer
Answer:
Aim: To measure the rate of Transpiration with Ganong’s Potometer
Apparatus needed: Ganong’s Potometer, a twig, beaker, water, split rubber cork, and vaseline.

Procedure:

  • Ganong’s Potometer is a horizontal graduated tube which is bent in opposite directions at the ends.
  • A reservoir is fixed to the horizontal tube hear the wider end Reservoir has stop cock to regulate water flow.
  • A twig is fixed to the wider arm through the split cork. The apparatus is filled with water with water from reservoir.
  • The apparatus is made air tight by applying vaseline.
  • The other bent end of the horizontal tube is dipped into a beaker containing coloured water.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 21

An air bubble is introduced into the graduated tube at the narrow end. Keep the apparatus in bright sunIght
and observe

Observation:
As the twig transpires, the air bubble move towards the twig.
This loss is compensated by water ohsorption from the beaker.

inference:
By the experiment we can study the rate of Transpiration and rate of transpiration is equal to the rate of water absorption.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 5.
Explain Mechanism of Translocation by Munch Mass flow Hypothesis
Answer:
Munch – Proposed it in 1930 Crafts – elaborated it in 1938
Definition: Organic substances (solute) move from a region of high osmotic pressure (mesophyll) to
region of low OP along TP gradient.

Example – Physical system :
Chamber ‘A’ & chamber ‘B’ made up of semi permeable membrane connected by a tube ‘T’
A – Contain highly concentrated sugar solution (hypertonic)
B – Contain dilute sugar solution (hypotonic)
A – draws water from the reservoir by Endosmosis – TP of chamber ‘A’ increased

  • Continuous entry of water in to A – TP increased
  • Flow of solute from chamber A to B thro TP gradient.
  • The movement continues till both Aand B attain isotonic condition (equilibrium)
    (However if new sugar solution added to A system will start to run again)
    Example (Biological system)
  • Chamber A (Source) – (Equivalent to) – Mesophyll cells of leaves (High concentration of soluble food)
  • Chamber B (Sink) – (Equivalent to) – Cells of stem & Roots (Consumption end)
  • TubeT – (Analogous to) – Sieve tube to phloem

Steps :
1. Xylem (Reservoir) – Movement of water (Endomosis) – Mesophyll cells (TP increase)
2. Mesophyll cells (High TP) Source – enmass movement of  organic solutes through Phloem by TP Gradient  – Cells of stem & Root (low TP) (Sink)
Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 22

Question 6.
Explain the theory of K+ transport – or Explain the mechanism of stomatal movement
Answer:
Introduction:
Levit (1974) – Proposed it
Raschke (1975) – Elaborated it
Steps:
Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 23

This process of exchange of ions is called Actie ion exchange ( consume ATP) or Energy

  • Increased K+ ions in the Guard cells – balanced by CP ions
  • Increase in solute concentration (Hypertonic) Decrease in water potential
  • Water enters into Guard cells from subsidiary cells
  • Wall pressure increase Turgor pressure, Turgid guard cells – fall apart & opens the stoma

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 18.2
Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 24

  • Exit of H+
  • Intake of K+
  • Exit of K+
  • Loss of H2O
  • Uptake of H2O+
  • Turgidity of Guard Cells
  • Accumulation of CO2 – Lowering of pH
  • Opening of Stoma.
  • Activation of ABA
  • Closure of Stoma.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants

Question 7.
Explain Cytochrome Pump Theory (or) Explain Carrier concept of Active Absorption, through cytochrome Pump theory.
Answer:
Lunde gardth & Burstom (1933)- Proposed the Cytochrome

Pump theory:

  • There is correlation between Respiration & Anion absorption.
  • when a plant is transferred from water to salt solution, the rate of respiration increases – known as Anion respiration – or salt respiration

The Assumptions of Cytochrome pump theory:

  • The mechanism of anion and cation absorption is different.
  • Anion – absorption – through cytochrome pump or chain by Active process
  • An oxygen gradient is responsible for oxidation at outer surface of the membrane and reduction at the inner surface.

Explanation:

  • On the inner surface, the enzyme dehydrogenase Produces protons (W) and electrons (e)

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 27

  • Anions are picked up by oxidized cytochrome oxidase and transferred to the other members of the chain.
  • Theory assumes the passive movement of cations (C+) along the electrical gradient created by the accumulation of anions (A) at the inner surface of the membrane.

Defects :

    • Cations also induce respiration
    • to fail to explain the selective uptake of ions
    • It explains absorption of anions only.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 25

Question 8.
Explain the opening and closing of stomata by a starch – sugar – Interconversion theory.
Answer:
i) Lloyd (1908)
According to him, turgidity of Guard cell is due to interconversion of starch → sugar

  • Day time:
    Guard cells have sugar → so turgid → opening of stomata
  • Nighttime:
    Guard cells have starch → so loose turgidity (become flaccid) → closure of stomata

ii) Sayre (1920)
According to him, the pH of Guard cell determine opening and closing of stomata

  • Day time: Guard cells have high pH →so turgid → opening of stomata
  • Nighttime: Guard cells have low pH → become flaccid → closure of stomata to be elaborate
  • Day time: Utilisation of CO2. in photosynthesis → Starch into sugar → high pH → high Turgor pressure→Opening of Stomata
  • Night Time: No photosynthesis, so the accumulation of CO2 → sugar to starch → low pH → decrease in TP → closure of stomata

iii) Hanes (1940)
According to Hanes – Enzyme phosphorylase is responsible for starch sugar conversion in the guard cells.

Samacheer Kalvi 11th Bio Botany Guide Chapter 11 Transport in Plants 27

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Chemistry Guide Pdf Chapter 8 Physical and Chemical Equilibrium Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Chemistry Solutions Chapter 8 Physical and Chemical Equilibrium

11th Chemistry Guide Physical and Chemical Equilibrium Text Book Back Questions and Answers

Textbook Evaluation:

I. Choose the best answer:

Question 1.
If Kb and Kf for a reversible reaction are 0.8 × 10-5 and 1.6 × 10-4 respectively, the value of the equilibrium constant is,
a) 20
b) 0.2 × 10-1
c) 0.05
d) None of these
Answer:
a) 20

Question 2.
At a given temperature and pressure, the equilibrium constant values for the equilibria
3A2 + B2 + 2Cr Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 1 2A3BC and
A3BC Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 2 \(\frac{3}{2}\) [A2] + \(\frac{1}{2}\) B2 +C
The relation between K1 and K2 is
a) K1 = \(\frac{1}{\sqrt{\mathrm{K}_{2}}}\)

b)K2 = \(\mathrm{K}_{1}^{-1 / 2}\)

C) K12 = 2K2

d) \(\frac{\mathrm{K}_{1}}{2}\) = K2
Answer:
b)K2 = \(\mathrm{K}_{1}^{-1 / 2}\)

Question 3.
The equilibrium constant for a reaction at room temperature is K1 and that at 700 K is K2 If K1 > K2, then
a) The forward reaction is exothermic
b) The forward reaction is endothermic
c) The reaction does not attain equilibrium
d) The reverse reaction is exothermic
Answer:
a) The forward reaction is exothermic

Question 4.
The formation of ammonia from N2(g) and H2(g) is a reversible reaction 2NO(g) + O2(g) Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 2 2NO2(g) + Heat What is the effect of increase of temperature on this equilibrium reaction
a) equilibrium is unaltered
b) formation of ammonia is favoured
c) equilibrium is shifted to the left
d) reaction rate does not change
Answer:
c) equilibrium is shifted to the left

Question 5.
Solubility of carbon dioxide gas in cold water can be increased by
a) increase in pressure
b) decrease in pressure
c) increase in volume
d) none of these
Answer:
a) increase in pressure

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 6.
Which one of the following is incorrect statement?
a) for a system at equilibrium, Q is always less than the equilibrium constant
b) equilibrium can be attained from either side of the reaction
c) the presence of catalyst affects both the forward reaction and reverse reaction to the same extent
d) Equilibrium constant varied with temperature
Answer:
a) for a system at equilibrium, Q is always less than the equilibrium constant

Question 7.
K1 and K2 are the equilibrium constants for the reactions respectively.
N2(g) + O2(g)Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 1 2NO(g)
2NO(g) + O2(g) Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 22NO2 (g)
What is the equilibrium constant for the reaction NO2(g) ⇌ 1/2 N2(g) + O2(g)
a) \(\frac{1}{\sqrt{\mathrm{K}_{1} \mathrm{~K}_{2}}}\)

b) \(\left(\mathrm{K}_{1}=\mathrm{K}_{2}\right)^{1 / 2}\)

c) \(\frac{1}{2 \mathrm{~K}_{1} \mathrm{~K}_{2}}\)

d) \(\left(\frac{1}{\mathrm{~K}_{1} \mathrm{~K}_{2}}\right)^{3 / 2}\)
Answer:
a) \(\frac{1}{\sqrt{\mathrm{K}_{1} \mathrm{~K}_{2}}}\)

Question 8.
In the equilibrium, 2A(g) ⇌ 2B(g) + C2(g) the equilibrium concentrations of A, B and C2 at 400K are 1 × 10-4M, 2.0 × 10-3 M, 1.5 × 10-4 M respectively. The value of Kc for the equilibrium at 400 K is
a) 0.06
b) 0.09
c) 0.62
d) 3 × 10-2
Answer:
a) 0.06

Question 9.
An equilibrium constant of 3.2 × 10-6 for a reaction means, the equilibrium is
a) largely towards forward direction
b) largely towards reverse direction
c) never established
d) none of these
Answer:
b) largely towards reverse direction

Question 10.
\(\frac{\mathrm{K}_{\mathrm{C}}}{\mathrm{K}_{\mathrm{P}}}\) for the reaction,
N2(g) + 3H2(g) ⇌ 2NH3 (g) is
a) \(\frac{1}{\mathrm{RT}}\)
b) \(\sqrt{\mathrm{RT}}\)
c) RT
d) (RT)2
Answer:
d) (RT)2

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 11.
For the reaction AB (g) ⇌ A(g) + B(g), at equilibrium, AB is 20 % dissociated at a total pressure of P, the equilibrium constant Kp is related to the total pressure by the expression
a) P = 24 Kp
b) P = 8 Kp
c) 24 P = Kp
d) none of these
Answer:
a) P = 24 Kp

Question 12.
In which of the following equilibrium, Kp and Kc are not equal?
a) 2N0(g) ⇌ N2(g) + O2(g)
b) SO2(g) + NO2 ⇌ SO3(g) + NO(g)
c) H2(g) + I2(g) ⇌ 2HI(g)
d) PCl5 ⇌ PCl3(g) + Cl2(g)
Answer:
b) SO2(g) + NO2 ⇌ SO3(g) + NO(g)

Question 13.
If x is the fraction of PCl5 dissociated at equilibrium in the reaction PCl5 ⇌ PCl3 + Cl2 then starting with 0.5 mole of PCl5, the total number of moles of reactants and products at equilibrium is
a) 0.5 – x
b) x + 0.5
c) 2x + 0.5
d) x + 1
Answer:
b) x + 0.5

Question 14.
The values of Kp1 and Kp2; for the reactions, X ⇌ Y + Z, A ⇌ 2B are in the ratio 9 : 1 if degree of dissociation of X and A be equal then total pressure at equilibrium P1, and P2 are in the ratio
a) 36 : 1
b) 1 : 1
c) 3 : 1
d) 1 : 9
Answer:
a) 36 : 1

Question 15.
In the reaction
Fe(OH)3(S) ⇌ Fe3+ (aq) + 3OH (aq),
if the concentration of OH ions is decreased by 1/4 times, then the equilibrium concentration of Fe3+ will
a) not changed
b) also decreased by 1/4 times
c) increase by 4 times
d) increase by 64 times
Answer:
d) increase by 64 times

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 16.
Consider the reaction where Kp = 0.5 at a particular temperature PCl5(g) ⇌ PCl3 (g) + Cl2 (g) if the three gases are mixed in a container so that the partial pressure of each gas is initially 1 atm, then which one of the following is true.
a) more PCl3 will be produced
b) more Cl2 will be produced
c) more PCl5 will be produced
d) none of these
Answer:
c) more PCl5 will be produced

Question 17.
Equimolar concentrations of H2 and I2 are heated to equilibrium in a 1 litre flask. What percentage of the initial concentration of H2 has reacted at equilibrium if rate constant for both forward and reverse reactions are equal
a) 33%
b) 66%
c) (33)2%
d) 16.5 %
Answer:
a) 33%

Question 18.
In a chemical equilibrium, the rate constant for the forward reaction is 2.5 × 10-2, and the equilibrium constant is 50. The rate constant for the reverse reaction is,
a) 11.5
b) 50
c) 2 × 102
d) 2 × 10-3
Answer:
b) 50

Question 19.
Which of the following is not a general characteristic of equilibrium involving physical process
a) Equilibrium is possible only in a closed system at a given temperature
b) The opposing processes occur at the same rate and there is a dynamic but stable condition
c) All the physical processes stop at equilibrium
d) All measurable properties of the system remains constant
Answer:
c) All the physical processes stop at equilibrium

Question 20.
For the formation of Two moles of SO3(g) from SO2 and O2, the equilibrium constant is K1. The equilibrium constant for the dissociation of one mole of SO3 into SO2 and O2 is
a) \(1 / \mathrm{K}_{1}\)
b) K12
c) \(\left(\frac{1}{\mathrm{~K}_{1}}\right)^{1 / 2}\)
d) \(\frac{\mathrm{K}_{1}}{2}\)
Answer:
c) \(\left(\frac{1}{\mathrm{~K}_{1}}\right)^{1 / 2}\)

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 21.
Match the equilibria with the corresponding conditions:
i) Liquid ⇌ Vapour
ii) Solid ⇌ Liquid
iii) Solid ⇌ Vapour
iv) Solute(s) ⇌ Solute (Solution)
1) Melting point
2) Saturated solution
3) Boiling point
4) Sublimation point
5) Unsaturated solution

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 3
Answer:
b) 3 1 4 2

Question 22.
Consider the following reversible reaction at equilibrium, A + B ⇌ C, If the concentration of the reactants A and B are doubled, then the equilibrium constant will
a) be doubled
b) become one fourth
c) be halved
d) remain the same
Answer:
d) remain the same

Question 23.
[Co(H2O)6]2+ (aq) (pink) + 4Cl (aq) ⇌ [CoCl4]2-(aq) (blue) + 6 H2O (l)
In the above reaction at equilibrium, the reaction mixture is blue in colour at room temperature. On cooling this mixture, it becomes pink in color. On the basis of this information, which one of the following is true?
a) ∆H > 0 for the forward reaction
b) ∆H = 0 for the reverse reaction
c) ∆H < 0 for the forward reaction
d) Sign of the ∆H cannot be predicted based on this information
Answer:
a) ∆H > 0 for the forward reaction

Question 24.
The equilibrium constants of the following reactions are:
N2 + 3H2 ⇌ 2NH3; K1
N2 + O2 ⇌ 2NO; K2
H2 + 1/2O2 ⇌ H2O; K3
The equilbrium constant (K) for the reaction ;
2NH3 + 5/2 O2 ⇌ 2NO + 3H2O, will be
a) K23 K3/K1

b) K1 K33/K2

c) K2K33/K1

d) K2K3/K1
Answer:
c) K2K33/K1

Question 25.
A 20 litre container at 400 K contains CO2 (g) at pressure 0.4 atm and an excess (neglect the volume of solid SrO). The volume of the container is now decreased by moving the movable piston fitted in the container. The maximum volume of the container, when the pressure of CO2 attains its maximum value will be: Given that: SrCO3(S) ≅ SrO + CO2 (g) [Kp = 1.6 atm]
a) 2 litre
b) 5 litre
c) 10 litre
d) 4 litre
Answer:
b) 5 litre

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

II. Write brief answer to the following questions:

Question 26.
If there is no change in concentration, why is the equilibrium state considered dynamic?
Answer:
Rate of forward reaction = Rate of backward reaction

Question 27.
For a given reaction at a particular temperature, the equilibrium constant has constant value. Is the value of Q also constant? Explain.
Answer:
Kc and Qc are constant at equilibrium, both are temperature dependent. When Kc is constant at given temperature, Qc also constant.

Question 28.
What is the relation between Kp and Kc? Given one example for which Kp is equal to Kc.
Answer:
Kp = Kc(RT)∆ng
H2(g) + I2(g) ≅ 2HI (g) ; ∆ng = 0 ;
Kp = Kc.

Question 29.
For a gaseous homogeneous reaction at equilibrium, number of moles of products are greater than the number of moles of reactants. Is Kc is larger or smaller than Kp.
Answer:
Kp >Kc
np > nR

Question 30.
When the numerical value of the reaction quotient (Q) is greater than the equilibrium constant, in which direction does the reaction proceed to reach equilibrium?
Answer:
Q > Kc
Reverse reaction is favoured.

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 31.
For the reaction, A2(g) + B2(g) ⇌ 2AB(g); ∆H is -ve.
the following molecular scenes represent differenr reaction mixture.(A-green, B-blue)

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 4

i) Calculate the equilibrium constant Kp and (Kc).
ii) For the reaction mixture represented by scene (x), (y) the reaction proceed in which directions?
iii) What is the effect of increase in pressure for the mixture at equilibrium.
Answer:
Kc = \(\frac{[\mathrm{AB}]^{2}}{\left[\mathrm{~A}_{2}\right]\left[\mathrm{B}_{2}\right]}\) ; A – green, B – blue
Given that ‘V’ is constant(closed system)
At equilbrium,
Kc = \(\frac{(-)}{\left(\frac{2}{V}\right)\left(\frac{2}{V}\right)}\) = \(\frac{16}{4}\) = 4
Kp = Kc(RT)∆n = 4 (RT)0 = 4
At stage ‘x’,
Q = \(\frac{\left(\frac{6}{\mathrm{~V}}\right)^{2}}{\left(\frac{2}{\mathrm{~V}}\right)\left(\frac{1}{\mathrm{~V}}\right)}=\frac{36}{2}\) = 18
Q > Kc i.e., reverse reaction is favoured.
At stage ‘y’,
Q = \(\frac{\left(\frac{3}{V}\right)^{2}}{\left(\frac{3}{V}\right)\left(\frac{3}{V}\right)}=\frac{9}{3 \times 3}\) = 1
Kc > Q i.e., forward reaction is favoured.

Question 32.
State Le – Chateller principle.
Answer:
“If a system at equilibrium is distributed, then the system shifts itself in a direction that nullifies the effect of that disturbance”.

Question 33.
Consider the following reactions,
a) H2(g) + I2(g) ⇌ 2HI(g)
b) CaCO3(s) ⇌ CaO (s) + CO2(g)
c) S(s) + 3 F2(g) ⇌ SF6(g)
In each of the above reactions find out whether you have to increase (or) decrease the volume to increase the yield of the product.
Answer:
a) H2(g) + I2(g) ⇌ 2HI(g)
In this reaction, there is no effect on changing the volume. ∆ng = 0

b) CaCO3(s) ⇌ CaO (s) + CO2(g)
In this reaction, increases in volume favours forward reaction.

c) S(s) + 3 F2(g) ⇌ SF6(g)
In this reaction, decreases in volume favours forward reaction.

Question 34.
State law of mass action.
Answer:
The law states that, “At any instant, the rate of a chemical reaction at a given temperature is directly proportional to the product of the active masses of the reactants at that instant”.
Rate ∝ [Reactant]x
Active mass = \(\left(\frac{\mathrm{n}}{\mathrm{V}}\right)\) mol dm-3 (or) mol L-1

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 35.
Explain how will you predict the direction of an equilibrium reaction.
Answer:
From the knowledge of equilibrium constant, it is possible to predict the di¬rection in which the net reaction is taking place for a given concentration or partial pressure of reactants and products.
Consider a general homogeneous reversible reaction,

xA + yB ⇌ lC + mD

For the above reaction under non-equilibrium conditions, reaction quotient ‘Q’ is defined as the ratio of the product of active masses of reaction products raised to the respective stiochiometric coefficients in the balanced chemical equation to that of the reactants.

Under non – equilibrium conditions, the reaction quotient Q can be calculated using the following expression.
Q = \(\frac{[\mathrm{C}]^{1}[\mathrm{D}]^{\mathrm{m}}}{[\mathrm{A}]^{\mathrm{x}}[\mathrm{B}]^{\mathrm{y}}}\)

As the reaction proceeds, there is a continuous change in the concentration of reactants and products and also the Q value until the reaction reaches equilibrium. At equilibrium, Q is equal to Kc at a particular temperature. Once the equilibrium is attained, there is no change in the Q value. By knowing the Q value, we can predict the direction of the reaction by comparing it with Kc.
If Q = Kc, the reaction is in equilibrium state.
If Q > Kc, the reaction will proceed in the reverse direction, i.e., formation of reactants.
If Q < Kc, the reaction will proceed in the forward direction i.e., formation of products.
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 5
Predicting the direction of a reaction

Question 36.
Derive a general expression for the equilibrium constant Kp and Kc for the reaction, 3H2(g) + N2(g) ⇌ 2NH3(g).
Answer:
Let us consider the formation of ammonia in which, ‘a’ moles nitrogen and h’ moles hydrogen gas are allowed to react in a container of volume V. Let ‘x’ moles of nitrogen react with 3 x moles of hydrogen to give 2x moles of ammonia.
3H2(g) + N2(g) ⇌ 2NH3(g)

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 6

Applying law of mass action,
K2 = \(\frac{\left[\mathrm{NH}_{3}\right]^{2}}{\left[\mathrm{~N}_{2}\right]\left[\mathrm{H}_{2}\right]^{3}}\)
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 7
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 8

Question 37.
Write the balanced chemical equation for an equilibrium reaction for which the equilibrium constant is given by expression.
Answer:
Kc = \(\frac{\left[\mathrm{NH}_{3}\right]^{4}\left[\mathrm{O}_{2}\right]^{7}}{\left.[\mathrm{NO}]^{4} \mid \mathrm{H}_{2} \mathrm{O}\right]^{6}}\)
Balanced equation is:
4NO + 6H2O ⇌ 4NH3 + 7O2

Question 38.
What is the effect of added Inert gas on the reaction at equilibrium?
Answer:
When an inert gas (i.e., a gas which does not react with any other species involved in equilibrium) is added to an equilibrium system at constant volume, the total number of moles of gases present in the container increases, that is, the total pressure of gases increases. The partial pressure of the reactants and the products are unchanged. Hence at constant volume, the addition of inert gas has no effect on the equilibrium.

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 39.
Derive the relation between Kp and Kc.
Answer:
Let us consider the general reaction in which all reactants and products are ideal gases.
xA + yB ⇌ lC + mD
The equilibrium constant, Kc is,
Kc = \(\frac{\left[\mathrm{Cl}^{l}[\mathrm{D}]^{\mathrm{m}}\right.}{[\mathrm{A}]^{\mathrm{x}}[\mathrm{B}]^{\mathrm{y}}}\) ……………..(1)

and Kp is,
Kp = \(\frac{p_{C}^{l} \times p_{D}^{m}}{p_{A}^{x} \times p_{B}^{y}}\) ………….(2)

The ideal gas equation is,
PV = nRT
P = \(\frac{n}{V}\) RT
since, Active mass = molar concentration = n/V
P = active mass × RT
Based on the above expression the partial pressure of the reactants and products can be expresssed as,
PXA = [A]x[RT]x
PYB = [A]y[RT]y
PlC = [A]l[RT]l
PmD = [A]m[RT]m
On substituting in Eqn.(2).,
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 9
By comparing equation (1) and (4),
we get
Kp∆ng =Kc (RT) …………..(5)
Where,
∆ng is the difference between the sum of number of moles of products and the sum of number of moles of reactants in the gas phase.
The following relations become immediately obvious.
when ∆ng = 0.
Kp = Kc (RT)0 = Kc
Example :
H2(g) + I2(g) ⇌ 2HI(g)
N2 + O2 ⇌ 2NO(g)
when ∆ng = +ve
Kp = Kc(RT)+ve
Kp > Kc
Example:
2NH3(g) ⇌ N2(g) + 3H2(g)
PCl5(g) ⇌ PCl3(g) + Cl2(g)
When ∆ng = -ve
Kp = Kc(RT)-ve
Kp < Kc
Example:
2H2(g) + O2(g) ⇌ 2H2O(g)
2SO2(g)+ O2(g) ⇌ 2SO3(g)

Question 40.
One mole of PCl5 is heated in one litre closed container. If 0.6 mole of chlorine is found at equilibrium, Calculate the value of equilibrium constant.
Solution:
Given that,
[PCl5]initial = \(\frac{1 \text { mole }}{1 \mathrm{dm}^{3}}\)
[Cl2]eq = 0.6 mole dm-3
PCl5 ⇌ PCl3 + Cl2
[PCl3]eq = 0.6 mole dm-3
[PCl5]eq = 0.4 mole dm-3
∴ Kc = \(\frac{\left[\mathrm{PCl}_{3}\right]\left[\mathrm{Cl}_{2}\right]}{\left[\mathrm{PCl}_{5}\right]}=\frac{0.6 \times 0.6}{0.4}\)
= 0.9 mole dm-3

Question 41.
For the reaction SrCO3 (s) ⇌ SrO(s) + CO2(g) the value of equilibrium constant Kp = 2.2 × 10-4 at 1002 K. Calculate Kc for the reaction.
Solution :
For the reaction,
SrCO3(s) ⇌ SrO(s) + CO2(g)
∆ng = 1 – 0 = 1
∴ Kp = Kc (RT)
2.2 × 10-4 = Kc (0.0821) (1002)
Kc = \(\frac{2.2 \times 10^{-4}}{0.0821 \times 1002}\) = 2.674 × 10-6

Question 42.
To study the decomposition of hydrogen iodide, a student fills an evacuated 3 litre flask with 0.3 mol of HI gas and allows the reaction to proceed at 500°C. At equilibrium he found the concentration of HI which is equal to 0.05 M. Calculate Kc and Kp.
Solution :
V = 3 L
[HI]initial = \(\frac{0.3 \mathrm{~mol}}{3 \mathrm{~L}}\) 0.1 M
[HI]eq = 0.05 M
2 HI(g) ⇌ H2(g) + I2(g)
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 10

Kc = \(\frac{\left[\mathrm{H}_{2}\right]\left[\mathrm{I}_{2}\right]}{[\mathrm{HI}]^{2}}=\frac{0.025 \times 0.025}{0.05 \times 0.05}\) = 0.25
Kp = Kc(RT)(∆ng)
∆ng = 2 – 2 = 0
Kp = 0.25(RT)0
Kp = 0.25.

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 43.
Oxidation of nitrogen monoxide was studied at 200 with initial pressures of 1 atm NO and 1 atm of O2. At equilibrium partial pressure of oxygen is found to be 0. 5 atm calculate Kp value.
Solution:
2 NO(g) + O2(g) ⇌ 2NO2(g)
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 11
Kp = \(\frac{\left(P_{N O_{2}}\right)^{2}}{\left(P_{N O}\right)^{2}\left(P_{O}\right)}\)

= \(\frac{0.96 \times 0.96}{0.04 \times 0.04 \times 0.52}\)
Kp = 1.017 × 103.

Question 44.
1 mol of CH4, 1 mole of CS2 and 2 mol of H2S are 2 mol of H2 are mixed in a 500 ml flask. The equilibrium constant for the reaction Kc = 4 x 10-2 mol2 lit-2. In which direction will the reaction proceed to reach equilibrium ?
Solution :
CH4(g) + 2 H2S (g) ⇌ CS2(g) + 4H2(g)
Kc = 4 x 10-2 mol2 lit-2
Volume = 500 ml = \(\frac{1}{2}\) L
[CH4]in = \(\frac{1 \mathrm{~mol}}{\frac{1}{2} L}\) = 2 mol L-1;

[CH2]in = \(\frac{1 \mathrm{~mol}}{\frac{1}{2} L}\) = 2 mol L-1
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 12

Question 45.
At particular temperature Kc = 4 × 10-2 for the reaction, H2S ⇌ 2H2(g) + S2(g). Calculate the Kc for each of the following reaction.
i) 2H2S(g) ⇌ 2H2 + S2(g)
ii) 3H2S(g) ⇌ 3H2(g) + 3/2 S2(g)
Solution :
Kc = 4 × 10-2 for the reaction,
H2S ⇌ 2H2(g) + S2(g)
Kc = \(\frac{\left[\mathrm{H}_{2}\right]\left[\mathrm{S}_{2}\right]^{1 / 2}}{\left[\mathrm{H}_{2} \mathrm{~S}\right]}\)

⇒ 4 × 10-2 = \(\frac{\left[\mathrm{H}_{2}\right]\left[\mathrm{S}_{2}\right]^{1 / 2}}{\left[\mathrm{H}_{2} \mathrm{~S}\right]}\)

(i) 2H2S(g) ⇌ 2H2 + S2(g)
For the reaction,
2H2S(g) ⇌ 2H2 + S2(g)
Kc = \(\frac{\left[\mathrm{H}_{2}\right]^{2}\left[\mathrm{~S}_{2}\right]}{\left[\mathrm{H}_{2} \mathrm{~S}\right]^{2}}\)
= (4 × 10-2)2 = 16 × 10-4

(ii) 3H2S(g) ⇌ 3H2(g) + 3/2 S2(g)
For the reaction,
3H2S(g) ⇌ 3H2(g) + 3/2 S2(g)
Kc = \(\frac{\left[\mathrm{H}_{2}\right]^{3}\left[\mathrm{~S}_{2}\right]^{3 / 2}}{\left[\mathrm{H}_{2} \mathrm{~S}\right]^{3}}\)
= (4 × 10-2)3 = 64 × 10-6

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 46.
28 g of Nitrogen and 6 g of hydrogen were mIed In a 1 litre closed container. At equIlibrium 17 g NH3 was produced. Calculate the weight of nitrogen, hydrogen at equilibrium.
Solution:
Given mN2 =28g;
mH2 = 6g;
V = 1 L.
(nN2)initial = \(\frac{28}{28}\) = 1

(nH2)initial = \(\frac{6}{2}\) = 3
N2(g) + 3 H2(g) ⇌ 2NH3(g)
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 13
[NH3] = \(\frac{17}{17}\) = 1 mol
Weight of N2 = (no. of moles of N2) × (molar mass of N2)
= 0.5 × 28 = 14g
Weight of H2 = (no. of moles of H2) × (molar mass of H2)
= 1.5 × 2 = 3g

Question 47.
The equilibrium for the dissociation of XY2 is given as,
2 XY2(g) ⇌ 2 XY(g) + Y2(g)
if the degree of dissociation x is so small compared to one. Show that 2 Kp = PX3 where P is the total pressure and Kp is the dissociation equilibrium constant of XY2.
Answer:
2 XY2(g) ⇌ 2 XY(g) + Y2(g)
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 14

Question 48.
A sealed container was filled with 0.3 mol H2(g), 0.4 mol I2(g) and 0.2 mol HI(g) at 800 K and total pressure 1.00 bar. Calculate the amounts of the components in the mixture at equilibrium given that K = 870 for the reaction, H2(g) + I2(g) ⇌ 2 HI (g).
Solution:
A2(g) + B2(g) ⇌ 2 AB (g)
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 15

Given that, Kp = 1;
\(\frac{4 x^{2}}{(1-x)^{2}}\) = 1
⇒ 4x2 = (1 – x)2 = 1
⇒ 4x2 = 1 + x2 – 2x
3x2 + 2x – 1 = 0
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 16
x = 0.33 – 1(not possible)
∴ [A2]eq = 1 – x = 1 – 0.33 = 0.67
[B2]eq = 1 – x = 1 – 0.33 = 0.67
[AB2]eq = 2x × 0.33 = 0.66

Question 49.
Deduce the Vant Hoff equation.
Answer:
This equation gives that quantitative temperature dependence of equilibrium constant (K). The relation between standard free energy change (∆G°) and equilibrium constant is
∆G° = – RT In K ………………..(1)
We know that, ∆G° = ∆H° – T∆S° …………(2)
Substituting (1) in equation (2)
– RT In K = ∆H° – T∆S°
Rearranging, In K = \(\frac{\Delta \mathrm{H}^{0}}{\mathrm{RT}}+\frac{\Delta \mathrm{S}^{0}}{\mathrm{RT}}\) ……………(3)
Differentiating equation (3) with respect to temperature,
\(\frac{\mathrm{d}(\ln \mathrm{K})}{\mathrm{dT}}=\frac{\Delta \mathrm{H}^{0}}{\mathrm{RT}^{2}}\) ……………….(4)
Equation (4) is known as differential form of van,t Hoff equation.
On integrating the equation (4), between T1 and T2 with their respective equilbrium consatnts K1 and K2.
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 17
Equation 5 is known as integrated form of Van’t Hoff equation.

Question 50.
The equilibrium constant Kp for the reaction N2(g) + 3H2(g) ⇌ 2NH3(g) is 8.19 × 102 at 298 K and 4.6 × 10-1 at 498 K. Calculate ∆H° for the reaction.
Solution :
Kp1 = 8.19 × 102;
T1 = 298 K
Kp1 = 8.19 × 102;
T1 = 298 K
Kp2 = 4.16 × 10-1;
T2 = 498 K
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 18

Question 51.
The partial pressure of carbon dioxide in the reaction CaCO3(s) ⇌ CaO(s) + CO2(g) is 1.017 × 10-3 atm at 500°C. Calculate Kp at 600°C for the reaction. H for the reaction is 181 KJ mol-1 and does not change in the given range of temperature.
Solution:
PCO2 = 1.017 × 10-3 atm
T = 500°C;
Kp = PCO2
∴ Kp1 = 1.017 × 10-3;
T = 500 + 273 = 773 K
Kp2 = ?
T = 600 + 273 = 873 K
∆H° = 181 KJ mol-1
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 19

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

11th Chemistry Guide Physical and Chemical Equilibrium Additional Questions and Answers

I.Choose the best answer:

Question 1.
For which of the following Kp is less than Kc?
a) N2O4 ⇌ 2NO2
b) N2 + 3H2 ⇌ 2NH3
c) H2 + I2 ⇌ 2HI
d) CO + H2O ⇌ CO2 + H2
Answer:
b) N2 + 3H2 ⇌ 2NH3

Question 2.
In which of the following reaction, the value of Kp will be equal to Kc?
a) H2 + I2 ⇌ 2HI
b) PCl5 ⇌ PCl3 + Cl2
c) 2NH3 ⇌ N2 + 3H2
d) 2SO2 +O2 ⇌ 2SO3
Answer:
a) H2 + I2 ⇌ 2HI

Question 3.
For homogeneous gas reaction 4NH3 + 5O2 ⇌ 4NO + 6H2O. The equilibrium constant Kc has the unit
a) (concentration)1
b) (concentration)1
c) (concentration)9
d) (concentration)10
Answer:
a) (concentration)1

Question 4.
The reaction, 2SO2(g) + O2(g) ⇌ 2SO3(g) is carried out in a 1 dm3 vessel and 2 dm3 vessel separately. The ratio of the reaction velocities will be
a) 1 : 8
b) 1 : 4
c) 4 : 1
d) 8 : 1
Answer:
d) 8 : 1

Question 5.
Kp for the following reaction at 700 K is 1.3 × 10-3 atm-1. The Kc same temperature for the reaction. 2SO2 + O2 ⇌ 2SO3 will be
a) 1.1 × 10-2
b) 3.1 × 10-2
c) 5.2 × 10-2
d) 7.4 × 10-2
Answer:
d) 7.4 × 10-2

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 6.
The equilibrium constant expression for the equilibrium :
2NH2(g) + 2O2(g) ⇌ N2O(g) + 3H2O(g) is
a) Kc = \(\frac{\left[\mathrm{N}_{2} \mathrm{O}\right]\left[\mathrm{H}_{2} \mathrm{O}\right]^{3}}{\left[\mathrm{NH}_{3}\right]\left[\mathrm{O}_{2}\right]}\)

b) Kc = \(\frac{\left[\mathrm{H}_{2} \mathrm{O}\right]^{3}\left[\mathrm{~N}_{2} \mathrm{O}\right]}{\left[\mathrm{NH}_{3}\right]^{2}\left[\mathrm{O}_{2}\right]^{2}}\)

c) Kc = \(\frac{\left[\mathrm{NH}_{3}\right]^{2}\left[\mathrm{O}_{2}\right]^{2}}{\left[\mathrm{~N}_{2} \mathrm{O}\right]\left[\mathrm{H}_{2} \mathrm{O}\right]^{3}}\)

d) Kc = \(\frac{\left[\mathrm{NH}_{3}\right]\left[\mathrm{O}_{2}\right]}{\left[\mathrm{N}_{2} \mathrm{O}\right]\left[\mathrm{H}_{2} \mathrm{O}\right]}\)
Answer:
b) Kc = \(\frac{\left[\mathrm{H}_{2} \mathrm{O}\right]^{3}\left[\mathrm{~N}_{2} \mathrm{O}\right]}{\left[\mathrm{NH}_{3}\right]^{2}\left[\mathrm{O}_{2}\right]^{2}}\)

Question 7.
For the system 3A + 2B ⇌ C, the expression for equilibrium constant is
a) \(\frac{[3 \mathrm{~A}][2 \mathrm{~B}]}{[\mathrm{C}]}\)

b) \(\frac{[\mathrm{C}]}{[3 \mathrm{~A}][2 \mathrm{~B}]}\)

c) \(\frac{[\mathrm{A}]^{3}[\mathrm{~B}]^{2}}{[\mathrm{C}]}\)

d) \(\frac{[\mathrm{C}]}{[\mathrm{A}]^{3}[\mathrm{~B}]^{2}}\)
Answer:
d) \(\frac{[\mathrm{C}]}{[\mathrm{A}]^{3}[\mathrm{~B}]^{2}}\)

Question 8.
For the reaction PCl3(g) + Cl2(g) ⇌ PCl5(g) at 250°C, the value of Kc is 26, then the value of Kp at the same temperature will be
a) 0.61
b) 0.57
c) 0.83
d) 0.46
Answer:
a) 0.61

Question 9.
The equilibrium constant for the reaction N2(g) + O2(g) ⇌ 2NO(g) at temperature T is 4 × 10-4. The value of Kc for the reaction NO(g) ⇌ 1/2 N2(g) + 1/2 O2(g) at the same temperature is ___________.
a) 4 × 10-4
b) 50
c) 2.5 × 102
d) 0.02
Answer:
b) 50

Question 10.
In which of the following equilibria, the value of Kp is less than Kc?
a) H2 + I2 ⇌ 2HI
b) N2 + 3 H2 ⇌ 2NH3
c) N2 + O2 ⇌ 2NO
d) CO + H2O ⇌ CO2 + H2
Answer:
b) N2 + 3 H2 ⇌ 2NH3

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 11.
In the reversible reaction A + B ⇌ C + D. The concentration of each C and D at equilibrium was 0.8-mole lit, then the equilibrium constant will be
a) 6.4
b) 0.64
c) 1.6
d) 16.0
Answer:
d) 16.0

Question 12.
The Kc for H2(g) + I2(g) ⇌ 2 HI(g), is 64. If the volume of the container is reduced to one – half of its original volume, the value of the equilibrium constant will be
a) +28
b) 64
c) 32
d) 16
Answer:
b) 64

Question 13.
For the reaction C(s) + CO2(g) ⇌ 2CO (g), the partial pressure of CO2 and CO are 2.0 and 4.0 atm respectively at equilibrium. The Kp for the reaction is
a) 0.5
b) 4.0
c) 8.0
d) 32.0
Answer:
c) 8.0

Question 14.
When the rate of forward reaction becomes equal to backward reaction, this state is termed as
a) chemical equilibrium
b) Reversible state
c) Equilibrium
d) All of these
Answer:
d) All of these

Question 15.
The equilibrium constant of the reaction H2(g) + I2(g) ⇌ 2 HI(g) is 64. If the volume of the container is reduced to one – fourth of its original volume, the value of the equilibrium constant will be
a) 16
b) 32
c) 64
d) 128
Answer:
c) 64

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 16.
For the reaction PCl3(g) + Cl2(g) ⇌ PCl5(g), the position of equilibrium can be
shifted to the right by _______.
a) increasing the temperature
b) Doubling the volume
c) Addition of Cl2 at constant volume
d) Addition of equimolar quantities of PCl3 and PCl5
Answer:
b) Doubling the volume

Question 17.
For the reaction 2 NOCl(g) ⇌ 2 NO(g) + Cl2(g), Kc at 427 is 3 × 10-6 L mol-1. The value of Kp is nearly
a) 7.50 × 10-5
b) 2.50 × 10-5
c) 2.50 × 10-4
d) 1.72 × 10-4
Answer:
d) 1.72 × 10-4

Question 18.
Rate of reaction curve for equilibrium can be like [rf = forward rate, rb = backward rate]
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 20
Answer:
a) Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 21

Question 19.
For a reaction, N2 + 3H2 ⇌ 2NH3(g), the value of Kc does not depend upon
A) initial concentration of the reactants
B) pressure
C) temperature
D) Catalyst
a) only C
b) A, B, C
c) A, B, C
d) A, B, C, D
Answer:
c) A, B, C

Question 20.
2NO2 ⇌ 2NO + O2, K = 1.6 × 10-12 NO + \(\frac{1}{2}\)O2 ⇌ NO2; K’ = ?
a) K’ = \(\frac{1}{\mathrm{~K}^{2}}\)
b) K’ = \(\frac{1}{\mathrm{~K}}\)
c) K’ = \(\frac{1}{\sqrt{\mathrm{K}}}\)
d) None of these
Answer:
c) K’ = \(\frac{1}{\sqrt{\mathrm{K}}}\)

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 21.
At 1000 K, the value of Kp for the reaction, A(g) + 2B(g) ⇌ 3C (g) + D(g) is 0.05 atm. The value of Kc in terms of R would be
a) 20000 R
b) 0.02 R
c) 5 × 10-5 R
d) 5 × 10-5 × R-1
Answer:
d) 5 × 10-5 × R-1

Question 22.
In a chemical equilibrium, the rate constant for the backward reaction is 7.5 x 10-4 and the equilibrium constant is 1.5. The rate constant for the forward reaction
a) 2 × 10-3
b) 5 × 10-4
c) 1.12 × 10-3
d) 9.0 × 10-4
Answer:
c) 1.12 × 10-3

Question 23.
A reversible reaction is one which
a) Proceeds in one direction
b) proceeds in both direction
c) proceeds spontaneously
d) All the statements are wrong
Answer:
b) proceeds in both direction

Question 24.
The equilibrium constant in a reversible reaction at a given temperature
a) depends on the initial concentration of the reactants
b) depends on the concentration of the products at equilibrium
c) does not depend on the initial concentrations
d) It is not characteristic of the reaction
Answer:
c) does not depend on the initial concentrations

Question 25.
For the system A(g) + 2B(g) ⇌C (g), the equilibrium concentrations are (A) 0.06 mole / lit (B) 0.12 mole / lit and (C) 0.216 mole / lit. The Keq for the reaction is
a) 250
b) 416
c) 4 × 10-3
d) 125
Answer:
a) 250

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 26.
A chemical reaction is at equilibrium when
a) Reactants are completely transformed into products
b) The rates of forward and backward reactions are equal
c) Formation of products is minimized
d) Equal amounts of reactants and products are present
Answer:
b) The rates of forward and backward reactions are equal

Question 27.
Partial pressures of A, B, C and D on the basis of gaseous system A + 2B ⇌ C + 3D are A = 0.20, B = 0.10, C = 0.30 and D = 0.50 atm. The numerical value of equilibrium constant is _______.
a) 11.25
b) 18.75
c) 5
d) 3.75
Answer:
b) 18.75

Question 28.
Molar concentration of 96 g of O2 contained in a 2 L vessel is ______.
a) 16 mol / L
b) 1.5 mol / L
c) 4 mol / L
d) 24 mol / L
Answer:
b) 1.5 mol / L

Question 29.
According to law of mass action rate of a chemical reaction is proportional to
a) concentration of reactants
b) molar concentration of reactants
c) concentration of products
d) molar concentration of products
Answer:
b) molar concentration of reactants

Question 30.
The equilibrium constant of the reaction SO2(g) + \(\frac{1}{2}\) O2(g) ⇌ SO3 (g) is 4 × 10-3 atm-1/2. The equilibrium constant of the reaction 2SO3(g) ⇌ 2SO2(g) + O2(g) would be
a) 250 atm
b) 4 × 103 atm
c) 0.25 × 104 atm
d) 6.25 × 104 atm
Answer:
d) 6.25 × 104 atm

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 31.
The rate constant for forward and backward reactions of the hydrolysis of ester are 1.1 × 10-2 and 1.5 × 10-3 per minute respectively. The equilibrium constant for the reaction is ___________.
a) 4.33
b) 5.33
c) 6.33
d) 7.33
Answer:
d) 7.33

Question 32.
The active mass of 64 g of HI is a two litre of flask would be
a) 2
b) 1
c) 5
d) 0.25
Answer:
d) 0.25

Question 33.
At a certain temperature, 2HI ⇌ H2 + I2. Only 50 % HI is dissociated at equilibrium. The equilibrium constant is
a) 0.25
b) 1.0
c) 3.0
d) 0.50
Answer:
a) 0.25

Question 34.
Unit of equilibrium constant for the reversible reaction, H2 + I2 ⇌ 2HI is ________.
a) mol-1 litre
b) mol-2 litre
c) mol litre-1
d) none of these
Answer:
d) none of these

Question 35.
For the reaction
CO(g) + \(\frac{1}{2}\)O2(g) ⇌ CO2(g), Kp/Kc is _______.
a) RT
b) (RT)-1
c) (RT)-1/2
d) (RT)1/2
Answer:
c) (RT)-1/2

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 36.
The following equilibrium are given
N2 +3H2 ⇌ 2NH2 ………K1
N2 + O2 ⇌ 2N0 ………….K2
H2 + 1/2 O2 ⇌ H2O …….. K3
The equilibrium constant of the reaction.
2 NH3 + 5/2 O2 ⇌ 2NO + 3H2O, in terms of K1, K2 and K3 is _________.
a) \(\frac{\mathbf{K}_{1} \mathbf{K}_{2}}{\mathbf{K}_{3}}\)

b) \(\frac{\mathrm{K}_{1} \mathrm{~K}_{3}^{2}}{\mathrm{~K}_{2}}\)

c) \(\frac{\mathrm{K}_{2} \mathrm{~K}_{3}^{2}}{\mathrm{~K}_{1}}\)

d) K1 K2 K3
Answer:
c) \(\frac{\mathrm{K}_{2} \mathrm{~K}_{3}^{2}}{\mathrm{~K}_{1}}\)

Question 37.
For the reaction
2NO2(g) ⇌ 2NO(g) + O2(g) Kc = 1.8 × 10-6 at 184°C and R = 0.083 Jk-1 mol-1. When Kp and are compared at 184C, it
is found that
a) Kp > Kc
b) Kp < Kc
c) Kp – Kc
d) Kp × Kc( depends upon pressure of gases)
Answer:
a) Kp > Kc

Question 38.
The rate of forward reaction is two times that of reverse reaction at a given temperature and identical concentration. K equilibrium is
a) 2.5
b) 2.0
c) 0.5
d) 1.5
Answer:
b) 2.0

Question 39.
In a reaction A+B ⇌ C+D,the concentrations of A, B, C and D [in mole/lit] are 0.5, 0.8, 0.4 & 1.0 respectively. Th. equilibrium constant is
a) 0.1
b) 1.0
c) 10
d) ∞
Answer:
b) 1.0

Question 40.
For the following thre. reactions 1, 2 and 3 equilibrium constants are given:
1. CO(g) + H2O(g) ⇌ CO(g) + H2(g); K1
2.CH4(g) + H2O(g) ⇌ CO + 3H(g); K2
3. CH4(g) + 2H2O(g) ⇌ CO(g) + 4H2(g); K3
Which of the following relations is correct?
a) K1√K2 = K3
b) K2K3 = K1
c) K3 = K1K2
d) K3 = K23 K12
Answer:
c) K3 = K1K2

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 41.
4 moles of A is mixed with 4 moles of B. At equilibrium for the reaction A + B ⇌ C + D. 2 moles of C and D is formed. The equilibrium constant for the reaction will be
a) \(\frac{1}{4}\)
b) \(\frac{1}{2}\)
c) 1
d) 4
Answer:
c) 1

Question 42.
In a reaction PCl5 ⇌ PCl3 + Cl2 degree of dissociation is 30%. If Initial moles of PCl5 is one then total moles at equilibrium is
a) 1.3
b) 0.7
c) 1.6
d) 1.0
Answer:
a) 1.3

Question 43.
When 3 moles of A and 1 mole of B are mixed in 1 lit vessel, the following reaction takes place A(g) + B(g) ⇌ 2C(g), 1.5 moles of ‘C’ are formed. The equilibrium constant for the reaction is
a) 0.12
b) 0.25
c) 0.50
d) 4.0
Answer:
d) 4.0

Question 44.
In which of the following, the reaction proceeds towards completion
a) K = 103
b) K = 10-2
c) K = 10
d) K = 1
Answer:
a) K = 103

Question 45.
Two moles of NH3 when put into a previously evacuated vessel (1L) partially dissociate into N2 and H2. If at equilibrium one mole of NH3 is present, the equilibrium constant is ________.
a) \(\frac{3}{4}\) mol2 lit-2

b) \(\frac{27}{64}\) mol2 lit-2

c) \(\frac{27}{32}\) mol2 lit-2

d) \(\frac{27}{16}\) mol2 lit-2
Answer:
d) \(\frac{27}{16}\) mol2 lit-2

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 46.
For the reaction N2(g) + O2(g) ⇌ 2NO(g) the value of Kc at 800°C is 0.1. When the equilibrium concentration of both the reactions is 0.5 mol, what is the value of Kp at the same temperature?
a) 0.5
b) 0.1
c) 0.01
d) 0.025
Answer:
b) 0.1

Question 47.
28 g of N2(g) and 6g of H2(g) were mixed at equilibrium 17 g NH3 was produced. The weight of N2 and H2 at equilibrium are respectively.
a) 11g, 0g
b) 1g, 3g
c) 14g, 3g
d) 11g, 3g
Answer:
c) 14g, 3g

Question 48.
2SO3 ⇌ 2SO2 + O2 If Kc = 100, α = 1, half of the reaction is completed, the concentration of SO3 and SO2 are equal, the concentration of O2 is _________.
a) 0.001 M
b) \(\frac{1}{2}\) SO2
c) 2 times of SO2
d) Data in complete
Answer:
d) Data in complete

Question 49.
For reaction HI ⇌ \(\frac{1}{2}\)H2 + \(\frac{1}{2}\)I2 value of Kc is \(\frac{1}{8}\), then value of K is \(\frac{1}{8}\) for H2 + I2 ⇌ 2HI.
a) \(\frac{1}{64}\)
b) 64
c) \(\frac{1}{8}\)
d) 8
Answer:
b) 64

Question 50.
2 moles of PCl5 were heated in a closed vessel of 2 liter capacity. At equilibrium, 40% of PCl5 is dissociated into PCl3 and Cl2. The value of equilibrium constant is
a) 0.266
b) 0.53
c) 2.66
d) 5.3
Answer:
a) 0.266

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 51.
For a reaction H2 + I2 ⇌ 2HI at 721 k, the value of equilibrium constant is 50. If 0.5 mol each of H2 and I2 is added to the system the value of equilibrium constant will be
a) 40
b) 60
c) 50
d) 30
Answer:
c) 50

Question 52.
In a reaction the rate of reaction is proportional to its active mass, this statement is known as
a) Law of mass action
b) Le – Chatelier principle
c) Faradays’s law of electrolysis
d) law of constant proportion
Answer:
b) Le – Chatelier principle

Question 53.
In a chemical equilibrium A + B ⇌ C + D, when one mole each of the two reactants are mixed, 0.6 mole each of the products are formed. The equilibrium constant calculated is
a) 1
b) 0.36
c) 2.25
d) \(\frac{4}{9}\)
Answer:
c) 2.25

Question 54.
Under a given set of experimental conditions, with an increase in the concentration of the reactants, the rate of a chemical reaction.
a) Decreases
b) Increases
c) Remains unaltered
d) First decreases and then increases
Answer:
c) Remains unaltered

Question 55.
A + B ⇌ C + D, If finally the concentrations of A and B are both equal but at equilibrium concentration of D will be twice of that of A then what will be the equilibrium constant of reaction.
a) \(\frac{4}{9}\)
b) \(\frac{9}{4}\)
c) \(\frac{1}{9}\)
d) 4
Answer:
d) 4

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 56.
Theory of ‘active mass’ indicates that the rate of chemical reaction is directly proportional to the ___________.
a) Equilibrium constant
b) Properties of reactants
c) Volume of apparatus
d) Concentration of reactants
Answer:
d) Concentration of reactants

Question 57.
In the reaction, A + B ⇌ 2C, at equilibrium the concentration of A and B is 0.20 mol L-1 each and that of C was found to be 0.60 mol L-1. The equilibrium constant of the reaction is
a) 2.4
b) 18
c) 4.8
d) 9
Answer:
d) 9

Question 58.
The rate at which substances react depends on their _______.
a) Atomic weight
b) Molecular weight
c) Equivalent weight
d) Active mass
Answer:
c) Equivalent weight

Question 59.
If in the reaction N2O4 ⇌ 2NO2, α is that part of N2O4 which dissociates, then the number of moles at equilibrium will be
a) 3
b) 1
c) (1- α)2
d) (1 + α)
Answer:
d) (1 + α)

Question 60.
On decomposition of NH4HS, the following equilibrium is established NH4HS(s) ⇌ NH3(g) + H2S(g). If the total pressure is P atm, then the equilibrium constant Kp is equal to _______.
a) P atm
b) P2 atm2
c) \(\frac{\mathrm{P}^{2}}{4}\) atm2
d) 2P atm
Answer:
c) \(\frac{\mathrm{P}^{2}}{4}\) atm2

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 61.
Some gaseous equilibrium are given below:
i) CO + H2O ⇌ CO2 + H2
ii) 2CO + O2 ⇌ 2CO
iii) 2H2 + O2 ⇌ 2H3O
find out the relation between equilibrium constants.
a) K = K1K2
b) K = (K1K2)2
c) K = (K1K2)–\(\frac{1}{2}\)
d) K = \(\left(\frac{\mathrm{K}_{1}}{\mathrm{~K}_{2}}\right)^{\frac{1}{2}}\)
Answer:
d) K = \(\left(\frac{\mathrm{K}_{1}}{\mathrm{~K}_{2}}\right)^{\frac{1}{2}}\)

Question 62.
Kc = 9 for the reaction A + B ⇌ C + D. If A and B are taken In equal amounts, then amount of ‘C’ in equilibrium is
a) 1
b) 0.25
c) 0.75
d) none of these
Answer:
c) 0.75

Question 63.
In the reaction C(S) + CO2(g) ⇌ 2CO(g) the equilibrium pressure is 12 atm. If 50 % of CO2 reacts, then Kp will be ________.
a) 12 atm
b) 16 atm
c) 20 atm
d) 24 atm
Answer:
b) 16 atm

Question 64.
For the following gases equilibrium, N2O4(g) ⇌ 2NO2(g) Kp is found to be equal to Kc. This is attained when,
a) 0°C
b) 273 k
c) 1 k
d) 12.19 k
Answer:
d) 12.19 k

Question 65.
Consider the following reversible gaseous reactions {At 298 K)
a) N2O4 ⇌ 2NO2
b) 2SO2 + O2 ⇌ 2SO3
c) 2HI ⇌ H2 + I2
d) X + Y ⇌ 4Z
Answer:
a) N2O4 ⇌ 2NO2

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 66.
For the reaction A + 2B ⇌ 2C at equilibrium [C] = 1.4 M, [A]0 = 1 M, [B]0 = 2M, [C]0 = 3 M. The value of Kc is .
a) 0.084
b) 8.4
c) 84
d) 840
Answer:
a) 0.084

Question 67.
For the reaction H2(g) + I2(g) ⇌ 2HI(g). Kc = 66.9 at 350°C and Kc = 50.0 at 448°C. The reaction has
a) ∆H = +ve
b) ∆H = -ve
c) ∆H = zero
d) ∆H = not found the signs.
Answer:
b) ∆H = -ve

Question 68.
In an equilibrium reaction H2(g) + I2(g) ⇌ 2HI(g), ∆H = -3000 calories, which factor favours dissociation of HI
a) Low temperature
b) High pressure
c) High temperature
d) Low pressure
Answer:
c) High temperature

Question 69.
In an equilibrium reaction for which ∆G°= 0, the equilibrium constant K Is
a) 0
b) 1
c) 2
d) 10
Answer:
b) 1

Question 70.
Consider the following reversible reaction at equilibrium, 2H2O(g) ⇌ 2H2(g) + O2(g). Which one of the following ∆H = 241. 7 kJ changes in a conditions will lead to maximum decomposition of H2O(g)?
a) Increasing both temperature and pressure
b) Decreasing temperature and increasing pressure
c) Increasing temperature and decreasing pressure
d) Increasing temperature at constant pressure.
Answer:
c) Increasing temperature and decreasing pressure

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 71.
In which of the following system doubling the volume of the container causes a shift to the right.
a) H2(g) + Cl2(g) ⇌ 2HCl(g)
b) 2CO(g) + O2(g) ⇌ 2CO2(g)
c) N2(g) + 3H2(g) ⇌ 2NH3(g)
d) PCl5(g) ⇌ PCl3(g) + Cl2(g)
Answer:
d) PCl5(g) ⇌ PCl3(g) + Cl2(g)

Question 72.
∆G° (HI, g) ≈ 1.7 kJ. What is the equilibrium constant at 25° C for 2HI(g) ⇌ H2(g) + I2(g)
a) 24.0
b) 3.9
c) 2.0
d) 0.5
Answer:
d) 0.5

Question 73.
In the reaction A2(g) + 4B2(g) ⇌ 2AB4 ∆H < 0 the formation of AB4 is will, be favoured at
a) Low temperature, high pressure
b) High temperature, low pressure
c) Low temperature, low pressure
d) High temperature, high pressure
Answer:
a) Low temperature, high pressure

Question 74.
N2 + 3H2 ⇌ 2NH3. If temperature of following equilibrium reaction increases then the reaction.
a) Shifts Right side
b) Shifts left side
C) Remains unchanged
d) No change
Answer:
b) Shifts left side

Question 75.
Consider the equilibrium N2(g) + 3H2(g) ⇌ 2NH3 ∆H = -93.6 kJ. The maximum yield of ammonia is obtained by
a) Decrease of temperature and increase of pressure.
b) Increase of temperature and decreases of pressure.
c) Decrease of both the temperature and pressure
d) Increase of both the temperature and pressure
Answer:
a) Decrease of temperature and increase of pressure.

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 76.
H2(g) + I2(g) ⇌ 2HI(g) ∆H = +q cal, then formation of HI
a) Is favoured by lowering the temperature
b) Is favoured by increasing the pressure
c) Is unaffected by change in pressure
d) Is unaffected by change in temperature
Answer:
c) Is unaffected by change in pressure

Question 77.
The formation of SO3 takes place according to the following reaction, 2SO2 + O2 ⇌ 2SO3; ∆H = 45.2 k cal. The formation of SO3 is favoured by
a) Increasing in temperature
b) Removal of oxygen
c) Increase of volume
d) Increase of pressure
Answer:
d) Increase of pressure

Question 78.
Which of the following equilibrium is not shifted by an increase in the pressure?
a) H2(g) + 3H2(g) ⇌ 2HI(g)
b) N2(g) + 3H2(g) ⇌ 2NH3(g)
c) 2CO(g) + O2(g) ⇌ 2CO2(g)
d) 2C(g) + O2(g) ⇌ 2CO(g)
Answer:
a) H2(g) + 3H2(g) ⇌ 2HI(g)

Question 79.
Consider the heterogeneous equilibrium in a closed container. NH4HS(s) ⇌ NH3(g) + H2S(g) if more NH4HS is added to the equilibrium
a) Partial pressure of NH3 increases
b) Partial pressure of H2S increases
c) Total pressure in the container increases
d) No effect on partial pressure of NH3 and H2S
Answer:
d) No effect on partial pressure of NH3 and H2S

Question 80.
According to Le – Chatelier’s principle adding heat to a solid and liquid in equilibrium with endothermic nature will cause the ____________.
a) Temperature to rise
b) Temperature to fall
c) Amount of solid to decrease
d) Amount of liquid to decrease
Answer:
c) Amount of solid to decrease

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 81.
According to Le-chatelier’s principle, adding heat to a solid to liquid in equilibrium will causes the
a) temperature to increase
b) temperature to decrease
c) amount of liquid to increase
d) amount of solid to increase
Answer:
c) amount of liquid to increase

Question 82.
For the reaction A + B + Q ⇌ C + D, if the temperature is increased, then concentration of the products will
a) increase
b) decrease
c) Remain same
d) become zero
Answer:
a) increase

Question 83.
H2(g) + I2(g) ⇌ 2HI(g). In this reaction when pressure increases, the reaction direction
a) does not change
b) is forward
c) is backward
d) decreases
Answer:
a) does not change

Question 84.
Which of the following factor is shifted the reaction PCl3 + Cl2 ⇌ PCl5 at the left side?
a) Adding PCl5
b) increase pressure
c) constant temperature
d) catalyst
Answer:
a) Adding PCl5

Question 85.
The rate of reaction of which of the following is not affected by pressure?
a) PCl3 + Cl2 ⇌ PCl5
b) N2 + 3 H2 ⇌ 2NH3
c) N2 + O2 ⇌ 2NO
d) 2 SO2 + O2 ⇌ 2 SO3
Answer:
c) N2 + O2 ⇌ 2NO

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 86.
Which reaction is not affected by change in pressure?
a) H2 + I2 ⇌ 2HI
b) 2 C + O2 ⇌ 2CO
c) N2 + 3 H2 ⇌ 2NH3
d) PCl5 ⇌ PCl3 + Cl2
Answer:
a) H2 + I2 ⇌ 2HI

Question 87.
Which of the following reactions proceeds at low pressure?
a) N2 + 3H2 ⇌ 2NH3
b) H2 + I2 ⇌ 2HI
c) PCl5 ⇌ PCl3 + Cl2
d) N2 + O2 ⇌ 2NO
Answer:
c) PCl5 ⇌ PCl3 + Cl2

Question 88.
In the following reaction PCl5 ⇌ PCl3(g) + Cl2(g) at constant temperature, rate of backward reaction, is increased by
a) inert gas mixed at constant volume
b) Cl2 gas mixed at constant volume
c) inert gas mixed at constant pressure
d) PCl5 mixed in constant volume
Answer:
b) Cl2 gas mixed at constant volume

Question 89.
On cooling of following system at equilibrium CO2(s) ⇌ CO2(g)
a) There is no effect on the equilibrium state
b) more gas is formed
c) more gas solidifies
d) None
Answer:
c) more gas solidifies

Question 90.
On the velocity in a reversible reaction the correct explanation of the effect of catalyst is _______.
a) it provides a new reaction path of low activation energy
b It increases a kinetic energy of the reacting molecules
c) it displaces the equilibrium state on right side
d) it decreases the velocity of backward reaction
Answer:
a) it provides a new reaction path of low activation energy

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 91.
According to Le – Chatelier’s principle, if heat is given to solid – liquid system, then
a) Quantity of solid will reduce
b) Quantity of liquid will reduce
c) increase in temperature
d) decrease in temperature
Answer:
a) Quantity of solid will reduce

Question 92.
In a gives system, water and ice are in equilibrium, if pressure is applied to the system then .
a) more of ice is formed
b) amount of ice and water will remain same
c) more of ice is melted
d) either (a) or (c)
Answer:
c) more of ice is melted

Question 93.
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 22
Answer:
b) Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 23

Question 94.
The value of ∆G° for a reaction in aqueous phase having Kc = 1, would be
a) – RT
b) -1
c) 0
d) + RT
Answer:
c) 0

Question 95.
The equilibrium constants for the reaction, Br2 ⇌ 2 Br at 500 K and 700 K are 1 × 10-10 and 1 × 10-5 respectively. The reaction is
a) endothermic
b) exothermic
c) fast
d) slow
Answer:
a) endothermic

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 96.
In the reaction A2(g) + 4 B2(g) ⇌ 2AB4(g), ∆H < 0, the decomposition of AB4(g) will be favoured at
a) low temperature and high pressure
b) high temperature and low pressure
c) low temperature and low pressure
d) high temperature and high pressure
Answer:
c) low temperature and low pressure

Question 97.
The equilibrium constant for the reaction N2(g) + O2(g) ⇌ 2NO (g) is 4 × 10-4 at 200 K. In the presence of a catalyst the equilibrium is attained 10 times faster. Therefore the equilibrium constant in pressure of the catalyst at 200 K is
a) 4 × 10-3
b) 4 × 10-4
c) 4 × 10-5
d) None
Answer:
b) 4 × 10-4

Question 98.
Change in volume of the system does not alter the number of moles in which of the following equilibrium.
a) N2(g) + O2(g) ⇌ 2 NO (g)
b) PCl5(g) ⇌ PCl3(g) + Cl2(g)
c) N2(g) + 3H2(g) ⇌ 2 NH3(g)
d) SO2Cl2(g) ⇌ SO2(g) + Cl2(g)
Answer:
a) N2(g) + O2(g) ⇌ 2NO2 (g)

Question 99.
In which of the following equilibrium reactions the equilibrium would shift to the right, if total pressure is increased
a) N2 + 3H2 ⇌ 2 NH3
b) H2 + I2 ⇌ 2HI
c) H2 + Cl2 ⇌ 2 HCl
d) N2O4 ⇌ 2NO
Answer:
a) N2 + 3H2 ⇌ 2 NH3

Question 100.
The graph in K (eq) vs \(\frac{1}{T}\) relates for a reaction must be
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 24
a) Exothermic
b) Endothermic
c) ∆H is negligible
d) High spontaneous at ordinary temperature
Answer:
a) Exothermic

Question 101.
Which of the following statements is cor¬rect for a reversible process in state of equilibrium?
a) ∆G° = -2.30 RT log K
b) ∆G° = 2.30 RT log K
c) ∆G = -2.30 RT log K
d) ∆G = 2.30 RT log K
Answer:
a) ∆G° = -2.30 RT log K

Question 102.
Which of the following is a characteristic of a reversible reaction?
a) Number of moles of reactants and products are equal
b) it can be influenced by a catalyst
c) it can never proceed to completion
d) none of the above
Answer:
c) it can never proceed to completion

Question 103.
The equilibrium constant in a reversible reaction at a given temperature
a) depends on the initial concentration of the reactants
b) depends on the concentration of the products at equilibrium
c) does not depend on the initial concentration
d) it is not characteristic of the reaction
Answer:
c) does not depend on the initial concentration

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

II. Very short question and answers(2 Marks):

Question 1.
What are reversible reactions?
Answer:
Reactions in which the products can react to give back reactants under suitable conditions are called reversible reactions.

Question 2.
What are irreversible reactions?
Answer:
Reactions in which the products formed do not react to give back reactants under normal conditions are called irreversible reactions.

Question 3.
Why the chemical equilibrium is referred to as Dynamic Equilibrium?
Answer:
At equilibrium the forward and the backward reactions are proceeding at the same rate and no macroscopic change is observed. So chemical equilibrium is often called as dynamic equilibrium.

Question 4.
What is equilibrium constant?
Answer:
The equilibrium constant Kc may be defined as the ratio of product of the active masses of the products to that of the reactants.

Question 5.
Write the Applications of equilibrium constant?
Answer:
The knowledge of equilibrium constant helps us in

  • predicting the extent of a reaction, predicting the direction in which the net reaction is taking place and
  • calculation of equilibrium constants and concentration of the reactants and products.

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 6.
What is Le – Chatelier’s principle?
Answer:
It states that “If a system at equilibrium is subjected to a change of concentration, pressure or temperature, then the equilibrium is shifted in such a ways to nullify the effect of that disturbance.

Question 7.
For the H2(g) + I2(g) ⇌ 2HI(g) reaction the value of Kc at 717 K is 48. If at a particular instant, the concentration of H2, I2, and HI is 0.2 mol lit-1 and 0.6 mol lit-1 respectively, then calculate Q and predict the direction of reaction.
Solution:
Q = \(\frac{\left[\mathrm{H}_{1}\right]^{2}}{\left[\mathrm{H}_{2}\right]\left[\mathrm{I}_{2}\right]}=\frac{0.6 \times 0.6}{0.2 \times 0.2}\) = 9
Q < Kc, the reaction will proceed in the forward direction.

Question 8.
Define Degree of dissociation.
Answer:
The fraction of the total number of moles of the reactants are dissociated.
Degree of dissociation ‘x’ =
‘x’ = \(\frac{\text { no.of moles dissociated }}{\text { Total no. of moles present initially }}\)

Question 9.
Dissociation of PCl5 decreases in presence of increase in Cl2, Why?
Answer:

  1. The dissociation equilibrium of PCl5 in gaseous state is written as PCl5(g) ⇌ PCl3(g) + Cl2(g)
  2. In a chemical equilibrium increasing the concentration of the products results in shifting the equilibrium in favour of the reactants. So in the presence of increased Cl2 reversed reaction only favoured.
  3. Hence dissociation of PCl5 decreases in presence of increase in Cl2.

Question 10.
The equilibrium constant for Kc for A(g) ⇌ B(g) is 2.5 × 10-2 . The rate constant of the forward reaction is 0.05 sec-1. Calculate the rate constant of the reverse reaction.
Answer:
Kc = 2.5 × 10-2;
Kf = 0.05 sec-1
Kc = \(\frac{\mathrm{K}_{\mathrm{f}}}{\mathrm{K}_{\mathrm{r}}}\)
= \(\frac{0.05}{2.5 \times 10^{-2}}\) = 2
Rate constant of the reverse reaction,
Kr = 2 sec-1.

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 11.
The equilibrium constant for the reaction 2SO3(g) ⇌ 2SO2(g) + O2(g) is 0.15 mol dm-3 at 900K. Calculate the equilibrium constant for the reaction 2SO2(g) + O2(g) ⇌ 2SO3(g) at the same temperature. 2SO3(g) ⇌ 2SO2(g) + O2(g).
Answer:
Kc = \(\frac{\left[\mathrm{SO}_{2}\right]^{2}\left[\mathrm{O}_{2}\right]}{\left[\mathrm{SO}_{3}\right]^{2}}\) = 0.15
K’ = \(\frac{1}{\mathrm{~K}_{\mathrm{c}}}=\frac{1}{0.15}\)
= 6.6 mole dm-3
K’ = 6.6 mole dm-3

III. Short question and answers(3 Marks):

Question 1.
What is solid – liquid equilibrium? Give example.
Answer:

  • The equilibrium between solid and liquid at its melting point (or freezing point) at normal atmospheric pressure is called solid-liquid equilibrium.
  • If some ice-cubes along with water are placed in a thermos flask (at 00 C and 1 atm), then there will be no change in the mass of ice and water.
  • At equilibrium,
    Rate of melting of ice = Rate of freezing of water
    H2O(s) ⇌ H2O(l)

Question 2.
What is liquid – vapour equilibrium?
Answer:
The equilibrium of a liquid with its gas at its boiling point at 1 atm pressure is called liquid – vapour equilibrium.
Rate of evaporation = Rate of condensation
H2O(l) ⇌ H2O(g).

Question 3.
What is Solid – vapour equilibrium?
Answer:

  • When solid iodine is placed in a closed transparent vessel, after sometime the vessel gets filled up with violet vapour.
  • The intensity of the colour increases and finally becomes constant, i.e., equilibrium is attained.
    I2(s) ⇌ I2(g)

Question 4.
What are Homogeneous and Heterogeneous equilibriums?
Answer:
Homogeneous equilibrium:
In a homogeneous equilibrium, all the reactants and products are in the same phase.
Example:
H2(g) + I2(g) ⇌ 2HI (g)
In the above equilibrium, H2, I2, and HI are in the gaseous state.
Similarly, for the following reactions,
CH3COOCH3(aq) + H2O(aq) ⇌ CH3COOH (aq) + CH3OH (aq) all the reactants and products are in homogenous solution phase.

Heterogeneous equilibrium:
If the reactants and products are present in different phases, it is known as heterogeneous equilibrium.
Example:
H2O(l) ⇌ H2O (g)
CaCO3(s) ⇌ CaO(s) + CO2(g).

Question 5.
What is Law of mass action?
Answer:
“At any instant, the rate of a chemical reaction at a given temperature is directly proportional to the product of the active masses of the reactants”.
Rate ∝ [Reactants]x
[ ] = \(\frac{\mathrm{n}}{\mathrm{v}}\), {Unit is mol.dm-3 or mol.L-1}
where,
n is the number of moles and
V is the volume of the container (dm3 or L).

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 6.
What is the reaction quotient? Write the relation of K & Q.
Answer:
Reaction quotient ‘Q’ is defined as the ratio of the product of active mass of reaction products raised to the respective stoichiometric coefficients in the balanced chemical equation to that of the reactants under non equilibrium.
Reaction quotient Q.
Q = \(\frac{[\mathrm{C}]^{1}[\mathrm{D}]^{\mathrm{m}}}{[\mathrm{A}]^{\mathrm{x}}[\mathrm{B}]^{\mathrm{y}}}\)
If Q = Kc, the reaction is in equilibrium
If Q > Kc, the reaction will proceed in the reverse direction i.e., formation of reactants.
If Q < Kc, the reaction will proceed in the forward direction i.e., formation of products.

Question 7.
Explain effect of pressure of formation of HI.
Answer:
Pressure has no effect on the equilibrium when the total number of the moles of the gaseous reactants and the gaseous products are equal. ( ∆ng = 0).
Therefore, pressure has effect only on the equilibrium with ∆ng = 0.
Let us consider the following reactions
H2(g) + I2(g) ⇌ 2HI(g)
N2(g) + O2(g) ⇌ 2NO(g)
Here,
The number of moles on reactants and products are equal. So pressure has no effect on them.

Question 8.
The equilibrium concentrations of NH3, N2 and H2 are 1.8 × 10-2 M, 1.2 × 10-2 M and 3 × 10-2 M respectively. Calculate the equilibrium constant for the formation of NH3 from N2 and H2. [Hint: M= mol lit-1]
Solution:
Given data:
[NH3] = 1.8 × 10-2 M ;
[N2] = 1.2 × 10-2 M ;
[H2] = 3 × 10-2 M ;
Kc = ?
N2(g) + 3H2(g) ⇌ 2NH3(g)
Kc = \(\frac{\left[\mathrm{NH}_{3}\right]^{2}}{\left[\mathrm{~N}_{2}\right]\left[\mathrm{H}_{2}\right]^{3}}\)
Kc = \(\frac{1.8 \times 10^{-2} \times 1.8 \times 10^{-2}}{1.2 \times 10^{-2} \times 3 \times 10^{-2} \times 3 \times 10^{-2} \times 3 \times 10^{-2}}\)

Kc = 1 × 10-2 l2 mol-2

Question 9.
One mole of H2 and one mole of I2 are allowed to attain equilibrium. If the equilibrium mixture contains 0.4 mole of HI. Calculate the equilibrium constant.
Answer:
Given data:
[H2] = 1 mole;
[I2] = 1 mole
At equilibrium, [HI] = 0.4 mole; Kc = ?
H2(g) + I2 ⇌ 2HI(g)
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 25

Question 10.
Relate the three equilibrium constants.
i) N2 + O2 ⇌ 2NO; K1
ii) 2NO + O2 ⇌ 2NO2; K2
iii) N2 + 2O2 ⇌ 2NO2; K3
Answer:
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 26

Question 11.
Write the equilibrium constant for the following:
i)H2O2(g) ⇌ H2O + 1/2O2(g)
ii) CO(g) + H2O(g) ⇌ CO2(g) + H2(g)
iii) N2O4(g) ⇌ 2NO2(g)
Answer:
i)H2O2(g) ⇌ H2O + 1/2O2(g)
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 27

ii) CO(g) + H2O(g) ⇌ CO2(g) + H2(g)
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 28

iii) N2O4(g) ⇌ 2NO2(g)
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 29

Question 12.
Calculate the ∆ng, for the following reactions:
i) H2(g) + I2(g) ⇌ 2HI
ii) 2H2O(g) + 2Cl2(g) ⇌ 4HCl(g) + O2(g)
∆ng = (Total number of moles of gaseous products) – (Total number of moles of gaseous reactants)
Answer:
i) H2(g) + I2(g) ⇌ 2HI
∆ng = 2 – 2 = 0
∆ng = 0

ii) 2H2O(g) + 2Cl2(g) ⇌ 4HCl(g) + O2(g)
∆ng = 5 – 4 = 1
∆ng = 1

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 13.
For the reaction A+B ⇌ 3C at 25°C, a 3 litre volume reaction vessel contains 1, 2, and 4 moles of A, B, and C respectively at equilibrium, calculate the equilibrium constant Kc of the reaction at 25°C.
Answer:
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 30

Question 14.
At temperature T1 the equilibrium constant of reaction is K1 At a higher temperature T2, K2 is 10% of K1. Predict whether the equilibrium is endothermic or exothermic.
Answer:
At temperature, T1, the equilibrium constant is K1
At a high temperature, T2, the equilibrium constant K2 = 10%KX
K2 = \(\frac{10}{100}\) K1
K2 = 0.1 K1
K1 > K2
Hence, the equilibrium is exothermic.

Question 15.
Calculate the Kc when a mixture containing 8.07 moles of H2 and 9.08 moles of I2 are reacted at 448°C until 13.38 moles of HI was formed at the equilibrIum.
Answer:
The equilibrium reaction is,
H2(g) + I2(g) ⇌ 2HI(g)
Kc = \(\frac{(2 x)^{2}}{(a-x)(b-x)}\)
a = 8.07 moles;
b = 9.08 moles
2x = 13.38 moles
x = 6.69 moles
Kc = \(\frac{4(6.69)^{2}}{(8.07-6.69)(9.08-6.69)}\)

= \(\frac{4 \times 44.75}{1.38 \times 2.39}\)
Kc = 54.29

Question 16.
For the equilibrium 2NOCl(g) ⇌ 2NO(g) + Cl2(g) the value of the equilibrium constant Kc is 3.75 × 10-6 at 790°C. Calculate Kp for this equilibrium at the same temperature. [Hint: Kp = Kc(RT)∆ng]
Answer:
Kc = 3.75 × 10-6;
T = 790 + 273 = 1063 K
Kp = Kc × (RT)∆ng
For the reaction,
2NOCl(g) ⇌ 2NO(g) + Cl2(g)
∆ng = 3 – 2 = 1
Kp = 3.75 × 10-6 × (8.314 × 1063)
= 33141.6 × 10-6
= 3.31 × 104 × 10-6
Kp = 3.31 × 10-2

Question 17.
How much PCl5 must be added to one litre volume reaction vessel at 250°C in order to obtain a concentration of 0.1 mole of Cl2, Kc for PCl5 ⇌ PCl3 + Cl2 is 0.0414 mol dm-3 at 250°C.
Answer:
PCl5 ⇌ PCl3 + Cl2
Number of moles of PCl5 at equilibrium = a – 0.1
Number of moles PCl3 at equilibrium = 0.1
Number of moles Cl2 at equilibrium = 0.1
Kc = \(\frac{\left[\mathrm{PCl}_{3}\right]\left[\mathrm{Cl}_{2}\right]}{\left[\mathrm{PCl}_{5}\right]}\)
= 0.0414
= \(\frac{0.1 \times 0.1}{a-0.1}\)
0.01 = (a – 0.1) 0.0414
0.01 = 0.0414a – 0.00414
0.0414a = 0.01414
a = 0.3415 mole

Question 18.
At 540 K, the equlllbrium constant Kp for PCl5 dissociation equilibrium at 1.0 atm is 1.77 atm. Calculate equilibrium constant in molar concentration (Kc) at same temperature and pressure.
Answer:
Kp = 1.77 atm;
T = 540 K;
a = 0.082
PCl5 ⇌ PCl3 + Cl2
∆ng = 2 – 1 = 1
Kp = Kc(RT)∆ng
1.77 = Kc × (0.0821 × 450)1
Kc = \(\frac{1.77}{(0.0821 \times 540)}\)
= 4 × 10-2 moles/litres.

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

III. Long question and answers (5 Marks):

Question 1.
Derive the Equilibrium constants Kp and K for the homogeneous reactions.
Answer:
Let us consider a reversible reaction,
xA + yB ⇌ lC + mD
where A and B are the reactants, C and D are the products, and x, y, l, and m are the coefficients of A, B, C, and D respectively.
Applying Law of mass action, the rate of the forward reaction,
rf α [A]x [B]y (or)
rf = kf [A]x [B]y
Similarly, the rate of the backward reaction,
rb a [C]l [D]m (or)
rb = k, [C]l [D]m
where kf and kb are proportionality constants
At equilibrium, Rate of forward reaction(rf) = Rate of backward reaction(rb)
kf α [A]x [B]y = kb a [C]l [D]m (or)
\(\frac{\mathrm{k}_{\mathrm{f}}}{\mathrm{k}_{\mathrm{b}}}=\frac{[\mathrm{C}]^{l}[\mathrm{D}]^{m}}{[\mathrm{~A}]^{x}[\mathrm{~B}]^{y}}\) = Kc
where, Kc is the equilibrium constant in terms of concentration.

At a given temperature, the ratio of the product of active masses of products to that the reactants is a constant, known as equilibrium constant. Each concentration term is raised to the power which is equal to the respective stoichiometric coefficients in the balanced chemical equation. Later when we study chemical kinetics we will learn that this is only approximately true. If the reactants and products behave as gases, then the equilibrium constant in terms of partial pressures can be written as

\(\frac{\mathrm{P}_{\mathrm{C}}^{l} \times \mathrm{P}_{\mathrm{D}}^{m}}{\mathrm{P}_{\mathrm{A}}^{x} \times \mathrm{P}_{\mathrm{B}}^{y}}\)

where, Pc is the partial pressure of the gas, C and so on.

Question 2.
Derive Kp & Kc relation for the formation of HI.
Answer:
Synthesis of HI:
Consider that ‘a’ moles and ‘b’ moles are the initial concentration of H2 and I2 respectively, taken in a container of volume V. Let ‘x’ moles of each of H2 and I2 react together to form 2x moles of HI.
H2(g) + I2(g) ⇌ 2HI(g)
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 31
The equilibrium constant Kp can also be calculated as follows:
Total number of moles at equilibrium = a – x + b – x + 2x = a + b.
If the total pressure of the system at equilibrium be P, then
Partial pressure of H2,
pH2 = \(\left(\frac{a-x}{a+b}\right)\)P

Partial pressure of I2,
pI2 = \(\left(\frac{b-x}{a+b}\right)\)P

Partial pressure of HI,
pHI = \(\left(\frac{2x}{a+b}\right)\)P

Kp = \(\frac{\left(\frac{2 x}{a+b}\right)^{2} \mathrm{P}^{2}}{\left(\frac{a-x}{a+b}\right) \mathrm{P}\left(\frac{b-x}{a+b}\right) \mathrm{P}}=\frac{4 x^{2}}{(a-x)(b-x)}\)
In the above equilibrium, Kc and Kp are thus shown to be equal.

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 3.
Derive the equilibrium constant Kp & Kc for the Dissociation of PCl5.
Answer:
Dissociation of PCl5:
Consider that ‘a’ moles is the initial concentration of PCl5 taken in a container of volume V. Let ‘x’ moles of PCl5 be dissociated into x moles each of PCl3 and Cl2.
PCl5(g) ⇌ PCl3(g) + PCl2(g)
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 32
The equilibrium constant Kp can also be calculated as follows:
Total number of moles at equilibrium = a – x + x + x = a + x
If the total pressure of the system at equilibrium be P, then
Partial pressure of PCl5,
pPCl5 = \(\left(\frac{a-x}{a+x}\right)\)P;

Partial pressure of PCl3,
pPCl3 = \(\left(\frac{x}{a+x}\right)\)P;

Partial pressure of Cl2
pCl2 = \(\left(\frac{x}{a+x}\right)\)P

Kp = \(\frac{\left(\frac{x}{a+x}\right) \mathrm{P}\left(\frac{x}{a+x}\right) \mathrm{P}}{\left(\frac{a-x}{a+x}\right) \mathrm{P}}=\frac{x^{2} \mathrm{P}}{(a-x)(a+x)}\)

Question 4.
Explain the effect of Concentration of formation of HI?
Answer:
Effect of concentration:
At equilibrium, the concentration of the reactants and the products does not change. The addition of more reactants or products to the reacting system at equilibrium causes an increase in their respective concentrations.

According to Le Chatelier’s principle, the effect of increase in concentration of a substance is to shift the equilibrium in a direction that consumes the added substance. Suppose at equilibrium if one of the reactants is added, then the equilibrium will shift in the forward direction and if one of the products is added, then the equilibrium will shift in backward direction.
Let us consider the reaction,
H2(g) + I2(g) ⇌ 2HI(g)

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 33

On addition of H2 or I2 to the equilibrium mixture product HI will tend to increase. In order to minimize the stress, the system shifts the reaction in a direction where H2 and I2 are consumed i.e., the formation of HI would relieve the stress. Hence, the equilibrium shifts to the right (forward direction).

Similarly, removal of HI (product) also boosts the forward reaction and increases the concentration of products.
If HI is added to the equilibrium mixture, the concentration HI is increased, then the system proceeds in the reverse direction to nullify the stress.

Question 5.
The equilibrium constant at 298 K for a reaction is 100. A + B ⇌ C + D. If the initial concentration of all the four species were 1 M each what will be equilibrium concentration of D (in mol lit-1)
Solution:
Given data:
[A] = [B] = [C] = 1 M;
Kc = 100; [D] = ?
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 34
10(1 – x) = 1 + x
10 – 10x – 1 – x = 0
9 – 11x = 0
11x = 9
x = 9/11 = 0.818
So, [D] at equilibrium = 1 + 0.818 = 1.818 M

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 6.
What happens when ∆ng = 0, ∆ng = -ve, ∆ng= +ve In a gaseous reaction?
Answer:
(i) When ∆ng = 0, the total number of moles of gaseous products are equal to the total number of moles of gaseous reactants.
Eg:
H2(g) + I2(g) ⇌ 2HI(g)
∆ng = 2 – 2 = 0
Kp = Kc(RT)∆ng
If ∆ng = 0,
Kp = Kc(RT)0
∴ Kp = Kc

(ii) When ∆ng = +ve, the total number of moles of gaseous products are greater than the total number of moles of gaseous reactants.
Eg:
2H2O + 2Cl2(g) ⇌ 4HCl(g) + O2(g)
∆ng = 5 – 4 = 1
Kp = Kc(RT)1
Kp = Kc(RT)
∴ Kp > Kc

(iii) When ∆ng = -ve, the total number of moles of gaseous products are greater than the total number of moles of gaseous reactants.
N2(g) + 3H2(g) ⇌ 2NH3(g)
∆ng = 2 – 4 = -2
Kp = Kc(RT)-2

Kp = \(\frac{K_{c}}{(R T)^{2}}\)

∴ Kp < Kc

Question 7.
What is the relationship between the dissociation and formation equilibrium constant?
Answer:
In a chemical equilibrium reaction, the equilibrium constant for the dissociation equilibrium reaction which is also known as dissociation constant is found to be the reciprocal value of the equilibrium constant for the formation equilibrium reaction.
Formation of equilibrium reaction,
2SO2(g) + O2 ⇌ 2SO3
Kc = \(\frac{\left[\mathrm{SO}_{3}\right]^{2}}{\left[\mathrm{SO}_{2}\right]^{2}\left[\mathrm{O}_{2}\right]}\) dm3 /mole.

Dissociation equilibrium reaction of SO3 the reactants became products and vice versa.
2SO3(g) ⇌ 2SO2(g) + O2(g)
Kc‘ = \(\frac{\left[\mathrm{SO}_{2}\right]^{2}\left[\mathrm{O}_{2}\right]}{\left[\mathrm{SO}_{3}\right]^{2}}\) mole/dm3
= \(\frac{1}{\mathrm{~K}_{\mathrm{c}}}\)

Kc‘ is considered as the dissociation constant of SO3 gas. Usually, the equilibrium constant of the dissociation equilibrium is the reciprocal of the equilibrium constant of the formation equilibrium reaction.

Question 8.
In the equilibrium H2 + I2 ⇌ 2HI, the number of moles of H2, I2, and HI are 1, 2, 3 moles respectively. Total pressure of the reaction mixture is 60 atm. Calculate the partial pressures of H2, I2, and HI in the mixture.
Solution:
H2 + I2 ⇌ 2HI
Number of moles of H2 at equilibrium = 1 mole
Number of moles of I2 at equilibrium = 2 mole
Number of moles of HI at equilibrium = 3 mole
Total number of moles of equilibrium = 1 + 2 + 3 = 6 moles
Mole fraction of H2 = 1/6;
Mole fraction of I2 = 2/6;
Mole fraction of HI = 3/6
Partial pressure = Mole fraction × Total pressure
PH2 = \(\frac{1}{6}\) × 60 = 10 atm;
PI2 = \(\frac{2}{6}\) × 60 = 20 atm;
PHI = \(\frac{3}{6}\) × 60 = 30 atm.

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 9.
In 1 litre volume reaction vessel, the equilibrium constant K of the reaction PCl5 ⇌ PCl3 + Cl2 is 2 × 10-4 What will be the degree of dissociation assuming only a small extent of 1 mole of PCl5 has dissociated?
Answer:
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 35
since ‘x’ is very small compared to 1,
then K2 = x2
2 × 10-4 = x2
Degree of dissociation x = \(\sqrt{2 \times 10^{-4}}\)
= 1.414 × 10-2

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium

Question 10.
At 35°C, the value of K for the equilibrium reaction N2O4 ⇌ 2NO2 is 0.3174, Calculate the degree of dissociation when P is 0.2382 atm.
Answer:

N2O4 ⇌ 2NO2N2O4NO2
Initial number of moles10
Number of moles dissociatedx2x
Number of moles  equilibrium1 – x2x

Total number of moles at equilibrium = 1 – x + 2x = 1 + x
Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 36

Question 11.
Degree of dissociation of PCl5 at 1 atm and 25°C is 0.2. Calculate the pressure at which PCl5 is half dissociated at 25°C.
Answer:
For PCl5 dissociation equilibrium,
Kp = \(\frac{x^{2} p}{1-x^{2}}\) [ P = total pressure = 1 atm]
x = 0.2
Kp = \(\frac{(0.2)^{2}(1.0)}{1-(0.2)^{2}}\)
= \(\frac{0.04}{1-0.04}\)

Samacheer Kalvi 11th Chemistry Guide Chapter 8 Physical and Chemical Equilibrium 37

Question 12.
Initially, 0.1 moles each of H2 and I2 gases and 0.02 moles of HI gas are mixed in a reaction vessel of constant volume at 300K. Predict the direction towards which the reaction proceeds [K = 3.5 x 10-2].
Answer:
The formation of equilibrium is
H2(g) + I2(g) ⇌ 2HI(g)
Kc = \(\frac{[\mathrm{HI}]_{\mathrm{e}}^{2}}{\left[\mathrm{H}_{2}\right]_{\mathrm{e}}\left[\mathrm{I}_{2}\right]_{\mathrm{e}}}\)
= 3.5 × 10-2 at 300 K.

Under non equilibrium conditions;
Q = \(\frac{[\mathrm{HI}]^{2}}{\left[\mathrm{H}_{2}\right]\left[\mathrm{I}_{2}\right]}\)

= \(\frac{\left(2 \times 10^{-2}\right)^{2}}{0.1 \times 0.1}\)

= 4 × 10-2
Thus Q > Kc.
Therefore, the reaction will proceed initially before attaining the equilibrium in a direction such that the Q value is reduced. That is, concentrations of H2 and I2 should be increases, which is a reverse reaction. The Traction proceeds in the left side of fomiation equilibrium of HI and HI decomposes initially to H2 and I2 until Q = Kc.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Bio Botany Guide Pdf Chapter 15 Plant Growth and Development Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Bio Botany Solutions Chapter 15 Plant Growth and Development

11th Bio Botany Guide Plant Growth and Development Text Book Back Questions and Answers

Part – I.

Question 1.
Select the wrong statement from the following:
(a) Formative phase of the cells retain the capability of cell division.
(b) In elongation phase development of central vacuole takes place.
(c) In maturation phase thickening and differentiation takes place.
(d) In maturation phase, the cells grow further.
Answer:
(d) In maturation phase, the cells grow further.

Question 2.
If the diameter of the pulley is 6 inches, length of pointer is 10 inches and distance travelled by pointer is 5 inches. Calculate the actual growth in length of plant.
a) 3 inches
b) 6 inches
c) 12 inches
d) 30 inches
Answer:
options are wrong, (correct Ans = 1.5 inches)
Solution:
Step I:
Diameter of the Pulley=6 inches
Radius of the pulley \(=\frac{6}{2}\)= 3 inches
Actual growth in length= Distance travailed by pointer x Radius of the pulley Length of the pointer
=\(\frac{5 \times 3}{10}\) =1.5=1.5.
Answer:
1.5 inches

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 3.
In unisexual plants, sex can changed by the application of
a) Ethanol
b) Cytokinins
c) ABA
d) Auxin
Answer:
c) ABA

Question 4.
Select the correctly matched one
A) Humanurine i) Auxin-B
B) Corn gram oil ii) GA3
C) Fungs iii) Abscisic acid II
D) Herring fish sperm iv) Kinetin
E) Unripcrnaizegrains v) AuxinA
F) Young cotton boils vi) Zeatin

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development 1
Answer:
b) A – v, B – i, C – ii, D – iv, E – vi, F – iii

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 5.
Seed dormancy allows the plants to:
(a) overcome unfavorable climatic conditions
(b) develop healthy seeds
(c) reduce viability
(d) prevent deterioration of seeds
Answer:
(a) overcome unfavorable climatic conditions

Question 6.
What are the parameters used to measure growth of plants?
Answer:
Growth in plants can be measured in terms, of

  • Increase in length or girth (roots and stems)
  • Increase in fresh or dry weight
  • Increase in area or volume (fruits and leaves)
  • Increase in a number of cells produced.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 7.
What is plasticity?
Answer:
Plasticity refers to the environmental heterophylly seen in Butter cup plant (Ranunculus). In this aquatic plant, the leaves in the air is normal, where as the leaves submerged underwater are highly thin and hairy highly adapted to do carbon assimilation Developmental heterophlly seen in the juvenile plant leaves of cotton and corianter. Where the young leaves have a different shape from the mature leaves is not considered as plasticity.

Question 8.
Write the physiological effects of Cytokinins.
Answer:

  1. Cytokinin promotes cell division in the presence of auxin (IAA).
  2. Induces cell enlargement associated with IAA and gibberellins
  3. Cytokinin can break the dormancy of certain light-sensitive seeds like tobacco and induces seed germination.
  4. Cytokinin promotes the growth of lateral bud in the presence of apical bud.
  5. Application of cytokinin delays the process of aging by nutrient mobilization. It is known as the Richmond Lang effect.
  6. Cytokinin:
    • increases rate protein synthesis
    • induces the formation of inter-fascicular cambium
    • overcomes apical dominance
    • induces the formation of new leaves, chloroplast and lateral shoots.
  7. Plants accumulate solutes very actively with the help of cytokinins.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 9.
Describe the mechanism of photoperiodic induction of flowering.
Answer:
Mechanism of photoperiodic induction of flowering.

  • The physiological change on flowering due to the relative length of light and darkness (photoperiod) is called Photoperiodism.
  • The photoperiod required to induce flowering is called critical day length. Eg. 12 hours in Maryland Mammoth’s Tobacco Xanthium 15.05 hours.

Photoperiodic induction:

  • An appropriate photoperiod in 24 hours cycle constitutes one inductive cycle. Plants may require one or more inductive cycles for flowering.
  • The phenomenon of conversion of leaf primordia into flower primordia under the influence of suitable inductive cycles is called photoperiodic induction. Example: Xanthium (SDP) -1 inductive cycle and Plantago (LDP) -25 inductive cycles.

Site of photoconductive perception:

  • Leaves are the parts that receive photoperiodic stimulus (PPS), again it is only leaves that synthesize floral hormones and translocate them to the apical tip to promote flowering.
  • This can be demonstrated by experiments conducted in the Cocklebur plant. Which is an SD plant. The nature of flower-producing stimulus has been elusive so far. It is believed by physiologists that a hormone is responsible for it, Chailakyan (1936) named it as Florigen It is not possible to isolate it.
ProcedureObservationInference
1. Take potted plant A and defoliate the plant subject it to SD – a conditionThere is no induction of floweringNo leaf to receive stimulus or induction of flowering
2.  Take potted plant B – and defoliate all, except one leaf subject it to SD – condition.There is the induction of floweringOne leaf is enough to receive stimulus or induction of flowering.
3.  Take potted plant C – and defoliate it and subject it to LD conditionThere is no induction of floweringno leaf to receive stimulus or induction of flowering
4. Take potted plant D and subject all leaves to LD but one leaf to SDThere is the induction of floweringOne leaf is enough to receive an induction in the SD condition

Question 10.
Give a brief account of programmed cell death (PCD).
Answer:
Senescence is controlled by plants’ own genetic program and the death of the plant or plants part consequent to senescence is called Programmed Cell Death. In short senescence of an individual cell is called PCD. The proteolytic enzymes involving PCD in plants are phytases and in animals are caspases. The nutrients and other substrates from senescing cells and tissues are remobilized and reallocated to other parts of the plant that survives.

The protoplasts of developing xylem vessels and tracheids die and disappear at maturity to make them functionally efficient to conduct water for transport. In aquatic plants, aerenchyma is normally formed in different parts of the plant such as roots and stems which enclose large air spaces that are created through PCD. In the development of unisexual flowers, male and female flowers are present in earlier stages, but only one of these two completes its development while the other aborts through PCD.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development 2

Part-II.

11th Bio Botany Guide Plant Growth and Development Additional Important Questions and Answers

I. Choose The Correct Answer

Question 1.
The open form of the growth occurs in:
(a) leaves and flowers
(b) stem and root
(c) leaves and stem
(d) stem and flowers
Answer:
(b) stem and root

Question 2.
An example of a De-Differentiating cell is ………………
a) Tracheary element
b) shoot apex
c) Cork cambium
d) root apex
Answer:
c) Cork cambium

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 3.
Primary growth of the plant is due to the activity of:
(a) phloem parenchyma
(b) phloem meristem
(c) vascular cambium
(d) apical meristem
Answer:
(d) apical meristem

Question 4
Choose the natural Auxin of the following
a) Anti Auxin
b) NAA
c) 2.4.D
d) IndoleAcetic Acid (IAA)
Answer:
d) Indole Acetic Acid (IAA)

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 5.
Thickening and differentiation of cells take place during:
(a) elongation phase
(b) formative phase
(c) maturation phase
(d) flowering phase
Answer:
(c) maturation phase

Question 6.
The hormone present in Coconut milk is
a) Gibberellins
b) Ethylene
c) Cytokinin
d) Auxin
Answer:
c) Cytokinin

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 7.
The total growth of the plant consists of four phases in the following order.
(a) Log phase, lag phase, decelerating phase and maturation phase
(b) Log phase, lag phase, maturation phase and decelerating phase
(c) Lag phase, log phase, maturation phase and decelerating phase
(d) Lag phase, log phase, decelerating phase and maturation phase
Answer:
(d) Lag phase, log phase, decelerating phase and maturation phase

Question 8.
Which of the following Phytóhormone does not occur naturally in plants?
a) 2. 4. D
b) GibberellicAcid
c) 6. Furfuryl amino purine
d) IAA
Answer:
a) 2.4.D

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 9.
Absence of light may lead to the yellowish color in plants and this is called:
(a) venation
(b) etiolation
(c) estivation
(d) vernation
Answer:
(b) etiolation

Question 10.
Apical dominance is caused when Auxin
a) Concentration is more than Cytokinins
b) Concentration is less than Cytokinins
c) and Cytokinin concentration are equal
d) and Cytokinin concentration are fluctuating
Answer:
a) Concentration is more than Cytokinins

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 11.
Indicate a plant growth regulator from the following:
(a) cytocin
(b) cytokinins
(c) acetic acid
(d) methylene
Answer:
(b) cytokinins

Question 12.
Which prevents premature fall of fruit?
a) NAA
b) Ethylene
c) GA3
d) Zeatin
Answer:
a) NAA

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 13.
The activity of synergistic effect involves the activity of:
(a) auxin and gibberellins
(b) auxin and ethylene
(c) ABA and gibberellins
(d) none of the above
Answer:
(a) auxin and gibberellins

Question 14.
The term Auxin was coined by
a) Went
b) Darwin
c) Smith
d) Garner
Answer:
a) Went

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 15.
The term auxin was first coined by:
(a) Charles Darwin
(b) Kogl
(c) F.W. Went
(d) Smith
Answer:
(c) F.W. Went

Question 16.
The term Gibberellin was coined by
a) Went
b) Kurosawa
c) Skoog
d) Yabuta
Answer:
d) Yabuta

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 17.
Indicate a synthetic auxin.
(a) Indole Acetic Acid
(b) Phenyl Acetic Acid
(c) Indole Butyric Acid
(d) Naphthalene Acetic Acid
Answer:
(d) Naphthalene Acetic Acid

Question 18.
The mineral required for the synthesis of IAA is
a) Copper
b) Magnesium
c) Zinc
d) Boron
Answer:
c) Zinc

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 19.
Auxin stimulates:
(a) transpiration
(b) respiration
(c) flowering
(d) none of the above
Answer:
(b) respiration

Question 20.
The most widely occurring Cytokinin in plants is
a) ABA
b) NAA
c) TNT
d) IPA
Answer:
d) IPA

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 21.
Who established the structure of gibberellic acid?
(a) Brain etal
(b) Kurosawa
(c) Cross et al
(d) Yabuta and Sumiki
Answer:
(c) Cross etal

Question 22.
The term Florigen was coined by
a) Maheswari
b) Chailakyan
c) R Gane
d) Richmond Lang
Answer:
b) Chailakyan

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 23.
Cytokinins inducing cell division was first demonstrated by:
(a) Haberlandt
(b) Charles Darwin
(c) Clarke
(d) Hubert
Answer:
(a) Haberlandt

Question 24.
Which of the following is a bioassay for Cytokinins?
a) Chlorophyll preservation test
b) Dwarf maize Assay
c) Seed germination Assay test
d) Neem cotyledon Assay
Answer:
d) Neem cotyledon Assay

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 25.
Indicate correct statements.
(i) Genes are intracellular factors for growth.
(ii) Temperature has no role in the growth of plant.
(iii) Oxygen has a vital role in the growth of plants.
(iv) CIN ratio of soil does not affect the growth of plant.
(a) (i) and (iv)
(b) (ii) and (iv)
(c) (i) and (iii)
(d) (ii) and (iii)
Answer:
(c) (i) and (iii)

Question 26.
Avena curvature test as a BioAssay for
a) Auxins
b) GA3
c) Cytokinin
d) Ethylene
Answer:
a) Auxins

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 27.
The stress phytohormones (Abscisic acid) was first isolated by:
(a) Linn et al
(b) Addicott et al
(c) Edward et al
(d) Stone and Black
Answer:
(b) Addicott et al

Question 28.
The Gibberellins have been commercially exploited for
a) increasing the size of grapefruits
b) inducing rooting in stem cuttings
c) breaking the dormancy in seeds
d) production of disease-resistant varieties
Answer:
c) breaking the dormancy in seeds

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 29.
Pick out the correct statement from the following:
(i) Abscisic acid is found abundantly inside the chloroplast of green cells.
(ii) ABA is a powerful growth promotor.
(iii) ABA is formed from the pentose phosphate pathway.
(iv) ABA has anti-auxin and anti-gibberellin properties.
(a) (i) and (iv)
(b) (i) and (ii)
(c) (ii) and (iii)
(d) (ii) and (iv)
Answer:
(a) (i) and (iv)

Question 30.
Biennials can be induced to flower in the first season itself by treatment with
a) Auxin
b) Kinetin
c) GA
d) ABA
Answer:
c) GA

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 31.
Pea and barley are classified under:
(a) short-day plants
(b) short long day plants
(c) long day plants
(d) long short day plants
Answer:
(c) long day plants

Question 32.
Auxin a was isolated from human urine by
a) F.W. went
b) Charles Darwin
c) Kogl and Haugen Smith
d) Denny
Answer:
c) Kogl and Haugen smith

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 33.
Usually, Xanthiumpensylvanicum will flower under:
(a) long day condition
(b) short long day condition
(c) photo neutral condition
(d) short-day condition
Answer:
(d) short-day condition

Question 34.
The most widely occurring Cytokinin in plants is
a) Indole Acetic Acid (LAA)
b) Indole Butyric Acid (IBA)
c) Pentenyl Adenine (IPA)
d) Naphthalene  Acetic Acid (NAA)
Answer:
c) Pentenyl Adenine (IPA)

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 35.
Who found out the phytochrome in plants?
(a) Butler et al
(b) Michell et al
(c) Boumick et al
(d) Gamers and Allard
Answer:
(a) Butler et al

Question 36.
Scientists, those who are connected with Ethylene
(I) Denny
(II) R. Gane
(III) Kurosawa
(IV) Cocken
Options:
a) (I) (II) & (III)
b) (II) (III) & (IV)
c) (I) (II) & (IV)
d) (I) (III) & (IV)
Answer:
c) (I)(II)& (IV)

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 37.
Pick out the wrong statement from the following:
(a) Vernalization increases the cold resistance of plants
(b) It increases the resistance of plants to fungal disease
(c) Vemalizatiqn increase the vegetative period of the plant
(d) It accelerates the plant breeding
Answer:
(c) Vemalizatiqn increase the vegetative period of the plant

Question 38.
Day-neutral plants are
a) Sugarcane & Coleus
b) Bryophyllum& Night Jasmine
c) Wheat, rice & Oats.
d) Potato, Tomato & Cotton
Answer:
d) Potato, Tomato & Cotton

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 39.
In apple and plum, the method of breaking seed dormancy involves the process of:
(a) impaction
(b) Scarification
(c) exposing to red light
(d) Stratification
Answer:
(d) Stratification

Question 40.
Xanthium (Cocklebur) requires …………….. hours of light to induce flowering,
a) 12
b) 9
c) 15.05
d) 13.05
Answer:
c) 15.05

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 41.
The hormone that cannot be isolated
a) IAA
b) ABA
c) NAA
d) Florigen
Answer:
d) Florigen

Question 42.
The term Photoperiodism was coined by
a) Went
b) Butler
c) Gamer
d) Skoog
Answer:
c) Garner

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 43.
ABA acts as antagonistic to
a) Ethylene
b) Cytokinin
c) Gibberellic acid
d) IAA
Answer:
c) Gibberellic acid

Question 44.
If a short-day plant, flowering is induced by
a) Long nights
b) Photo periods less than 12 hrs
c) Photoperiods shorter than critical value and uninterrupted long night
d) Short photoperiods and interrupted long nights
Answer:
c) Photoperiods shorter than critical value and uninterrupted long night.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 45.
Phytochrome is
a) Reddish phytohormone
b) Bluish biliprotein pigment
c) Photoreceptor of apical bud
d) Unstable pigment molecule
Answer:
b) Bluish biliprotein pigment

Question 46.
The growth & ripening is induced by Ethylene in
a) Tropical fruits
b) Temperate fruits
c) Climacteric fruits
d) Nonclimacteric fruits
Answer:
c) Climacteric fruits

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 47.
The bioassay of ABA was done with
a) Rice
b) Wheat
c) Maize
d) Barley
Answer:
a) Rice

Question 48.
Four types of senescence were recognized by
a) Leopold
b) Gamer
c) Addicott
d) Cocken et al
Answer:
a) Leopold

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 49.
The final stage of senescence is
a) PCD
b) Scarification
c) Yellowing
d) Abscission
Answer:
d) Abscission

Question 50.
Match & Find out the Correct Answer

Column IColumn II
1.  Yabuta&Sumikia) Identified Ethylene
2.  Lethan & Millerb) Isolated Auxin from Human urine
3.  Cockenetalc) Isolated and identified Zeatin
4.  Kogi & Haugen Smithd) Isolated Gibberellin in Crystal form

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development 3
Answer:
b) D C A B

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 51.
Match the following and Find the Correct Answer

I. Auxina) Bolting
II. ABAb) Induces Respiration
III. Gibberellinc) Cell division
IV. Ethylened) Weedicide
V. Cytokinine) Closure of stomata

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development 4
Answer:
b) D E A B C

II. Assertion (A) & Reason (R)

Question 52.
a. Both A & R are true and ‘R’ is the correct explanation of A
b. Both A & R are true but ‘R’ is not the correct explanation of A
c. A is true but R is False
d. Both A and ‘R’ are False
Assertion (A): The shoot Apical meristems are the only source of Auxin synthesis
Reason (R): Dormancy of lateral buds over Apical buds is due to Auxin
Answer:
C. A is true but R is False

Question 53.
Assertion (A): Hormones are also called Growth regulator
Reason (R): Hormones promote or inhibit plant growth
Answer:
A. Both Assertion (A) and Reason (R) are true and Reason is the correct explanation of Assertion.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 54.
Assertion (A): In many land Mammoth flowering occurred at different times at different latitude
Reason (R): Many land Mammoth is a tobacco variety
Answer:
b. Both Assertion (A) and, Reason (R) are true and Reason is not the correct explanation of Assertion.

III. 2 Mark Questions

Question 1.
Define closed form of growth in plants.
Answer:
Leaves, flowers, and fruits are limited in growth or of determinate or closed-form growth.

Question 2.
Compare between Absolute and Relative growth rates
Answer:

Absolute growthRelative growth
An increase in the total growth of two organs measured and compared per unit time is called Absolute growth rateThe growth of the given system per unit time expressed per unit initial parameter is called relative growth rate

Question 3.
Name the phases of growth in ‘S’ shaped growth curve.
Answer:

  • Lag phase
  • Log phase
  • Decelerating phase
  • Maturation phase

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 4.
Mention the phase of growth in plants
Answer:
I. Formative phase
II. Elongation phase
III. Maturation phase

Question 5.
Distinguish between absolute growth rate and relative growth, rate.
Answer:
Absolute growth rate:
An increase in total growth of two organs measured and compared per unit time is called absolute growth rate.

Relative growth rate:
The growth of the given system per unit time expressed per unit initial parameter is called relative growth rate.

Question 6.
What is the Grand period of growth
Answer:
The total period from initial to the final stage of growth is called Grand period of growth.
When plotted against time the growth curve is ‘S’ shaped, (sigma curve) it is also known as Grand Period curie consists of 4 phases

  1. Lag,
  2. Log,
  3. Decelerating,
  4. Maturation.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 7.
What is meant by the dedifferentiation of plant cells?
Answer:
Differentiated cells, after multiplication again lose the ability to divide and mature to perform specific functions. This is called redifferentiation, eg: Secondary xylem and Secondary phloem.

Question 8.
Define Phytohormone.
Answer:
The chemical substances synthesized by plants and thus naturally occuring are known as Phytohormones. Eg. Auxin, Gibberellins.
Recently 2 groups – Brassinosteroids, Polyamines were also known to behave like hormones.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 9.
Mention any two synthetic auxins.
Answer:

  • 2, 4 – Dichloro Phenoxy Acetic Acid (2, 4 – D)
  • 2, 4, 5 – Trichloro Phenoxy Acetic Acid (2, 4, 5 – T)

Question 10.
State 3 characteristic features of phytohormones.
Answer:

  1. They are produced in root tips and stem tips and leaves (do not have specialized cells or organs for secretion)
  2. The transfer of hormones takes place through the conducting system (xylem and phloem)
  3. They are required in trace quantities
  4. They either promote, inhibit or modify growth.

Question 11.
Name the natural auxins present in plants.
Answer:

  • Indole Acetic Acid (IAA)
  • Indole Propionic Acid (IPA)
  • Indole Butyric Acid (IBA)
  • Phenyl Acetic Acid (PAA)

Question 12.
Give the historial significance of Agent Orange
Answer:

  • Mixture of two phenoxy herbicides – 2.4. D and 2.4.5 T together known as Agent orange.
  • This Agent orange, was used by USA in Vietnam war as chemical warfare weapon to defoliate forests in Vietnam.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 13.
Does the trimming of plants in gardens have any scientific explanation?
Answer:

  • Yes, trimming of plants removes apical buds and hence apical dominance is prevented the lateral buds sprout and give a beautiful bushy appearance and aesthetic value.
  • Also in tea estates, this trimming develops more lateral branches and more tea leaves thus it has commercial significance.

Question 14.
Where do you find cytokinin hormone in plants?
Answer:
The distribution of cytokinin in plants is not as wide as those of auxin and gibberellins but found mostly in roots. Cytokinins appear to be translocated through xylem.

Question 15.
What is bolting?
Answer:

  • When treated with Gibberellins the rose the plants (genetic dwarf) exhibit excessive internodal growth.
  • This sudden elongation of a stem followed by flowering is called bolting.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 16.
What is Richmond Lang effect?
Answer:
Application of Cytokinin delays the process of aging by nuitrient mobilization.

Question 17.
Why do you call Abscisic acid (ABA) as stress hormone?
Answer:
It inhibits the shoot growth and promotes growth of root system. This character protect the plants from water stress. Hence, ABA is called as stress hormone.

Question 18.
Define photoperiodism & Critical day length.
Answer:

  • The physiological change on flowering due to relative length of light and darkness (Photoperiod) is called
    Photoperiodism.
  • The photoperiod required to induce flowering is called critical day length Eg.
    • Mary land mammoth (tobacco variety) requires 12 hours of light.
    • Cocklebur required 15.05 hours of light.

Question 19.
Write down the importance of photoperiodism in plants.
Answer:

  • The knowledge of photoperiodism plays an important role in hybridisation experiments.
  • Photoperiodism is an excellent example of physiological pre-conditioning that is using an external factor to induce physiological changes in the plant.

Question 20.
What is the importance of photoperiodism?
Answer:

  • The knowledge of photoperiodism an important role in hybridization experiments.
  • It is an excellent example of physiological preconditioning that is using an external factor to induce physiological changes in the plant.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 21.
What is meant by Epigeal germination?
Answer:
During epigeal germination, cotyledons are pushed out of the soil. This happens due to the elongation of the hypocotyl.
Eg: Castor and Bean.

Question 22.
Define Vernalization.
Answer:

  • It is a process by which many annuals and biennials are induced to flower when subjected to low-temperature exposure.
  • T.d. Lysenko first used the term.

Question 23.
Define the term phytogerontology.
Answer:
The branch of botany which deals with ageing, abscission and senescence is called Phytogerontology.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 24.
Distinguish between Epigeal and Hypogeal germination.
Answer:

EpigealHypogeal
Cotyledons pussed out of the soilCotyledons remain below the soil due to rapid elongation of epicotyls.
Happens due to the elongation of the hypocotyl Eg. Castor & BeanEg. Maize

Question 25.
Define seed dormancy and what are its types.
Answer:
The condition of a seed when it fails to germinate even in suitable environmental condition is called seed dormancy.
There are two types
(I) Innate dormancy (II) Imposed dormancy.

Question 26.
What is Scarification?
Answer:

  • By mechanical and chemical treatments like cutting or chipping of hard tough sed coat and use of organic solvents to remove waxy or fatty compounds are called scarification.
  • It is a method of breaking dormancy of the seeds.

Question 27.
Distinguish between Re differentiation and Devernalization.
Answer:

RedifferentiationDevernalization
Differentiated cells after multiplication again lose the ability to divide and mature to perform specific functions, is called Re differentiation.
Eg. Sec.Xylem & Sec.
Phloem The reversal of the effect of vernalization is called Devemalization.

Question 28.
Define Senescence.
Answer:

  • Ageing or getting old is called senescence.
  • It refers to all collective, progressive and deteriorative processes which ultimately lead to complete loss of organization and function (Eg. leaves turn yellow and fall off from plant).

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 29.
What is impaction in seed dormancy.
Answer:

  • In some seeds water and oxygen are unable to penetrate micropyle due to blockage by cork cells.
  • These seeds are shaken vigorously to remove the plug
  • The process of removing the plug or block is called impactation.

Question 30.
What is called stratification in seed dormancy?
Answer:

  • The break dormancy, some plant seeds have to be exposed to well aerated, moist conditions under low temperature (0°c to 10°c) for weeks to months.
  • This kind of seed dormancy breaking treatment is known as stratification.
  • The stratified soil layers should be given a low-temperature treatment for a certain period so as to induce germination.
  • Eg. the Seeds of Rosaceae plants Apple, Plum, Peach, etc.

Question 31.
What are the 4 types of Senescence?
Answer:
Leopold (1961) explained 4 types they are

  1. Overall senescence
  2. Top senescence
  3. Deciduous senescence
  4. Progressive senescence.

Question 32.
What is the Abscission layer or Abscission Zone?
Answer:
Abscission is marked internally at the place of petiole by a distance zone of few layers of thin-walled cells arranged transversely. This zone is called Abscission Zone, which leads to Abscission of the leaf.

Question 33.
The photoperiodic response will not be possible in a defoliated plant. Give scientific reasons.
Answer:
Yes, a defoliated plant will not respond to photoperiodic change because the hormonal substance responsible for flowering is present in the leaves of the plant.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 34.
What is gas chromatography?
Answer:

  • It is a bioassay technique by which Ethylene can be measured.
  • It helps in the detection of the exact amount of ethylene from different plant tissues like lemon and orange.

Question 35.
Give the occurrence and precursors of Gibberellins and Cytokinins.
Answer:

CharacterGibberellinsCytokinin
OccurrenceProduced by plant parts like an embryo, roots, and young leaves near the tip. Immature seeds are rich in Gibberellins.Formed in root apex shoot apex like Auxin. Also formed in buds & young fruits.
PrecursorFormed by 5C precursor, Iso prenoidunit called Iso Pentenyl Pyrophosphate (IPP) through a number of intermediates primary precursor – Acetate.Derived from purine-Adenine.

IV. 3 Mark Questions

Question 1.
Explain Arithmetic growth rate and Geometric growth rate by diagrams.
Answer:
Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development 6

Question 2.
Explain stages in growth by drawing the sigmoid curve.
Answer:

  • The total period from the initial to the final stage of growth is called the Grand period of growth.
  • The graph that is drawn by taking time and rate of growth is ‘S’ shaped. It is known as a sigmoid curve.

It has 4 stages:

  1. Lag phase
  2. Log phase
  3. Decelerating phase
  4. Maturation phase

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development 7

Question 3.
Mention the internal factors, that affect the growth of plants.
Answer:

  • Genes are intracellular factors for growth.
  • Phytohormones are intracellular factors for growth, eg: auxin, gibberellin, cytokinin.
  • C/N ratio.

Question 4.
Mention the Agricultural role of Auxin.
Answer:

  • Eradicate weeds: Eg. 2.4 D and 2.4.5.7
  • Formation of seedless fruits: (Parthenocarpic fruits) Eg. Synthetic Auxin.
  • Break dormancy.
  • Induction of flowering: In pineapple NAA induce flowering
  • Increase the number of female flowers: Eg. Cucurbita.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 5.
List out the agricultural applications of auxins.
Answer:

  • It is used to eradicate weeds, eg: 2,4 – D and 2,4,5 – T.
  • Synthetic auxins are used in the formation of seedless fruits (Parthenocarpic fruit).
  • It is used to break the dormancy in seeds.
  • Induce flowering in Pineapple by NAA & 2,4 – D.
  • Increase the number of female flowers and fruits in cucurbits.

Question 6.
What are the Precursors of Gibberellins?
Answer:

  • Gibberellins are chemically related to terpenoids (natural rubber, Carotenoids, and steroids) formed by 5-C precursors and an Isoprenoid unit called Iso Pentenyl Pyrophosphate (IPP) through a number of intermediates.
  • The primary precursors are Acetate.

Question 7.
What are the uses of ethylene in agriculture?
Answer:

  • Ethylene normally reduces flowering in plants except in Pineapple and Mango.
  • It increases the number of female flowers and decreases the number of male flowers.
  • Ethylene spray in the cucumber crop produces female flowers and increases the yield.

Question 8.
Explain the mechanism of Vernalization by Hypothesis of hormonal involvement.
Answer:
I. Vernalization: According to Purvis

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development 8

 

 

 

 

II. Devernalization
Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development 9

 

 

Question 9.
What are the practical applications of Vernalization?
Answer:

  • It shortens the vegetative period and induces the plant to flower earlier.
  • It increases the cold resistance of the plants.
  • It increases the resistance of plants to fungal disease.
  • Plant breeding can be accelerated.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 10.
What is meant by the viability of seeds?
Answer:

  • Viable means the living condition of the seed
  • The shelf life of the seed after which it cannot germinate is known as the viable period
  • It varies from plant to plant
Name of the plantViability
1. Oxalis seedsFew days
2.  Lotus seedsMore than 1000 years
3.  Judean Dale palm (Methuselah)More than 2000 years

Question 11.
Differentiate between climacteric and Non-climacteric fruits.
Answer:

Climacteric fruitsNon-Climacteric fruits
1.There is a sharp rise in respiration rate near the end of the development of fruit.
2. The ripening on demand can be induced in these fruits by exposing them to normal air conditioning.
3. Epthan secrete Ethylene continuously about 1 ppm of ethylene Eg. Lemon, Apples, Banana, Mango
These fruits cannot be ripened by exposure to ethylene so-known as non-climacteric fruits.
Eg. Grapes, Watermelon orange.

Question 12.
Differentiate between scarification & Stratification in breaking seed dormacy
Answer:

ScarificationStratification
Mechanical and chemical treatment either by cutting, chipping or use of organic solvents to remove waxy or fatty compounds is called scarification.Rosaceous plants (Apple, Plum Peach, and Cherry) will not germinate until they have been exposed to well derated, moist conditions under low temperature (1°c to 10°c) for weeks to months and this treatment is known as stratification.

Question 13.
Mention the factors causing dormancy of seeds.
Answer:

  • Hard, tough seed coat causes barrier effect as impermeability of water, gas and restriction of the expansion of embryo prevents seed germination.
  • Many species of seeds produce imperfectly developed embryos called rudimentary embryos which promotes dormancy.
  • Lack of specific light requirement leads to seed dormancy.
  • A range of temperatures either higher or lower cause dormancy.
  • The presence of inhibitors like phenolic compounds which inhibits seed germination cause dormancy.

Question 14.
What are the factors that affect senescence?
Answer:

Name of the factorEffect of senescence
ABA & EthyleneAccelerates
Auxin & Cytokinin Nitrogen deficiencyreduces increases
Nitrogen supplyretards
High temperature in vernalized seedsAccelerates
Low temperatureRetards
Water stressAccumulation of ABA leading to senescence

Question 15.
What are the morphological and Anatomical changes due to Abscission?
Answer:

  • Abscission Zone: formed at the base of petiole
  • Greenish grey in colour by rows of 2 to 15 cells thick primary wall and middle lamella
  • The dissolution of by pectinase & Cellulase
  • Formation tyloses – that block conduction of vessels
  • Degradation of chlorophyll – Colour of leaves changes and leaves fall off.
  • After Abscission – Suberization of outer layer of cells by the development of periderm.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 16.
Write down the significance of Abscission.
Answer:
1. Abscission separates dead parts of the plant like old leaves and ripe fruits.
2. Helps in dispersal of fruits and continuing the life cycle.
3. Abscission of leaves (in deciduous plants) helps in water conservation during summer.
4. Helps in vegetative propagation (Shedding of gemmae or plantlets) Eg. Bryophyta.

V. 5 Mark Questions

Question 1.
Describe an experiment to measure the growth of a plant or By lever Auxanometer measure the rate of growth in stem tip.
Answer:
Experiment:
1. Arc auxanometer:
The increase in the length of the stem tip can easily by measured by an arc auxanometer. If consists of a small pulley to the axis of which is attached a long pointer sliding over a graduated arc. A thread one end of which is tied to the stem tip and another and to a weight passes over the pulley tightly. As soon as the stem tip increases in length, the pulley moves and the pointer slide over the graduated arc (Refer Figure) The reading is taken. The acutal increase in the lengthwm stem is then calculated by knowing the length of the pointer and the radius of the pulley. If the radius of the pulley is 4 inches and the length of pointer 20 inches the actual growth is measured as follows:
Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development 10

Actual growth in length\(=\frac{\text { Distance travelled by the pointer radius of the }}{\text { Length of the pointer }}\)
For example, actual growth in length \(=\frac{10 \times 4 \text { inches }}{20 \text { inches }}\) = 2 inches

Question 2.
Explain the physiological effect of Auxin? Add a note on its agricultural applications.
Answer:
Cell elongation:
Promotes cell elongation in stem & Coleoptile

Root growth:
At extremely low concentration – promote root growth, at high concentrations it inhibits elongation of roots, but induce more lateral roots

Apical dominance:
Suppression of growth of lateral buds – by apical bud is known as Apical dominance
Prevents Abscission

Secondary growth:
Promotion of cell division in the cambium, responsible for secondary growth this property is exploited in tissue culture. (Callus foundation)

Respiration Stimulates respiration Induces Vascular differentiation.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 3.
Give the Agricultural application of Auxin.
Answer:
Weedicide
2.4.D & 2.4.5. T – Weedicides to remove weeds

Induce parthenocarpy
Synthetic auxins used to induce parthenocarpy (formation of seedless fruits).

Break dormancy
Used to break seed dormancy.

Induce flowering in Pineapple Eg. NAA & 2.4.D

Induce female flowers (numbers)
Eg. Cucumber.

Question 4.
Explain physiological effects of Gibberellins
Answer:

  • Induction of cell division & cell elongation – Extraordinary stem elongation.
  • Reversal of dwarfism & Bolting – Rosette (genetic dwarfism) plants when treated with Gibberellins exhibit excessive enter nodal growth – This sudden elongation of a stem followed by flowering is called Bolting.
  • Breaks dormancy – in Potato tubers.
  • Biennials flower in the 1 st year – Instead of cold exposure, if biennials treated with Gibberellins flower in the 1st year itself.

Question 5.
Write an essay on the role of ethylene on plant physiology and agriculture.
Answer:
Almost all plant tissues produce ethylene gas in minute quantities.
1. Discovery:
In 1924, Denny found that ethylene stimulates the ripening of lemons. In 1934, R. Gane found that ripe bananas contain abundant ethylene. In 1935, Cocken et al., identified ethylene as a natural plant hormone.

2. Occurrence:
Maximum synthesis occurs during climacteric ripening of fruits and tissues undergoing senescence. It is formed in almost all plant parts like roots, leaves, flowers, fruits and seeds.

3. Transport in plants:
Ethylene can easily diffuse inside the plant through intercellular spaces.

4. Precursor:
It is a derivative of amino acid methionine, linolenic acid and fumaric acid.

5. Bioassay (Gas Chromatography):
Ethylene can be measured by gas chromatography. This technique helps in the detection of exact amount of ethylene from different plant tissues like lemon and orange.

6. Physiological Effects:

  • Ethylene stimulates respiration and ripening in fruits.
  • It stimulates radial growth in sterft and roof and inhibits linear growth.
  • It breaks the dormancy of buds, seeds and storage organs.
  • It stimulates the formation of an abscission zone in leaves, flowers and fruits. This makes the leaves to shed prematurely.
  • Inhibition of stem elongation (shortening the internode).
  • In low concentration, ethylene helps in root initiation.
  • Growth of lateral roots and root hairs. This increases the absorption surface of the plant roots.
  • The growth of fruits is stimulated by ethylene in some plants. It is more marked in climacteric fruits.
  • Ethylene causes epinasty.

7. Agricultural role:

  • Ethylene normally reduces flowering in plants except in Pineapple and Mango.
  • It increases the number of female flowers and decreases the number of male flowers.
  • Ethylene spray in cucumber crops produces female flowers and increases the yield.

Question 6.
Explain the physiological Effects of Cytokinins.
Answer:

  • With IAA – Promotes cell division With IAA & GA – Induces cell enlargement
  • Breaks dormancy of light-sensitive seeds (tobacco) induces seed germination.
  • Promotes growth of lateral
  • buds even in the presence of apical bud.
  • Delays the process of aging by nutrient mobilization known as Richmond Lang effect.
  • Induces rate of protein synthesis.
  • Induces the formation of interfascicular cambium Overcomes apical dominance
  • Induces the formation of new leaves chloroplast and lateral shoots.
  • Induces Accumulation of solutes.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 7.
Write down the physiological effects of Ethylene
Answer:

  • Stimulates respiration and thereby ripening of fruits
  • Stimulates radial growth in stem and root and inhibits linear growth.
  • breaks dormancy of
    1. buds
    2. Seeds
    3. Storage Organs
  • Stimulates abscission 2 one formation in
    1. leaves
    2. flowers
    3. fruits (so leaves shed prematurely)
  • Prevents stem elongation by preventing internodal growth
  • Root growth in low concentration
  • Stimulates growth of lateral roots and root hairs and increase the absorptive surface
  • Ripening of fruits – Increases ripening in climacteric fruits (Mango, banana) etc.
  • It causes epinasty

Question 8.
Describe the methods of breaking the dormancy of seeds in plants.
Answer:
The dormancy of seeds can be broken by different methods. These are:
1. Scarification:
Mechanical and chemical treatments like cutting or chipping of hard tough seed coat and use of organic solvents to remove waxy or fatty compounds are called Scarification.

2. impaction:
in some seeds, water and oxygen are unable to penetrate micropyle due to blockage by cork cells. These seeds are shaken vigorously to remove the plug which is called Impaction.

3. Stratification:
Seeds of rosaceous plants (Apple, Plum, Peach, and Cherry) will not germinate until they have been exposed to well aerated, moist conditions under low temperature (0°C to 10°C) for weeks to months. Such treatment is called Stratification.

4. Alternating temperatures: Germination of some seeds is strongly promoted by alternating daily temperatures. An alternation of low and high temperature improves the germination of seeds.

5. Light:
The dormancy of photoelastic seeds can be broken by exposing them to red light.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 9.
Define photoperiodism – Classify plants based on photoperiodism
Answer:
a. The physiological change on flowering due to the relative length of light and darkness is called photoperiodism.

  • Gamer and Allard (1920) coined the term
  • They studied photoperiodism in Biloxi variety of soybean (Glycine max) and Many land mammoth varieties of tobacco.

b. Depending on photoperiodic responses plants are classified into several types.
1. L.D. Plants (Long Day) The photoperiod required to induce flowering is called critical day length depending on critical day length if it is long (more than 12 hours) and with short nights. Eg. Pea Barley and Oats
Short LD Plants: These are Long day plants but need short day length during the early period of growth for flowering Eg. Wheat, Rye

2. SD Plants: Plants requiring short critical day length for flowering or a long night.
Eg. Tobacco, Cocklebur, Soya, Rice, and Chrysanthemum.
Long SD Plants: Actually SD plants but need long days during the early period of growth for flowering Eg. Some SPS of Bryophyllum & Night Jasmine.

3. Intermediate day plants:
These require a photoperiod between a long day and a short day for flowering Eg. Sugarcane and coleus.

4. Day Neutral plants:
There are a number of plants which can flower in all possible photoperiods, known as photo neutral or hiterterminate plants. Eg. Potato, Rhododendron, Tomato & Cotton.

Question 10.
Describe the role of phytochrome in inducing Flowering
Answer:
Definition:
It is a bluish biliprotein responsible for the perception of light in the photophysiological process, existing in two different forms is mainly involved in flower induction, (i.e) Pr and PFr.

  • Butler et al(1959) named the pigment.
  • It exists in two interconvertible forms
PrPFr
1. red light absorbing form
2. Absorbs red lgiht of wavelength 660 nm
3. Biologically inactive form & stable found in the diffused state in cytoplasm
4. Promotes flowering in SD plants and inhibits flowering LD plants.
1. Far-red light absorbing form
2. Absorbs far-red light of wavelength 730 nm
3. Biologically active and it is unstable Associated with a hydrophobic area of the membrane system
4. Promotes flowering in LD plants and inhibit flowering in SD plants.

Mechanism:
Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development 14
Other functions:
Play a role in seed germination and changes in membrane conformation.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 11.
Write an Essay on Vernalization
Answer:
Definition:

  • Many biennials and perennials are induced to flower by low-temperature exposure (O°c to 5°c) This process is called Vernalization.
  • T.D. Lysenko – Coined the term.

Mechanism of Vernalization:
2 theories explain the mechanism of vernalization.

1. Hypothesis of Phasic development (T.D. Lysenko),
The development of the annual plant has 2 phases.

  1. Thermostate-Vegetatine stage requiring low temperature and suitable moisture.
  2. Photo stage -high temperature needs to synthesize florigen.

2. Hypothesis of hormonal involvement (Purvis 1961)

Vernalization has several steps
Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development 15

The technique of Vernalization:

  • Seeds soaked in water
  • Allowed to germinate at 10°C to 12°C
  • Transferred to low temperature for few days to 30 days (3°C to 5°C).
  • Germinated seeds after the low temp, treatment are allowed to dry & then sown.
  • Quickened flowering than untreated (control seedling)

Devernalization:
The reversal of the effect of vernalization is called Devemalization.

  • Practical Applications:
  • Vernalization shortens the vegetative period and induces the plant to flower earlier
  • It increases cold resistance
  • It increases fungal resistance
  • It accelerates Plant Breeding.

Question 12.
Define Senescence and give its types
Answer:
Definition:
Getting old or Ageing is call d senescence in plants.
It refers to all collective, progressive, and deteriorative processes which ultimately lead to complete loss of organization and function.
Types – 4 types (Leopold -1961)

  1. Overall senescence: When the entire plant gets affected and dies – Eg. Annuals – Wheat & Soybeans, Perennials – Agave & Bamboo
  2. Top senescence: Occur in aerial parts only Eg. Parrennials – Banana and Gladiolus
  3. Deciduous senescence: Occur only in leaves Eg. Decidual plants – Elm and Maple
  4. Progressive Senescence: Occur in Annuals occur in old leaves first followed by new leaves than stem and finally root system.

Samacheer Kalvi 11th Bio Botany Guide Chapter 15 Plant Growth and Development

Question 13.
Explain the physiology of senescence and Factors affecting senescence Physiology of Senescence :
Answer:

  • Change in the structure of cells
  • Vacuoles act like lysosome-secrete hydrolytic enzymes.
  • Reducation in photosynthetic rate (due to loss of chlorophyll & accumulation of anthocyanin)
  • The decrease in Starch content,  Protein content
  • Decrease in …………. r RNA level due to increased activity of enzyme RNA ase
  • Degeneration of DNA – by increased activity of enzyme DNA ase

Factors affecting senescence :

Name of the factorEffect of senescence
ABA & EthyleneAccelerates
Auxin & Cytokinin Nitrogen deficiencyreduces increases
Nitrogen supplyretards
High temperature in vernalized seedsAccelerates
Low temperatureRetards
Water stressAccumulation of ABA leading to senescence

Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Bio Botany Guide Pdf Chapter 14 Respiration Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Bio Botany Solutions Chapter 14 Respiration

11th Bio Botany Guide Respiration Text Book Back Questions and Answers

Part-I.

Question 1.
The number of ATP molecules formed by complete oxidation of one molecule of pyruvic acid is:
(a) 12
(b) 13
(c) 14
(d) 15
Answer:
(a) 12

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 2.
During oxidation of two molecules of cytosolic NADH + H+, number of ATP molecules produced in plants are
a) 3
b) 4
c) 6
d) 8
Answer:
b) 4

Question 3.
The compound which links glycolysis and Krebs cycle is:
(a) succinic acid
(b) pyruvic acid
(c) acetyl CoA
(d) citric acid
Answer:
(c) acetyl CoA

Question 4.
Assertion (A): Oxidative phosphorylation takes place during the electron transport chain in mitochondria.
Reason (R): Succinyl Co A is phosphorylated into succinic acid by substrate phosphorylation.
a) A and R is correct. R is correct explanation of A
b) A and R is correct but R is not the correct explanation of A,
c) A is correct but R is wrong
d) A and R is wrong
Answer:
c) A is correct but R is wrong

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 5.
Which of the following reaction is not involved in Krebs cycle.
(a) Shifting of phosphate from 3C to 2C
(b) Splitting of Fructose 1,6 bisphosphate of into two molecules 3C compounds.
(c) Dephosphorylation from the substrates
(d) All of these
Answer:
(d) All of these

Question 6.
What are enzymes involved in phosphorylation and dephosphorylation reactions in EMP pathway?
Answer:
(i) Enzymes involved in phosphorylation are
a) Hexokinase and phospnofructio kinase.
(ii) Enzymes involved in dephosphorylation are
a) Phosphoglycerate Kinase
b) Pyruvate Kinase

Question 7.
The respiratory quotient is zero in succulent plants. Why?
Answer:
In some succulent plants like Opuntia, Bryophyllum carbohydrates are partially oxidised to organic acid, particularly malic acid without the corresponding release of CO2 but O2 is consumed hence the RQ value will be zero.

Question 8.
Explain the reactions taking place in mitochondrial inner membrane.
Answer:
Electron and hydrogen (proton) transport takes place across four multiprotein complexes (I-IV). They are.
1. Complex-I (NADH dehydrogenase).
It contains a flavoprotein (FMN) and associated with non-heme iron Sulphur protein (Fe-S). This complex is responsible for passing electrons and protons from mitochondrial NADFI (Internal) to Ubiquinone (UQ)
NADH+H+UQ ⇌ NAD+UQH2

2. In plants, an additional NADH dehydrogenase (External) complex is present on the outer surface of inner membrane of mitochondria which can oxidise cytosolic NADH + H+.
Ubiquinone (UQ) or Coenzyme Quinone (CoQ) is a small, lipid-soluble electron, proton carrier located within the inner membrane of mitochondria).

3. Complex-II (succinic dehydrogenase) It contains FAD flavoprotein is associated with non-heme iron Sulphur (Fe-S) protein. This complex receives electrons and protons from succinate in Kerbs cycle and is converted into fumarate and passes to ubiquinone.
Succinate + UQ Fumaraic LQH2

4. Complex-III (Cytochrome bcj complex) This complex oxidises reduced ubiquinone (ubiquinol) and transfers the electrons through Cytochrome bc1 Complex (Iron Sulphur centci bcl complex) to cytochrome c.
Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration 1

5. Complex IV (Cytochrome c oxidase) Complex IV is the terminal oxidase and brings about the reduction of 1/2 O2 to H2O. TWO protons are needed to form a molecule of H2O (terminal oxidation).
Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration 2

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 9.
What is the name of alternate way to glucose breakdown? Explain the process in involved in it?
Answer:

  • Pentose phosphate pathway is the alternate pathway for breakdown of glucose.
  • Pentose phosphate pathway was described by Warburg, Dickens and Lipmami (1938).
  • It is also known as Hexose monophosphate shunt (HMP shunt) or Direct oxidative phase and non – oxidative phase.
  • The oxidative phase convert six molecules of six carbon Glucose 6 phosphate to 6 molecules of five-carbon sugar Ribulose – 5 Phosphate with loss of 6CO2 and generation of 12 NADPH + H+

Non oxidative pathway convert Ribulose – 5 – phosphate molecules to various intermediates such as
Ribose – 5 – phosphate (5C)
Xylulose – 5 – phosphate (5C)
Glyceraldehyde – 3 – phosphate (3C)
Sedoheptulose – 7 – phosphate (7C) and
Erythrose – 4 – phosphate (4C)

Finally five molecules of glucose 6 – phosphate is regenerated
6 x Glucose – 6 – phosphate + 12NADP+ + 6H2O

5 x glucose – 6 – phosphate + 6CO2 + Pi + 12 NADPH + 2H+
The net result of complete oxidation of one glucose – 6 – phosphate yield 6CO2 and 12 NADPH + H+. The oxidative pentose phosphate pathway is controlled by glucose – 6 – phosphate dehydrogenase enzyme which is inhibited by high ratio of NADPH to NADP+.

Question 10.
How will you calculate net products of one sucrose molecule upon complete oxidation during aerobic respiration as per recent view?
Answer:
When the cost of transport of ATPs from the matrix into the cytosol is considered, the number will be 2.5 ATPs for each NADH + H+ and 1.5 ATPs for each FADH2 oxidized during the electron transport system. Therefore, in plant cells net yield of 30 ATP molecules for complete aerobic oxidation of one molecule of glucose. But in those animal cells (showing malate shuttle mechanism) net yield will be 32 ATP molecules. Since the sucrose molecule gives, two molecules of glucose and net ATP in plant cell will be 30 × 2 = 60.
In an animal cell, it will be 32 × 2 = 64.

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Part-II.

11th Bio Botany Guide Respiration Additional Important Questions and Answers

I. Choose The Correct Answer

Question 1.
The term respiration was coined by:
(a) Lamark
(b) Kerb
(c) Pepys
(d) Blackman
Answer:
(c) Pepys

Question 2.
Black man divided respiration into floating respiration and protoplasmic respiration based on respiratory ………..
a) Quotient
b) respiratory reaction
c) respiratory pathway
d) substrate
Answer:
d) substrate

Question 3.
The discovery of ATP was made by:
(a) Lipman
(b) Hans Adolt
(c) Warburg
(d) Karl Lohman
Answer:
(d) Karl Lohman

Question 4.
The type of respiration which is rare and liberates toxic ammonia
a) Protoplasmic respiration
b) floating respiration
c) Aerobic respiration
d) Anaerobic respiration
Answer:
a) Protoplasmic respiration

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 5.
On hydrolysis, one molecule of ATP releases energy of:
(a) 8.2 Kcal
(b) 32.3 kJ
(c) 7.3 Kcal
(d) 7.8 Kcal
Answer:
(c) 7.3 Kcal

Question 6.
To convert Kcal to KJ multiply by 4.18(100 Kcal=418 KJ) calculate the amount KJ energy for 7.3 Kcal
a) 30.6 KJ
b) 32.06 KJ
c) 29.03 KJ
d) 5.01 KJ
Answer:
a) 30.6 KJ

Question 7.
Identify the link reaction:
(a) conversion of glucose into pyruvic acid
(b) conversion of glucose into ethanol
(c) conversion of acetyl CoA into CO2 and water
(d) conversion of pyruvic acid into acetyl coenzyme – A
Answer:
(d) conversion of pyruvic acid into acetyl coenzyme – A

Question 8.
Food materials like carbohydrate, fat and proteins are completely oxidised into CO2, H2O and energy in ………………. respiration
a) anaerobic
b) aerobic
c) Bacterial respiration
d) Facultative
Answer:
b) aerobic

Question 9.
Kreb’s cycle is a:
(a) catabolic pathway
(b) anabolic pathway
(c) amphibolic pathway
(d) hydrolytic pathway
Answer:
(c) amphibolic pathway

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 10.
Which process is occur in yeast and some bacteria and 2 ATP molecules are produced during this process.
a) Anaerobic respiration
b) aerobic respiration
c) mixed fermentation
d) CAC cycle
Answer:
a) Anaerobic respiration

Question 11.
The oxidation of one molecule of NADH + H+ gives rise to:
(a) 2 ATP
(b) 3 ATP
(c) 4 ATP
(d) 2.5 ATP
Answer:
(b) 3 ATP

Question 12.
Net product in Glycolysis are
a) 4ATP and 2NADH + H+
b) 2 ATP and 2NADH + H+
c) 6ATP
d) 24 ATP
Answer:
b) 2ATP and 2NADH + H+

Question 13.
Cyanide acts as electron transport chain inhibitor by preventing:
(a) synthesis of ATP from ADP
(b) flow of electrons from NADH + H+
(c) flow of electrons from cytochrome a3 to O2
(d) oxidative phosphorylation
Answer:
(c) flow of electrons from cytochrome a3 to O2

Question 14.
Which is the raw material for the formation of chlorophylls, cytochrome, phytochrome and pyrrole substance
a) acetyl COA
b) Pyruvic acid
c) Malic acid
d) Succinyl COA
Answer:
d) Succinyl COA

Question 15.
End products of fermentation in yeast is:
(a) pyruvic acid and CO2
(b) lactic acid and CO2
(c) ethyl alcohol and CO2
(d) mixed acid and CO2
Answer:
(c) ethyl alcohol and CO2

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 16.
Which cycle is considered as amphibolic pathway.
a) Calvin cycle
b) Glycolysic
c) ETS chain
d) Kreb cycle
Answer:
d) Kreb cycle

Question 17.
The external factors that affect respiration are:
(a) temperature, insufficient O2 and amount of protoplasm
(b) temperature, insufficient O2 and high concentration of CO2
(c) temperature, high concentration of CO2 and respiratory substrate
(d) temperature, high concentration of CO2 and amount of protoplasm
Answer:
(b) temperature, insufficient O2, and high concentration of CO2

Question 18.
The complex system responsible for passing electrons and protons from mitochondria to ubiquinone is ………………..
a) Complex I
b) Complex II
c) Complex III
d) Complex IV
Answer:
a) Complex I

Question 19.
The oxidative pentose phosphate pathway is controlled by the enzyme:
(a) glucose, 1, 6 diphosphate dehydrogenase
(b) glucose 6 phosphate dehydrogenase
(c) fructose – 6 – phosphate dehydrogenase
(d) none of the above
Answer:
(b) glucose 6 phosphate dehydrogenase

Question 20.
Which are the high energy phosphate groups in ATP
a) adenine
b) Pentose sugar
c) Last two phosphate group
d) First two phosphate group
Answer:
c) Last two phosphate group

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 21.
In-plant tissue erythrose is used for the synthesis of:
(a) Erythromycin
(b) Xanthophyll
(c) Erythrocin
(d) Anthocyanin
Answer:
(d) Anthocyanin

Question 22.
How many ATP molecules are produced when a molecule of glucose undergo fermentation?
a) TwoATPs
b) Six ATPs
c) Eight ATPs
d) one ATP
Answer:
a) Two ATPs

Question 23.
Identify the electron transport inhibitor:
(a) phosphoenol
(b) dinitrophenol
(c) xylene
(d) indol acetic acid
Answer:
(b) dinitrophenol

Question 24.
Enzymatic reaction for partial oxidation of glucose in the absence of oxygen is present in
a) Some Bacteria
b) Yeast fungus
c) A and B
d) Bryophytes
Answer:
c) A and B

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 25.
Cyanide resistant respiration is known to generate heat in thermogenic tissues as high as:
(a) 35° C
(b) 38° C
(c) 40° C
(d) 51° C
Answer:
(d) 51° C

Question 26.
Match the Column I with the enzyme responsible for its production in column II
Answer:

Column IColumn II
A. Citric acid1. Hexose Kinase
B. Glucose 6-Phosphate2. Lactate dehydrogenase
C. Lactic acid3. Pyruvate dehydrogenase
D. Acetvl CO.A4. Citric acid Synthetase

Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration 3

Answer:
a) A-4,B -1,C-2,D-3.

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 27.
Which one is wrongly matched

Column IColumn II
A. NADH +H+Three ATP
B. GlycolysisTwenty four ATP
C. FADTwo ATP
D. Cytoplasmic NADH+H+Two ATP

Answer:
B. Glycolysis – Twenty four ATP

II. 2 Marks Questions

Question 1.
Define respiration?
Answer:
Respiration is a biological process in which oxidation of various food substances like carbohydrates, proteins, and fats take place and as a result of this, energy is produced where O2 is taken in and CO2 is liberated.

Question 2.
Name some High energy compounds present in a cell
Answer:

  • ATP → Adenosine Tri Phosphate
  • GTP → Guanosine Tri Phosphate
  • UTP → Uridine Tri Phosphate

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 3.
What do you understand by compensation of point?
Answer:
The point at which CO2 released in respiration is exactly compensated by CO2 fixed in photosynthesis that means no net gaseous exchange takes place, it is called the compensation point.

Question 4.
What is Anaerobic respiration? What are its steps?
Answer:

  • In the absence of molecular oxygen-glucose is incompletely degraded into either ethyl alcohol (or) Lactic acid.
  • It includes two steps (i) Glycolysis (ii) Fermentation

Question 5.
What is anaerobic respiration?
Answer:
In the absence of molecular oxygen-glucose is incompletely degraded into either ethyl alcohol or lactic acid. It includes two steps:

  1. Glycolysis
  2. Fermentation

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 6.
What is Link reaction?
Answer:
In aerobic respiration, Conversion of Pyruvic acid into acetyl coenzyme – A in the mitochondrial matrix with two molecules of NADH + H+ and 2 CO2. This is called Link reaction (or) transition reaction.

Question 7.
Who is Sir Hans Adolf Krebs?
Answer:
Sir Hans Adolf Krebs was born in Germany on 25th August 1900. He was awarded Nobel Prize for his discovery of Citric acid cycle in Physiology in 1953.

Question 8.
Why Kreb cycle is called as citric acid cycle (or) Tri Carboxylic acid Cycle?
Answer:

  • TCA cycle starts with condensation of acetyl COA with oxaloacetate in the presence of water to yield Citri acid (or) Citrate.
  • So it is also known as citric acid cycle (or) Tricarboxylic acid cycle.

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 9.
Mention the role of NADH dehydrogenase enzyme in the electron transport system.
Answer:
NADH dehydrogenase contains a flavoprotein (FMN) and associated with non – heme iron Sulphur protein (Fe – S). This complex is responsible for passing electrons and protons from mitochondrial NADH (Internal) to Ubiquinone (UQ).

Question 10.
Which cycle is amphibolic pathway? Why? The Krebs cycle is called an amphibolic pathway.
Answer:

  • Kreb cycle is primarily a catabolic pathway Later it is an anabolic pathway too.
  • Hence it is called amphibolic pathway.

Question 11.
Mention any two electron transport chain inhibitors.
Answer:
Two electron transport chain inhibitors:

  1. 2, 4 DNP (Dinitrophenol) – It prevents synthesis of ATP from ADP, as it directs electrons from Co Q to O2.
  2. Cyanide – It prevents flow of electrons from Cytochrome a3 to O2.

Question 12.
How many ATP molecules are produced in aerobic respiration present in plants?
Answer:
In aerobic respiration net gain of 36 ATP molecules produced in complete oxidation of glucose.

Question 13.
What are the significances of Respiratory Quotient?
Answer:
The significances of Respiratory Quotient:

  1. RQ value indicates which type of respiration occurs in living cells, either aerobic or anaerobic.
  2. It also helps to know which type of respiratory substrate is involved.

Question 14.
Who was awarded the Nobel Prize for coupling of oxidation and phosphorylation in mitochondria?
Answer:
Peter Mitchell, a British Biochemist received Nobel Prize for chemistry in 1978.

Question 15.
Mention any two industrial uses of alcoholic fermentation.
Answer:
Two industrial uses of alcoholic fermentation:

  1. In bakeries, it is used for preparing bread, cakes, biscuits.
  2. In beverage industries for preparing wine and alcoholic drinks.

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 16.
Define mixed acid fermentation.
Answer:

  • Formation of Lactic acid, ethanol, formic acid and gases like CO2 and H2 from pyruvic acid.
  • eg. Enterobacteriaceae.

Question 17.
Mention any two internal factors, that affect the rate of respiration in plants.
Answer:
Two internal factors, that affect the rate of respiration in plants:

  1. The amount of protoplasm and its state of activity influence the rate of respiration.
  2. The concentration of respiratory substrate is proportional to the rate of respiration.

Question 18.
Why microorganisms respire an anaerobically?
Answer:

  • Bacteria are prokaryotes and they are devoid of membrane-bound organelle mitochondria.
  • So they are respire anaerobically.

Question 19.
Write down any two significance of the pentose phosphate pathway.
Answer:
Two significance of pentose phosphate pathway:

  1. HMP shunt is associated with the generation of two important products.
  2. Coenzyme NADPH generated is used for reductive biosynthesis and counter damaging the effects of oxygen-free radicals.

Question 20.
Complete the following Picture.
Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration 4
Answer:
A. Compensation point
B. Rate of Respiration

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 21.
Write the missing A and B.
Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration 5
Answer:
A. Ribose
B. Adenine

III. 3 Mark Questions

Question 1.
In the biosphere how do plants and animals are complementary systems, which are integrated to sustain life?
Answer:
In plants, oxygen enters through the stomata and it is transported to cells, where oxygen is utilized for energy production. Plants require carbon dioxide to survive, to produce carbohydrates, and to release oxygen through photosynthesis, these oxygen molecules are inhaled by humans through the nose, which reaches the lungs where oxygen is transported through the blood and it reaches cells. Cellular respiration takes place inside or the cell for obtaining energy.

Question 2.
What is Respiration?
Answer:

  • Breaking of C-C bonds of complex organic compounds through oxidation within the cells.
  • The energy released during respiration is stored in the form of ATP and heat is liberated.
  • It occurs in all the living cells of organisms.

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 3.
What are the factors associated with the compensation point in respiration?
Answer:
The two common factors associated with compensation points are CO2 and light. Based on this there are two types of compensation points. They are the CO2 compensation point and light compensation point. C3 plants have compensation points ranging from 40 – 60 ppm (parts per million) CO2 while those of C4 plants range from 1 – 5 ppm CO2.

Question 4.
Differentiate floating respiration and protoplasmic respiration.
Answer:

Floating respirationProtoplasmic respiration
Carbohydrate (or) fat (or) organic acid serves as a respiratory substrateWhereas protein is a respiratory substrate.
It is a common mode of respiration and does not produce any toxic product.It is rare and liberates toxic ammonia.

Question 5.
What is a redox reaction?
Answer:
NAD+ + 2e + 2H+ → NADH + H+
FAD + 2e + 2H+ → FADH2
When NAD+ (Nicotinamide Adenine Dinucleotide – oxidized form) and FAD (Flavin Adenine Dinucleotide) pick up electrons and one or two hydrogen ions (protons), they get reduced to NADH + H+ and FADH2 respectively. When they drop electrons and hydrogen off they go back to their original form. The reaction in which NAD+ and FAD gain (reduction) or lose (oxidation) electrons are called redox reactions (Oxidation-reduction reactions). These reactions are important in cellular respiration.

Question 6.
Define ETS (or) Electron transport chain (or) What is the importance of ETS and oxidative Phosphorylation in respiration.
Answer:

  • Electron transport chain and oxidative phosphorylation remove hydrogen atoms from the products of glycolysis, link reaction, and Kreb cycle.
  • It releases water molecule with energy in the form of ATP molecules in the mitochondrial inner membrane.

Question 7.
Mention the significance of Kreb’s cycle.
Answer:
The significance of Kreb’s cycle:

  1. TCA cycle is to provide energy in the form of ATP for metabolism in plants.
  2. It provides carbon skeleton or raw material for various anabolic processes.
  3. Many intermediates of the TCA cycle are further metabolised to produce amino acids, proteins, and nucleic acids.
  4. Succinyl CoA is the raw material for the formation of chlorophylls, cytochrome, phytochrome, and other pyrrole substances.
  5. α – ketoglutarate and oxaloacetate undergo reductive amination and produce amino acids.
  6. It acts as a metabolic sink which plays a central role in intermediary metabolism.

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 8.
Write the differences between ubiquinone and Cytochrome C.
Answer:

UbiquinoneCytochrome C
It is a small, lipid-soluble electron, proton carrier located within the inner membrane of mitochondria.It is a small protein attached to the outer surface of inner membrane of mitochondria
It is associated with ETS – complex IIt is associated with ETS – complex IIII

Question 9.
Write down the characteristic of Anaerobic respiration.
Answer:
The characteristic of Anaerobic respiration:

  1. Anaerobic respiration is less efficient than aerobic respiration.
  2. A limited number of ATP molecules is generated per glucose molecule.
  3. It is characterized by the production of CO2 and is used for Carbon fixation in photosynthesis.

Question 10.
RQ will be less than one in Red colour Parts Present in Plants? Why?
Answer:

  • Red colour parts present in plants is due to the presence of anthocyanin
  • Synthesis of anthocyanin require more O2 than CO2 evolved.
  • So RQ will be less than one.

Question 11.
Write down any three external factors, that affect respiration in plants.
Answer:
Three external factors, that affect respiration in plants:

  1. The optimum temperature for respiration is 30°C. At low temperatures and very high temperatures rate of respiration decreases.
  2. When a sufficient amount of O2 is available the rate of aerobic respiration will be optimum and anaerobic respiration is completely stopped. This is called the Extinction point.
  3. The high concentration of CO2 reduces the rate of respiration.

Question 12.
Define Lactic acid fermentation.
Answer:
Formation of Lactic acid from pyruvic acid is Lactic acid fermentation.
Eg. Bacillus bacteria, fungi, muscles of vertebrates.

Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration 6

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 13.
What is the Pentose phosphate pathway?
Answer:

  • It is an alternate pathway for break down of glucose.
  • It takes place in the cytoplasm of mature plant cells.
  • In this pathway glucose 6 phosphate molecule is converted to Ribulose 5 phosphate with CO2 and NADPH + H+.

Question 14.
How alcoholic beverages like beer and wine is made?
Answer:

  • The conversion of pyruvate to ethanol takes place in malted barley and grapes through fermentation.
  • Yeast Carryout this process under anaerobic conditions and this conversion increases ethanol concentration.
  • If the concentration increases It’s toxic effect kills yeast cells and the left out is called beer and wine respectively.

IV. 5 Mark Questions

Question 1.
Ambulate the differences between aerobic and anaerobic respiration.
Answer:

Aerobic respirationAnaerobic respiration
1. It occurs in all living cells of higher organisms.It occurs yeast and some bacteria.
2. It requires oxygen for breaking the respiratory substrateOxygen is not required for breaking the respiratory substrate.
3. The end products are CO2 and H2OThe end products are alcohol and CO2 (or) lactic acid
4. Oxidation of one molecule of glucose produces 36 ATP moleculesOnly 2 ATP molecules are produced.
5. It consists of four stages – glycolysis, link reaction, TCA cycle and electron transport chain.It consists of two stages – glycolysis and fermentation.
6. It occurs in cytoplasm and mitochondriaIt occurs only in cytoplasm

Question 2.
Draw the flow chart diagram For Glycolysis (or) EMP pathway.
Answer:
Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration 7
Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration 8

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 3.
Explain the Pay – off phase of EMP Pathway of Glycolysis (or) Explain the oxidative phase of Glycolysis (or) Triose phase of Glycolysis.
Answer:

  • Two molecules of glyceraldehyde 3 – phosphate oxidatively phosphorylated into two molecules of 1-3
    bisphospho glycerate.
  • During this reaction 2 NAD+ is reduced to 2NADH+ H+ by glyceraldehyde 3-phosphate dehydrogenase.
  • Further reactions are carried out by different enzymes at the end two molecules of pyruvate are produced.
  • In this phase 4 ATPS are produced (at step 7 and step 10)
  • Through Direct transfer of phosphate from substrate molecule to ADP and is converted into ATP is called substrate Phosphotylation. (or) Direct Phosphorylation (or) transphosphorylation.
  • During the reaction (at step 9)2 phospo glycerate dehydrated into phosphoenol pyurvate, a water molecule is removed by the enzyme enolase.
  • As a result enol group is formed within the molecule. This process is called Enolation.

Energy Budge of pay off phase:

  • In the payoff phase totally 4 ATP and 2NADH + H+ molecules are produced.
  • Since 2 ATP molecules are already consumed in the preparatory phase the net products in glycolysis are 2ATP and 2NADH + H+

Question 4.
Explain the preparatory phase of Glycolysis (or) EMP pathway (or) Describe the energonic phase phase of Glycolysis (or) EMP pathway. Describe the hexose phase of Glycolysis (or) EMP pathway.
Answer:
Glycolysis is a linear series of reactions in which 6- carbon glucose split into two molecules of 3 carbon pyruvic acid.
Preparatory phase:

  • Glucose enters glycolysis which is the end product of photosynthesis.
  • Glucose is phosphorylated into glucose 6 phosphate by the enzyme hexokinase and subsequent reactions are carried out by different enzymes.
  • At the end of this phase fructose 1,6 – bisphote is cleaved into glyceraldehyde 3- phosphate and dihydroxyacetone phosphate by the enzyme aldolase.
  • These two are Isomers.
  • Dihydroxyacetone phosphate is isomerised into glyceraldehyde 3- phosphate by the enzyme triose phosphate isomerase.
  • Now two molecules of glyceraldehyde 3 phosphate enter into pay off phase.

During the preparatory phase, two ATP molecules are àonsumed.
Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration 9
Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration 10

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 5.
Explain pyruvate oxidation (or) Link reaction of Glycolysis.
Answer:

  • Two molecules of pyruvate formed by glycolysis in the cytosol enter into mitochondnalrnatrxi.
  • In aerobic respiration this pyruvate with coenzyme A is oxidatively decarboxylated into acetyl CoA by pyruvate dehydrogenase complex. .
  • It produces two molecules of NADH + H+ and 2CO2

It is also called transition reaction (or) Link reaction.
Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration 11
The pyruvate dehydrogenase complex consists of three distinct enzymes.

  1. Pyruvate dehydrogenase
  2. Dihydroiipoyil transacetylase
  3. Dihydrolipoyil dehydrogenase and 5 coenzymes TPP (thymine pyrophosphate)
    • NAD+
    • FAD
    • COA and lipoate.

Question 6.
Draw the flow chart diagram for the Kreb cycle (or) Citric acid cycle.
Answer:
Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration 12

Question 7.
Explain Kreb cycle (or) Citric acid cycle (or) TCA cycle.
Answer:

  • Two molecules of acetyl CoA formed from link reaction now enter into Kreb Cycle.
  • It is named after its discoverer German Biochemist Sir Hans Adolf Kreb (1937).
  • It is takes place in the mitochondrial matrix and inner membrane of mitochondria.
  • The enzymes needed for TCA cycle are found in the mitochondrial matrix except for succinate dehydrogenase which is found in the mitochondrial inner membrane.
  • First step starts with condensation of acetyl CoA with oxaloacetate in the presence of water to yield citric acid (or) citrate.
  • It is followed by the action of different enzymes in cyclic manner.
  • During the conversion of succinyl CoA to succinate by the enzyme succinyl CoA synthetase a molecule of ATP Synthesis from Substrate without entering the electron transport chain is called substrate-level phosphorylation.
  • Kreb Cycle is repeated twice for every glucose molecule.
  • Where two molecules of pyruvic acid produces six molecules of CO2, eight molecules of NADH+H+ two molecules of FADH2 and two molecules of ATP.

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 8.
Significance of Kreb Cycle.
Answer:

  • TCA cycle is to provide energy in the form of ATP for metabolism in plants.
  • It provides carbon skeleton or raw material for various anabolic process.
  • many intermediates of TCA cycle are further metabolised to produce amino acids, proteins and nucleic acids.
  • Succinyl CoA is raw material for formation of chlorophyll, cytochrome, phytochrome and other pyrroles
    substances.
  • α – ketoglutarate and oxaloacetate undergo reductive amination and produce amino acids.
  • it acts as metabolic sink which plays a central role in intermediary metabolism.

Question 9.
Write four Electron transport chain in hibitors.
Answer:

  • 2,4 DNP (Dinitrophenol) – It prevents the synthesis of ATP from ADP, as it directs electrons from CoQ to O2
  • Cyanide – It prevents the flow of electrons from Cytochrome a3 to O2
  • Rotenone – It prevents flow of electrons from NADH + H+ / FADH2 to Co Q
  • Oligomycin – It inhibits oxidative phosphorylation

Question 10.
Tabulate Net Products of ATP gained during aerobic respiration per glucose molecule.
Answer:
Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration 13

Question 11.
Experiment to demonstrate the production of CO2 in aerobic respiration.
Answer:

  • Take small quantity of any seed (groundnut or bean seeds) and allow them to germinate by imbibing them.
  • While they are germinating place them in a conical flask.
  • A small glass tube containing 4 ml of freshly prepared Potassium hydroxide (KOH) solution is hing into the conical flask with the help of a thread and tightly close the one holed cork.
  • Take a bent glass tube, the shorted end of which is inserted into the conical flask through the hole in the cork.
  • The longer end is dipped in a beaker containing water.
  • Observe the position of initial water level in bent glass tube.
  • This experimental setup is kept for two hours.
  • After two hours, the level of water rises in the glass tube. It is because the CO2 evolved during aerobic
    respiration by germinating seeds will be absorbed by KOH solution and the level of water will rise in the glass tube.
  • CO2 + 2KOH → K2CO3 + H2O

Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration 14

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 12.
Compare Alcoholic fermentation.
Answer:

Alcoholic fermentationLactic acid fermentation
1. it produces alcohol and releases CO2 from pyruvic acidIt produces lactic acid and does not release CO2 from pyruvic acid
2. It takes place in two steps.It takes place in single steps.
3. It involves two enzymes, pyruvate decarboxylase with Mg++ and alcohol dehydrogenaseIt uses one enzyme, lactate dehydrogenase with Zn++
4. It forms acetaldehyde as an intermediate compoundDoes not form an intermediate compound.
5. It commonly occurs in yeast.Occurs in bacteria, some fungi, and vertebrate muscles.

Question 13.
Write the Industrial uses of alcoholic fermentation.
Answer:

  • In bakeries, it is used for preparing bread, cakes, biscuits.
  • In beverage industries for preparing wine and alcoholic drinks.
  • In producing vinegar and in tanning, curing of leather.
  • Ethanol is used to make gasohol (a fuel that is used for cars in Brazil).

Question 14.
Tabulate the comparison between glycolysis and fermentation.
Answer:

GlycolysisFermentation
1. Glucose is converted into pyruvic acidStars from pyruvic acid and is converted into alcohol or lactic acid.
2. It takes place in the presence or absence of oxygen.it takes place in the absence of oxygen.
3. Net gain is 2ATP.No net gain of ATP molecules.
4. 2NADH + H+ molecules are produced.2NADH+ H+molecules are utilised
5. It commonly occurs in yeast.Occurs in bacteria, some fungi and vertebrate muscles.

Question 15.
Explain the demonstration of alcoholic fermentation.
Answer:

  • Take a Kuhne’s fermentation tube which consists of an upright glass tube with a side bulb
  • Pour 10% sugar solution mixed with baker’s yeast into the fermentation tube the side tube is filled plug the mouth with lid.
    After some time, the glucose solution will be fermented. The solution will give out an alcoholic smell.
  • The level of the solution in the glass column will fall due to the accumulation of CO2 gas.
  • It is due to the presence of zymase enzyme  yeast which converts the glucose solution into alcohol and CO2
  • Now introduce a pellet of KOH into the tube, the KOH will absorb CO2 and the level of solution will rise in the upright tube.
  • This experiment proves during fermentation CO2 gas is evolved.

Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration 15

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 16.
Write the Factors (Internal and External) which affect the process of respiration.
Answer:
External Factors:

  • The optimum temperature for respiration is 30°C. At low temperatures and very high temperatures rate, respiration decreases.
  • When sufficient amount of O2 is available the rate of aerobic respiration will be optimum and anaerobic respiration  is completely stopped. This is called Extinction point.
  • The high concentration of CO2 reduces the rate of respiration.
  • A plant or tissue transferred from water to salt solution wi li increase the rate of respiration. It is called silt respiration.
  • Light is an indirect factor affecting the rate of respiration.
  • Wounding of plant organs stimulates the rate of respiration in that region.

Internal Factors:

  • The concentration of respiratory substrate is proportional to the rate of respiration
  • The amount of protoplasm and its state of activity influence the rate of respiration.

Question 17.
Write about the alternate pathway for glucose break down (or) Write about pentose phosphate pathway. (or) Phosphogluconate pathway (or) War burg – Dickens Lipmann pathway (or)Hexose Monophosphate pathway (or) HMP Shunt pathway.
Answer:

  • The pentose phosphate pathway was described by Warburg, Dickens, and Lipmann (1938). Hence, it is also called Warburg – Dickens Lipmann pathway.
  • It takes place in the cytoplasm of mature plant cells. It is an alternate way for break4own of glucose.
  • It consists of two phases, oxidative phase, and non-oxidative phase.
  • The oxidative events concert six molecules of six carbon Glucose 6 phosphate to 6 molecules of five-carbon sugar Ribulose -5 phosphate with loss of 12 NADPH + H+ (not NADH).
  • The remaining reactions known as non oxidative pathway, covert Rihulose 5phosphate molecules to various intermediates such as Ribose – 5 – phosphate (5C), Xylulose – 5 – phosphate (5C), Glyceraldehyde – 7 – Phosphate (7C), and Eiythrose -4- phosphate (4C).
  • Finally, five molecules of glucose -6- phosphate is regenerated. The overall reaction is:
    6 x Glucose – 6 – Phosphate + 12NADP+ + 6H2O

    5 x Glucose-6- Phosphate + 6CO2 + Pi + 12NADPH + 12H+
  • The net result of complete oxidation of one glucose-6-phosphate yield 6CO2 and12NADPH+H+

Samacheer Kalvi 11th Bio Botany Guide Chapter 13 Photosynthesis

Question 18.
Draw the cycle for pentsoe phosphate pathway (or) Draw the flow chart for HMP Shunt.
Answer:
Samacheer Kalvi 11th Bio Botany Guide Chapter 14 Respiration 16

Question 19.
Write about the Significance of Pentose Phosphate pathway.
Answer:

  • HMP shunt is associated with the generation of two important products. NADPH and pentsoe sugars, which play a vital role in anaholic reactions.
  • Coenzyme NADPH generated is used by reductive bisynthesìs and counter damaging the effects of oxygen-free radicals.
  • Ribose – 5 – phosphate and its derivatives are used in the synthesis of DNA, RNA, ATP, NAD, FAD and
    Coenzynie A. .
  • Erythrose is used for the synthesis of anthocyanin Jignin and other aromatic compounds.