Category: Important Questions

Students get through the TN Board 12th Bio Botany Important Questions Chapter 10 Economically Useful Plants and Entrepreneurial Botany which is useful for their exam preparation.

TN State Board 12th Bio Botany Important Questions Chapter 10 Economically Useful Plants and Entrepreneurial Botany

Very short answer questions

Question 1.
What is meant by pseudo-cereal?
Answer:
Pseudo cereal refers to the foods that are prepared and eaten as a whole grain but are from grasses. Eg. Quinoa.

Question 2.
Give the scientific names of two bowls of cereal.
Answer:

1. Paddy – Oryza sativa
2. Wheat – Triticum aestivum

Question 3.
Mention any two examples of minor millets.
Answer:

1. Foxtail millet – Setaria italica.
2. Kodo millet – Paspalum scorbiculatum.

Question 4.
Define Pulses.
Answer:
Pulses are the edible seeds that are harvested from the fruits of the Fabaceae family. They ‘provide a vital source of plant-based protein, vitamins, and minerals.

Question 5.
Mention the nativity of black gram and green gram.
Answer:

1. Black gram – India
2. Green gram – India.

Question 6.
Define sugar.
Answer:
Sugar refers to the generic name of sweet tasting soluble carbohydrate that is used in foods and beverages.

Question 7.
Mention any two uses of Palmyra.
Answer:

1. Palm sugar is prepared from the exudate from the inflorescence of Palmyra.
2. Germinated seeds have elongated embryos surrounded by fleshy scale leaf, which is edible.

Question 8.
Explain briefly the property of coffee.
Answer:
Coffee, a non-alcoholic beverage, contains an alkaloid that stimulates the central nervous system. It also possess milS diuretic property.

Question 9.
What is the queen of spices? Write the areas of its cultivation in India.
Answer:
The queen of spices is cardamom. It is cultivated in the Western Ghats and North-Eastern India.

Question 10.
What is meant by red pepper?
Answer:
The red pepper is otherwise called as chilies and used in the preparation of sauces, curry powder, and pickles. The active ingredient is capsaicin.

Question 11.
Mention any two properties of teak wood.
Answer:

1. The heartwood of teak is golden yellow to golden brown in color and changes into darker when exposed to light.
2. It is durable, as it is resistant to the attack of termites and fungi.

Question 12.
Who invented paper production?
Answer:
Paper production is a Chinese invention. They prepared paper from the inner bark of paper mulberry in 105 A.D.

Question 13.
What is folk medicine?
Answer:
Folk medicine refers to the system of medicine practiced by ethnic communities through oral communication without any written documents.

Question 14.
Name any two medicinal plants.
Answer:

1. Keezhanelli – Phyllanthus amarus
2. Nilavembu – Andrographis paniculata.

Question 15.
Define Entrepreneurial Botany.
Answer:
Entrepreneurial Botany is defined as the study of how new businesses are created using plant resources. Eg. the Timber industry, the Rubber industry, etc.

Short answer questions

Question 1.
Mention the uses of wheat.
Answer:

1. In the Northern part of India Wheat is the staple food.
2. Bread and other bakery products are produced from wheat flour.
3. Alcoholic beverages and nutritive drinks are made from malted wheat.

Question 2.
Distinguish between a black gram and green gram.
Answer:

Black gram	Green gram
The outer coat is black in colour.	The outer coat is green in colour.
The botanical name is Vigna mungo	The Botanical name is Vigna radiate.
Uttar Pradesh, Chaattisgarh and Karnataka are major states of cultivation.	Madhya Pradesh, Karnataka and Tamil Nadu are the major states of Cultivation.

Question 3.
What are the national fruits of India? Explain its varieties and uses.
Answer:
The national fruit of India is mango.
The major varieties of mango in India are Alphonsa, Banganapalli, Neelam, and Malkova.
Mango is rich in beta carotenes and forms major table fruit in India. Unripe mangoes are used in chutneys, pickles, side dishes, or maybe eaten raw with salt and chili. Jelly is made from mango pulp. The aerated or non-aerated soft drinks are produced from mango pulp.

Question 4.
Mention the origin and area of cultivation of sugar cane.
Answer:
Sugar cane, Saccharum officinarum is originated from New Guinea.
All districts of Tamil Nadu except Kanyakumari and Nilgiris cultivate sugar cane.

Question 5.
Write down the importance of groundnut.
Answer:
Brazil is the native of groundnut. The nuts contain 45% oil. Kernels are a rich source of phosphorous and vitamins.
It gives the premium cooking oil as it does not smoke. This oil is used in the manufacture of soaps and lubricants.

Question 6.
What is the king of spices? Mention its uses.
Answer:
The king of spices is black pepper, which is otherwise known as “Black Gold of India”. In the preparation of sauces, soups, curry powder, and pickles, it is used as a flavoring agent. It is also used in medicine as an aromatic stimulant for enhancing salivary and gastric secretions. Pepper enhances the bio-absorption of medicines.

Question 7.
List the various uses of rubber.
Answer:

1. 70% of the rubber is being consumed by tire and other automobile manufacturing companies.
2. Rubber is used in the manufacture of footwear, wire and cable insulations, raincoats, household and hospital goods, erasers, adhesives, and rubber bands. Concentrated latex is used for making gloves, balloons, and condoms. Cushion, pillows, and life belts are manufactured from foamed latex.

Question 8.
What is a psychoactive drug? Explain any one of such drugs.
Answer:
Psychoactive drug refers to a drug from some plants, which alters an individual’s perceptions of mind by producing hallucination.
One of the examples is cannabis or marijuana, the botanical name being Cannabis sativa. Marijuana is native of China and now it is legally cultivated in the states of Gujarat, Himachal Pradesh, Uttarkhand, Uttar Pradesh, and Madhya Pradesh of India as industrial hemp. The active principle, which possesses medicinal properties is trans- tetrahydro cannabinol (THC).

Long answer questions

Question 1.
Write down the attributes of cereals as food plants?
Answer:

1. Their greater adaptability and successful colonization on every type of habitat.
2. The relative ease of cultivation is another important quality of cereals.
3. They produce a higher yield per unit area due to their tillering property.
4. The grains can be easily handled because the grains are dry and compact. They can easily be transported and stored without spoilage.
5. They provide energy to the consumer due to their high calorific value.

Question 2.
Write about the importance of vegetables with examples.
Answer:
Vegetables are an important part of healthy eating. They provide many nutrients, including vitamins, potassium, fiber and folic acid. Vitamins A, E and C are abundant is vegetables.
One of the examples of a vegetable is okra, Abelmoschus esculantus. It is otherwise known as Lady’s finger, which is a native of tropical Africa. Lady’s finger is grown in Assam, Maharashtra, and Gujarat in large quantities. In Tamil Nadu, Coimbatore, Dharmapuri, and Vellore are the major districts, which cultivate okra.
The fresh and tender fruits are used as vegetables. It has the most important nutrients, especially phosphorous.

Question 3.
List out the uses of red chilies.
Answer:

1. Red chilies are crushed and powdered to use as condiments.
2. Chilies are used in the manufacture of sauces, curry powders, and preparation of pickles.
3. The active ingredient of chilies is capsaicin.
4. It has pain-relieving properties and used in pain-relieving balms.
5. Chillies are a good source of vitamins C, A, and E.

Question 4.
Write about the folk system of medicine.
Answer:
The rural communities of India are practicing this system of medicine through oral tradition without any authenticated written documents. Ministry of Environment and Forestry launched a program of All India Coordinated Research project on ethnobotany to document the plants used as medicine by ethenic groups in India. About 8000 plant species have been documented as the result of this project.
Irulas, Malayalis, Kurumbas, Paliyans, and Kannis are the tribal groups in Tamil Nadu, who are known for their medicinal knowledge. Some of the important medicinal plants they use include keezhanelli and nilavembu, which are now brought for medicinal use.

Choose the correct answers.

1. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)
(c) (p)-(ni); (q)-(iv); (r)-(i); (s)-(ii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(b) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)

2. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

3. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(b) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
Answer:
(a) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)

4. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(d) (p)-(ii); (q)-(i); fr)-(iv); (s)-(iii)
Answer:
(d) (p)-(ii); (q)-(i); fr)-(iv); (s)-(iii)

5. Which one is called as holy basil?
(a) Phyllanthus emblica
(b) Acalypha indica
(c) Ocimum sanctum
(d) Aegle marmelos
Answer:
(c) Ocimum sanctum

6. Marijuana is included under the family:
(a) Solanaceae
(b) Cannabiaceae
(c) Acanthaceae
(d) Euphorbiaceae
Answer:
(b) Cannabiaceae

7. Which of the following is used as Bio-pest repellent:
(a) Azadirachata indica
(b) Acalypha indica
(c) Vinca rosea
(d) Aegle marmelos
Answer:
(a) Azadirachata indica

8. Chenopodium quinoa is coming under:
(a) Pulses
(b) Cereals
(c) Nuts
(d) Pseudo-cereals
Answer:
(d) Pseudo-cereals

9. Choose the odd man out:
(a) Black gram
(b) Sorghum
(c) Pigeon gram
(d) Green gram
Answer:
(b) Sorghum

10. Choose the odd one:
(a) Coffea arabica
(b) Elettaria cardamomum
(c) Piper nigrum
(d) Cumcuma longa
Answer:
(a) Coffea arabica

11. Find out the odd one.
(a) Phyllanthin
(b) Azadictin
(c) Gibberillin
(d) Morphine
Answer:
(c) Gibberillin

12. Indicate the odd one.
(a) Nilavembu
(b) Garlic
(c) Indian gooseberry
(d) Vilvum
Answer:
(b) Garlic

13. Choose the correct one.

Answer:
(c)

14. Which of the following is not a correct pair?

Answer:
(d)

15. Which of the following is the correct pair?

Answer:
(b)

16. Choose the incorrect pair.

Answer:
(c)

17. Assertion: Phyllanthus is a well-known hepato protective plant used for the treatment of jaundice.
Reason: It has been scientifically proved that the extract of Pamarus is effective against hepatitis B virus.
(a) Both Assertion and Reason are correct, Assertion is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Assertion is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is correct.
(d) Assertion is correct, Reason is not correct.
(e) Both Assertion and Reason are not correct.
Answer:
(b) Both Assertion and Reason are correct, Assertion is not the correct explanation of Assertion.

18. Assertion: Medicinal plants play a significant role in providing healthcare services to urban people.
Reason: They serve as the therapeutic agents as well as important raw material for ’ the manufacture of traditional and modern medicines.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is correct.
(d) Assertion is correct, Reason is not correct.
(e) Both Assertion and Reason are not correct.
Answer:
(c) Assertion is not correct, Reason is correct.

19. Assertion: The essential oil from Jasmine is used in modern perfumery and cosmetics.
Reason: The aroma of Jasmine blends well with other perfumes.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is correct.
(d) Assertion is correct, Reason is not correct.
(e) Both Assertion and Reason are not correct.
Answer:
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.

20. Assertion: An orange dye “Henna” is obtained from the roots of Law Sonia inermis.
Reason: The principal colouring matter lacosone obtained from the root is harmless.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is correct.
(d) Assertion is correct, Reason is not correct.
(e) Both Assertion and Reason are not correct.
Answer:
(e) Both Assertion and Reason are not correct.

21. Which of the following statement is not correct?
(a) Traditionally turmeric is used as skin care cosmetics in Tamil Nadu.
(b) Aloe vera is an antioxidant.
(c) Perfumes are manufactured from essential oil.
(d) All the above statement are not correct.
Answer:
(d) All the above statement are not correct.

22. Choose the correct statement.
(a) Black pepper is known as the queen of spices.
(b) Cardamom is called as the king of spices.
(c) Black pepper is called as the ‘black gold of India’.
(d) None of the above.
Answer:
(c) Black pepper is called as the ‘black gold of India’.

23. Indicate the incorrect statement.
(a) The origin of red mango is Southern Asia
(b) The origin of red gram is Southern Irtdia.
(c) Lady’s finger is a native of Tropical Africa.
(d) Kodo millet is originated from Asia.
Answer:
(d) Kodo millet is originated from Asia.

24. Identify the correct statement.
(a) Rice is the chief source of carbohydrate.
(b) Wheat is the chief sources of protein.
(c) Edible oil is extracted from the husks of paddy.
(d) Rice bran is used as a fuel.
Answer:
(a) Rice is the chief source of carbohydrate.

Students get through the TN Board 12th Bio Botany Important Questions Chapter 9 Plant Breeding which is useful for their exam preparation.

TN State Board 12th Bio Botany Important Questions Chapter 9 Plant Breeding

Very short answer questions

Question 1.
Define organic farming.
Answer:
Organic fanning is defined as an alternative agriculture system, that sustains the health of soils, ecosystem and people, using natural inputs like organic manure, bio-pesticides etc.

Question 2.
Mention any two advantage of biofertilizers.
Answer:

1. Biofertilizers are eco-friendly organic agro-inputs.
2. They are more efficient and cost-effective than chemical fertilizers.

Question 3.
Name any two free-living nitrogen-fixing bacteria:
Answer:

1. Azotobactor
2. Clostridium

Question 4.
What is the importance of root nodule?
Answer:
The root nodules are the place, where the nitrogen-fixing symbiotic bacteria, Rhizobium resides and converts the atmospheric nitrogen into a bioavailable form to the plants.

Question 5.
Define Arbuscular Mycorrhizae.
Answer:
Arbuscular mycorrhizae (AM) is defined as the symbiotic association between certain phycomycetous fungi and angiosperm roots.

Question 6.
Explain Bio-pesticides.
Answer:
Bio-pesticides are biologically based agents j used for the control of plant pests.

Question 7.
Name any two green manure crops.
Answer:

1. Crotalaria juncea
2. Indigofera tinctoria

Question 8.
Define plant breeding.
Answer:
Plant breeding refers to the science of improvement of crop varieties with a higher yield, better quality, resistance to diseases and shorter duration for yield.

Question 9.
Define Mutagenesis.
Answer:
Mutagenesis is defined as the process by which developing new genetic diversity by exposing crop plants to chemical agents or radiation.

Question 10.
Explain hybridization.
Answer:
Hybridization refers to the method of producing new crop varieties, in which two or more plants of varying genetic constitution 1 are crossed to produce a hybrid.

Question 11.
Define Pseudoheterosis.
Answer:
Pseudoheterosis is defined as a hybrid I possessing superiority over parents in vegetative growth, but not in yield and adaptation, usually sterile or poorly fertile.

Question 12.
What are polyploids?
Answer:
Polyploids are plants that possess more than two sets of chromosomes.

Question 13.
Define green revolution.
Answer:
The green revolution is defined as the cumulative result of a series of research, development, innovation and technology transfer initiatives j in order to increase crop production.

Question 14.
Explain Biofortification.
Answer:
Biofortification is referred to as a process by which crops with high levels of vitamins and minerals or high protein and healthier fats are produced.

Question 15.
Mention any two methods of New Plant Breeding Techniques (NBT).
Answer:
The two methods of New Plants Breeding Techniques are:

1. Genetic Engineering
2. Plants tissue culture

Short answer questions

Question 1.
Explain organic agriculture.
Answer:
An alternative type of agriculture in which the agro-inputs are natural and ecofriendly is known as agro farming. It is originated early in the twentieth century. It is an agricultural production system that sustains the health of the soils, ecosystems and people. It relies on natural ecological processes, biodiversity and cycles adapted to local conditions rather than the use of inputs with adverse effect.

Question 2.
What are the characteristics of biofertilizers?
Answer:

1. The biofertilizers are the preparations of living cells or latent cells of microorganisms.
2. They should help the plants uptake of nutrients by their interactions. Eg: Mycorrhiza.
3. Biofertilizers are eco-friendly, cost-effective and more efficient than chemical fertilizers.

Question 3.
What are the advantages of Arbuscular mycorrhizae (AM)?
Answer:

1. Arbuscular mycorrhizae are the process of the symbiotic association between phycomycetous fungi and angiosperm roots.
2. They have the ability to mobilise the phosphate found in the soil abundantly.
3. They also provide the necessary strength to resist diseases, germs and unfavourable weather conditions.

Question 4.
Distinguish between Mass selection and Pureline selection.
Answer:

Mass selection	Pureline selection
Bulk of phenotypically similar plants are selected.	Single plant’s offsprings are selected.
They are heterogeneous cultivers.	Different purelines of cultivers are segregated.
They are registered and marketed.	They are homogenous cultivers.

Question 5.
Who coined the term mutation breeding? Write its advantages.
Answer:
The term “Mutation breeding” was coined by Muller and Stadler in 1927-28.
They have the advantage of improving the defect without losing an agronomic and quality character in agriculture and crop improvement. Gene mutations provide essential inputs for evolution as well as for recombination and selection. Seedless crops are developed by this method.

Question 6.
What are vegetables fortified with nutrients released by the Agricultural Research Institute?
Answer:

1. Vitamin A enriched carrot, spinach, pumpkin.
2. Vitamin C enriched bitter guard, bathua, mustard and tomato.
3. Iron and calcium-enriched spinach and bathura.
4. Protein-enriched beans, broad beans, lablab, French and garden peas.

Question 7.
List the plant’s resistance to insect pests developed through plant breeding.
Answer:

Crop	Variety	Insect pest
Brassica (Rapeseed mustard)	Pusa Gaurav	Aphids
Flat bean	Pusa sem2, pusa sem3	Jassids, aphids and fruit borer
Okra (Bhindi)	Pusasawani pusa A-4	Shoot and Fruit borer

Long answer questions

Question 1.
Write about polyploids breeding.
Answer:
Polyploids are plants, that possess more than two sets of chromosomes. Diploids (2n) number of chromosomes are present in the majority of flowering plants. Polyploids often exhibit increased hybrid vigour by increasing heterozygosity Polyploidy increase the tolerance to both biotic and abiotic stresses. It offers a buffering effect of deleterious mutations. The production of seedless varieties is possible due to meiotic error, Polyploidy often results in reduced fertility and is considered to be a major force in the evolution of both wild and cultivated plants.
Autopolyploidy and Allopolyploids are the two types of polyploids.
Autopolyploidy: The doubling of the chromosome by themselves in the same plant is called autopolyploidy.
Eg: Triploid condition in sugar beets, apple and pear. In tomato, it leads to seedless variety. Polyploidy can be induced by a chemical called colchicine.
Allopolyploids: The multiplication of chromosome sets that are initially derived from two different species, is called allopolyploidy.
Eg: Triticale (Triticum durum X Secale cereal), Raphanobrassica (Brassica oleraceae X Raphanus satious).

Question 2.
List out the objectives of plant breeding.
Answer:
The followings are the objectives of plant breeding.

1. The increase in crop yield, plant vigour and increase in the fertility of the plant are the main objectives of plant breeding.
2. Raise plants with increased tolerance to environmental factors like salinity, temperature and drought.
3. To prevent the premature falling of buds, fruits etc.
4. The synchronous maturity of gametes should be improved.
5. To develop plants that develop resistance to pathogens and pests.
6. To develop photosensitive and thermosensitive varieties of plants

Question 3.
What are the changes that take place in a plant species due to domestication?
Answer:

1. They have to adapt to a greater diversity of environments and a wider geographical range.
2. They may have simultaneous uniform flowering and Suiting.
3. Lack of shattering or scattering of seeds.
4. They may have increased the size of fruits and seeds.
5. They have to change from a perennial to an annual habit.
6. Change in the breeding system.
7. They may change to increased yield.
8. Increased resistance to disease and pest.
9. Parthenocarpic seedless fruits may be developed.
10. Enhancing colour, appearance palatability and nutritional composition.

Question 4.
Draw the diagram showing the benefits of Am colonization and label.
Answer:

Question 5.
Liquid seawater fertilizer is not only organic but also eco-friendly. Justify.
Answer:
Seaweed liquid fertilizer (SLF) contains organic nutrients, like cytokinin, gibberellins and auxin. It also contains macro and micronutrients. Seaweed liquid fertilizer is made from kelp (brown algae), which contains alginate. This alginate reacts with metals in the soil and forms long, cross-linked polymers, which improve the crumbling of soil, swell up when they get wet. It retains moisture for a long time. They are especially useful in organic gardening, which provides carbohydrate for plants.
This manure has more than 70 minerals, vitamins and enzymes which promote vigorous growth in plants. The plants grown in seaweed liquid fertilizer have improved resistance to frost and disease, indicating that this fertilizer is ecofriendly-pesticide.

Choose the correct answer.

1. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(c) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

2. Match the following (Vavilov’s centres):

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(d) (p)-(ii); (q)-(i); (r)-(iv);(s)-(iii)
Answer:
(c) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

3. Match the following:

(a) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(b) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(c) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(d) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
Answer:
(a) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)

4. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(b) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
Answer:
(a) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)

5. The method of creation of genetic variation includes:
(a) Mutation
(b) Hybridization
(c) Vegetative propagation
(d) Tissue culture
Answer:
(c) Vegetative propagation

6. Objective of plant breeding is:
(a) to increase yield
(b) to decrease tolerance to disease
(c) to increase sensitivity toi salinity
(d) to prevent synchronous maturity.
Answer:
(a) to increase yield

7. The introduction of foreign genes into DNA of a plant for the first time in the year:
(a) 1940
(b) 1985
(c) 1994
(d) 2000
Answer:
(c) 1994

8. Bacterial blight resistance was achieved in;
(a) Wheat
(b) Cowpea
(c) Chilli
(d) Cauliflower
Answer:
(b) Cowpea

9. Choose the odd man out.
(a) E.Borlaug
(b) M.S.Swaminathan
(c) Nel jayaraman
(d) N.G.P.Rao
Answer:
(c) Nel jayaraman

10. Find out the odd one out.
(a) Mutation
(b) Gene transfer
(c) Cytoplasmic fusion
(d) Polyploidy
Answer:
(c) Cytoplasmic fusion

11. Indicate the odd one out (Bio fortification)
(a) Protein content
(b) Fat content
(c) Vitamin content
(d) Gibberellin content
Answer:
(d) Gibberellin content

12. Choose the odd one out (NBT)
(a) Plant tissue culture
(b) Genetic Engineering
(c) Heterosis
(d) Somatic hybridization
Answer:
(c) Heterosis

13. Choose the correct pair.

Answer:
(a)

14. Choose the incorrect pair.

Answer:
(b)

15. Choose the correct pair.

Answer:
(b)

16. Choose the incorrect pair.

Answer:
(c)

17. Assertion: Organic agriculture is a production system that sustains the health of the soils, ecosystem and people.
Reason: Organic agriculture relies on ecological processes, biodiversity and cycles adapted to local conditions rather than the use of inputs with adverse effect.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is not correct.
(d) Assertion is not correct, Reason is correct.
(e) Both Assertion and Reason are not correct.
Answer:
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.

18. Assertion: Biofertilizers are eco-friendly agro-inputs.
Reason: They are cost-effective and efficient than chemical fertilizers.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is not correct.
(d) Assertion is not correct, Reason is correct
(e) Both Assertion and Reason are not correct.
Answer:
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.

19. Assertion: Rhizobium is best suited for paddy fields, which increase yield by 15-40%.
Reason: This nitrogen-fixing bacterium when applied in soil undergoes multiplication in billions and fix nitrogen into a usable form for plants.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is not correct.
(d) Assertion is not correct, Reason is correct.
(e) Both Assertion and Reason are not correct.
Answer:
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.

20. Assertion: Trichoderma is symbiotic fungi, that are common in soil and root ecosystem.
Reason: They have been recognized as bio-control agent for plant disease.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is not correct.
(d) Assertion is not correct, Reason is correct.
(e) Both Assertion and Reason are not correct.
Answer:
(c) Assertion is correct, Reason is not correct.

21. Which of the following statement is correct?
(a) Most important green manure crops are Vinca rosea, Crotalaria and Thespecia.
(b) Most important green manure crops are Indigotera, Abitelon and Banian tree.
(c) Most important green manure crops are Crotalaria juncea, Tephrosia purpurea, and Indigofera tinctoria.
(d) None of the above.
Answer:
(c) Most important green manure crops are Crotalaria juncea, Tephrosia purpurea, and Indigofera tinctoria.

22. Choose the incorrect statement.
(a) The aim of plant breeding is to increase yield.
(b) The aim of plant breeding is to increase the fertility of crop.
(c) The aim of plant breeding is to increase tolerance to environmental conditions.
(d) All the above statements are not correct.
Answer:
(d) All the above statements are not correct.

23. Find out the correct statement.
(a) William S. Gaud coined the term mutation breeding.
(b) Muller and Stadler coined the term green revolution.
(c) M.S.Swaminathan is a pioneer mutation breeder.
(d) Nel Jayaraman hails from Andhra Pradesh.
Answer:
(c) M.S.Swaminathan is a pioneer mutation breeder.

24. Indicate the incorrect statement.
(a) Wheat variety Atlas 66 have high protein content.
(b) Wheat variety Atlas 66 have less protein content.
(c) Wheat variety Atlas 66 have been used as a donor for improving cultivated wheat.
(d) None of the above.
Answer:
(b) Wheat variety Atlas 66 have less protein content.

Students get through the TN Board 12th Bio Botany Important Questions Chapter 8 Environmental Issues which is useful for their exam preparation.

TN State Board 12th Bio Botany Important Questions Chapter 8 Environmental Issues

Very short answer questions

Question 1.
Define the greenhouse effect.
Answer:
The greenhouse effect is defined as a process by which the radiant heat from the sun is captured by gases in the atmosphere, leading to an increase in atmospheric temperature.

Question 2.
Define global warming.
Answer:
Global warming is a process through which the mean global temperature increases due to the increased concentration of greenhouse gases.

Question 3.
Mention any two natural sources of methane in the atmosphere.
Answer:

1. Paddy fields
2. Bacterial action in water bodies.

Question 4.
Expand CDM.
Answer:
CDM means Clean Development Mechanism.

Question 5.
Mention any two plants which can indicate SO2 pollution.
Answer:

1. Ficus
2. Pinus

Question 6.
What do you mean by social forestry?
Answer:
Social forestry refers to the management of forest and afforestation on barren lands with the purpose of helping the environmental, social, and rural development and benefits.

Question 7.
Mention any two causes of Deforestation.
Answer:

1. Agriculture plantation and livestock ranching are one of the main causes of deforestation.
2. Disproportionate felling of trees for timber.

Question 8.
Define Alien species.
Answer:
Alien species is defined as a non-native species to the ecosystem on the country, which poses a serious threat to the native species and ecosystem.

Question 9.
Name any two invasive plant species in India.
Answer:
The invasive plant species are:

1. Prosopis juliflora
2. Eichhornia crassipes.

Question 10.
Define Endemic species.
Answer:
Endemic species are defined as plants or animals that exist only in one geographic region.

Question 11.
Define carbon sequestration.
Answer:
Carbon sequestration is defined as a process through which capturing and storing of carbon-di-oxide in the atmosphere take place.

Question 12.
What is Biochar?
Answer:
Biochar is a long-term method to increase the ability of plants to store more carbon.

Question 13.
Expand EIA.
Answer:
EIA means Environmental Impact Assessment.

Short answer questions

Question 1.
Explain briefly about remote sensing.
Answer:
Remote sensing is the acquisition of information about an object without making physical contact with the object by measuring its reflected and emitted radiation at a distance from the target area. It gives exact pictures and data on the identification of even a single tree in a large area of vegetation and wildlife. It is also helpful in the identification of biodiversity-rich or fewer areas for futuristic works on conservation and restoration of biota. It helps in the maintenances of various species including commercial crops, medicinal plants, and threatened plants.

Question 2.
What is biomonitoring? Explain it briefly.
Answer:
Biomonitoring is the act of observing and assessing the current state and changes in the ecosystem, biodiversity components, landscape including natural habitat, population, and species. Eg: In an agricultural drone, a bird’s eye view of a farmer can reveal many issues like irrigation problems, soil variation, and pests as well as fungal infestation. It is used in farming in order to help increased crop production and monitor crop growth. It is also helpful for a cost-effective safe methods of spraying pesticides and fertilizer.

Question 3.
Invasion of alien species disrupts ecosystem processes. Justify.
Answer:
The alien species disrupt ecosystem processes, because

1. They threaten biodiversity, reduce native herbs, reducing ecosystem services (benefits).
2. They only alter the ecosystem and micro intimate by prolific spreading.
3. They also alter the nature of the soil and make it unsuitable for native species.
4. They create human health problems like allergies.
5. Thus they degrade the local environment and eliminate important local species.

Question 4.
Mention any three achievements of the Afforestation project.
Answer:

1. Degraded forests were restored.
2. Environmental and ecological stability was maintained.
3. Afforestation was helpful to conserve bio-diversity, wildlife, and genetic resources.

Question 5.
Distinguish between Agroforestry and social forestry.
Answer:

Agroforestry	Social forestry
Agroforestry is an integration of trees crops and livestock on the same piece of land.	Social forestry refers to the management of forests and afforestation on barren lands.
Main objective of this is to build interaction among above components.	Main objective includes helping environmental, social and rural development and their benefits.
Intercropping of two or more crops between different species of trees and shrubs resulting in higher yield and reduction in operation cost.	Social forestry programme is carried out for the benefit of people and participation of people in order to reduce pressure on forest.

Question 6.
Mention any three major activities of forestry extension centers.
Answer:

1. Imparting training to the public on tree growing methods.
2. Publicity and propaganda of the advantage of tree growing,
3. Raising the seedlings of important tree species and supply to the public with subsidies.

Question 7.
Write down any three effects of- global warming on plants.
Answer:

1. Global warming leads to low agricultural productivity.
2. Weeds, pests, and fungi which need warmer temperature, will increase in number due to global warming.
3. Global warming may change the flowering seasons and pollinators.

Question 8.
Mention any three causes of greenhouse gas emission.
Answer:

1. Agriculture practices and animal husbandry practices lead to the emission of CH₄.
2. CO₂ and CH₄, are produced by burning fossil fuels.
3. The household items like electrical gadgets including refrigerators and air conditioners release chlorofluorocarbon.

Long answer questions

Question 1.
List the objectives of Afforestation:
Answer:

1. One of the prime objectives of Afforestation is to increase forest cover by planting more trees, which increases O₂ production and air quality.
2. Rehabilitation of degraded forests to increase CO₂ fixation, leading to reduction of atmospheric carbon dioxide.
3. Medicinal plants are planted in mixed plantations and produce natural medicines.
4. Regeneration of indigenous herbs and shrubs.
5. The other objectives include the increase of availability of water table or groundwater, reduction of nitrogen leaching from the soil, and reduction of nitrogen contamination of drinking water.

Question 2.
List the plants used as plant indicators of pollutions.
Answer:

Plants	Indicator for pollutants
Ficus, Lichens, Pinus, and Rose.	SO2 Pollution.
Petunia and Chrysanthemum	Nitrate contamination.
Gladiolus	Fluoride pollution.
Robinia pseudo­acacia (Black locust tree)	Indicator of heavy metal contamination.

Question 3.
Distinguish between in-situ and ex-situ conservation.
Answer:

In-situ Conservation	Ex-situ conservation
In insitu conservation, the conservation of management of genetic resources in their natural habitats	In ex-situ conservation the species are protected outside their natural environment.
In this method, forest trees, medicinal and aromatic plants under thread are conserved within the existing habitat.	The plants are conserved is botanical gardens, and following some of conservation strategies like gene, pollen, seed in-vitro conservation cryo preservation, seedling, tissue culture and DNA banks.

Question 4.
Write about Biodiversity impact Assessment. How will you assess the impact?
Answer:
Biodiversity Impact Assessment (BIA) can be defined as a decision-supporting tool to help the development considering bio-diversity as an inclusive component followed by planning and implementation.
It integrates biodiversity consideration for developmental proposals.
They are legally bound mechanisms for implementing the conservation of biodiversity resources. They also provide fair and equitable sharing of the benefits arising from the use of bio-diversity.
The Bio-diversity impacts can be assessed by:

1. Change in land use and cover.
2. Fragmentation and isolation.
3. Extraction.
4. External inputs such as emissions, effluents, and chemicals.
5. Introduction of invasive, alien, or genetically modified species.
6. Impact on endemic and threatened flora and fauna.

Question 5.
List the importance of GIS.
Answer:

1. GIS is used in Environmental Impact Assessment.
2. It is also helpful in disaster management.
3. It is used in the zoning of landslide hazards.
4. It helps in the determination of land cover and land use.
5. It is used to determine flood damage.
6. It is used in the management of natural resources.
7. Soil mapping and wetland mapping can be done using GIS.
8. Identification of volcanic hazards and irrigation management can be carried out by this information.
9. It helps to study vegetation and to map threatened and endangered species.

Activity

Students may form ‘ECOGROUPS’ and discuss eco-issues of their premises and find solutions to the existing problems like litter disposal, water stagnation, health, and hygiene, greening the campus, and its maintenance.
Eco groups discussion topics:

1. Litter disposal: The litter forms solid waste which includes degradable and non-degradable waste. The degradable waste can be degraded to manure using bacteria and earthworms. Non- degradable waste like plastic can be recycled.
2. Water stagnation: Solution: Setting up of water harvesting system will solve water stagnation.
3. Health and hygiene: Solution: Keep the surroundings clean and neat. Follow personal hygiene strictly. Create awareness among the public.
4. Greening the campus: Solution: A tree planting programme may be initiated in the campus. Each member of Eco groups may be given responsibility for maintaining one or two trees in the campus.

Multiple choice questions

1. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)
Answer:
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

2. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(c) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)

3. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
Answer:
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)

4. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
Answer:
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

5. Choose the odd man out.
(a) Sudhir kumar Sopary.
(b) Jadav molai Payeng
(c) Panduranga Hegde
(d) Swaminathan
Answer:
(d) Swaminathan

6. Find out the odd one.
(a) Western ghat
(b) National park
(c) Gulf of mannar
(d) Agasthiar malai
Answer:
(c) Gulf of mannar

7. Indicate the odd one (Ex-situ conservation)
(a) Pollen
(b) Seed
(c) Seedling
(d) Leaf
Answer:
(d) Leaf

8. Choose the odd one:
(a) Carbon-di-oxide
(b) Ammonia
(c) Methane
(d) Nitrous oxide
Answer:
(b) Ammonia

9. Choose the incorrect pair.

Answer:
(c)

10. Choose the incorrect pair?

Answer:
(d)

11. Which of the following is a correct pair?

Answer:
(a)

12. Choose the incorrect pair:

Answer:
(c)

13. Find out the plant indicator. depletion.
(a) Water Lilly
(b) Coconut
(c) Acacia sp
(d) Gladiolus
Answer:
(d) Gladiolus

14. Ozone depletion in the atmosphere results in:
(a) UV radiation
(b) CO₂ emission
(c) Nitrogen depletion
(d) Afforestation
Answer:
(a) UV radiation

15. Which of the following is a hedge plant.
(a) Azadirachta indica
(b) Acacia spp
(c) Teak
(d) Eucalyptus
Answer:
(b) Acacia spp

16. Alien invasive species include.
(a) Casuarina
(b) Amelia dubia correct.
(c) Prosopis juliflora
(d) Bamboo
Answer:
(c) Prosopis juliflora

17. Assertion: Majority of endemic species are threatened.
Reason: Because of their narrow specific habitat, reduced seed production low dispersal rate, less viable nature and human interference.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is not correct.
(d) Both Assertion and Reason are not correct.
(e) Assertion is not correct, Reason is correct.
Answer:
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.

18. Assertion: Eichhornia crassipes increases the oxygen content of water bodies.
Reason: Anoxic condition in water bodies leads to Eutrophication.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is not correct.
(d) Both Assertion and Reason are not correct.
(e) Assertion is not correct, Reason is correct.
Answer:
(e) Assertion is not correct, Reason is correct.

19. Assertion: In plants, photosynthetic chemicals will be affected due to ozone depletion.
Reason: Decreased photosynthesis will result in increased atmospheric CO₂, resulting in global warming.
(a) Both Assertion and R are correct, R is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is not correct.
(d) Both Assertion, and Reason are not correct.
(e) Assertion is not correct, Reason is correct.
Answer:
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.

20. Assertion: In Agroforestry, nutrient cycling between species improves and organic matter in the soil is maintained.
Reason: Because of the absence, of microorganisms, insects, and earthworm in the soil.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are Correct, Reason is not the correct explanation of Assertion.
(c) Assertion is correct, Reason is not correct
(d) Both Assertion and Reason are not correct.
(e) Assertion is not correct, Reason is correct.
Answer:
(c) Assertion is correct, Reason is not correct

21. Which of the following statement is correct?
(a) Trees provide microclimate for crops.
(b) They disturb O₂-CO₂ balance.
(c) Trees increase atmospheric CO₂.
(d) Trees cause decrease in relative humidity in atmosphere.
Answer:
(a) Trees provide microclimate for crops.

22. Choose the incorrect statement.
(a) Ozone depletion increases the incidence of cataract in human.
(b) It also causes lung irritation.
(c) Ozone depletion enhances the functioning of immune system.
(d) It increases the incidence of mutation:
Answer:
(c) Ozone depletion enhances the functioning of immune system.

23. Find out the correct statement.
(a) Prosophis juliflora is a native species found in Tamil Nadu.
(b) It is an aggressive coloniser.
(c) It is an invasive species native of South Africa.
(d) None of the above.
Answer:
(b) It is an aggressive coloniser.

24. Indicate the incorrect statement.
(a) Hardwickia binata is an endemic tree.
(b) It is endemic to peninsular and northern India.
(c) It is endemic to Kerala and Tamil Nadu.
(d) None of above.
Answer:
(c) It is endemic to Kerala and Tamil Nadu.

Students get through the TN Board 12th Bio Botany Important Questions Chapter 7 Ecosystem which is useful for their exam preparation.

TN State Board 12th Bio Botany Important Questions Chapter 7 Ecosystem

Very short answer questions

Question 1.
Define ecosystem.
Answer:
The ecosystem is defined as the structural and functional unit of ecology.

Question 2.
Mention the major components of the ecosystem.
Answer:

1. Abiotic components – Nonliving
2. Biotic components – Living

Question 3.
What is Photosynthetically Active Radiance (PAR)?
Answer:
Photosynthetically Active Radiation is the amount of light available for the photosynthesis of plants.
This is the range between 400-700 nm wavelength.

Question 4.
Give any two functions of the ecosystem.
Answer:

1. Energy cycling
2. Cycling of materials between the living and non-living components.

Question 5.
Define productivity.
Answer:
Productivity is defined as the rate of biomass production per unit area in a unit of time.

Question 6.
Define community productivity.
Answer:
Community productivity is defined as the rate of net synthesis of organic matter by a group of plants per unit area in a unit of time.

Question 7.
What is meant by the food web?
Answer:
Food web is a web like arrangement in which the interlocking pattern of a number of food chain exist.

Question 8.
Define ecological pyramid.
Answer:
An ecological pyramid is defined as the graphic representation of trophic structure and function at successive trophic levels of an ecosystem.

Question 9.
Explain Humification.
Answer:
Humification is a process by which the dark-colored amorphous substance (humus) is formed from simplified detritus.

Question 10.
Mention the types of freshwater ecosystems.
Answer:

1. Lotic – running water bodies.
2. Lentic – Standing water bodies.

Question 11.
Mention any two phytoplankton in the pond ecosystem.
Answer:

1. Oscillatoria
2. Anabaena

Question 12.
The photosynthesis is more in a limnetic zone of the pond. Why?
Answer:
The photosynthesis is more in the limnetic zone of a pond, because of the greater penetration of i sunlight.

Question 13.
Mention any two cultural services of the ecosystem.
Answer:

1. Education and inspiration.
2. Spiritual and religious values.

Question 14.
List out two factors, which affect the ecosystem.
Answer:

1. Deforestation and over-grazing.
2. Habitat destruction.

Question 15.
What is ecosystem resilience?
Answer:
Ecosystem resilience is the ability of the ecosystem to resist damage caused by disturbances from flood, fire, infection, predation drought, etc., and recover quickly.

Short answer questions

Question 1.
Explain briefly about autotrophic succession.
Answer:
Autotrophic succession is the condition, in which the green plants are dominant during the early stage of succession. If the soil is rich in inorganic substances, this succession occurs. As the green plants dominate at the beginning of this succession, an increase in organic matter in the ecosystem results. The energy flow subsequently increases in the ecosystem.

Question 2.
Describe the different levels of consumers in the pond ecosystem.
Answer:
In the pond ecosystem, the primary consumers include zooplanktons like Paramoecium, Daphnia, etc., The bottom-dwelling benthic organisms include mollusks and annelids. The water beetle and frogs form the secondary consumers. Ducks and cranes constitute the tertiary consumers (carnivores). Large fish, hawk man, etc., are the top carnivores in the pond ecosystem.

Question 3.
Distinguish between lotic and lentic ecosystems.
Answer:

Lotic Ecosystem	Lentic Ecosystem
It is running water ecosystem.	It is standing water body.
It includes river spring and stream.	It includes ponds and lakes.
In times of drought shallow systems will dry up and many organism will die.	During periods of drought these systems will often last longer than its counterpart.

Question 4.
Explain ten percent law.
Answer:
Lindeman in 1942 proposed a ten percent law. This law states that when the energy is transferred from one trophic level to another trophic level, only 10% of food energy is stored at every level. The rest of food energy (90%) is lost through respiration, decomposition, and in the form of heat. Hence this law is called the ten percent law.

Question 5.
Distinguish between macro consumers and micro consumers.
Answer:

Macro consumers	Micro consumers
Macro consumers refer to herbivores, carnivores, omnivores.	Micro consumer are decomposers.
They are primary secondary and tertiary consumers	Organisms that decompose dead plants and animals to release organic and inorganic nutrients, which are reused by plants.
Eg: Rabbit, hawk, lion etc.	Eg: Bacteria, Actinomycetes, Fungi etc.

Question 6.
Write a diagrammatic representation of energy flow.
Answer:

Question 7.
Write down the significance of the food web.
Answer:

1. The Food web is made to explain species interaction (Direct interaction).
2. It is also helpful to illustrate indirect interaction among different species.
3. It can be used to study the community structure of an ecosystem.
4. Food web can be used to reveal different patterns of energy flow in terrestrial and aquatic ecosystems.

Long answer questions

Question 1.
Write in detail about the concept of trophic level in an ecosystem.
Answer:
The position of an organism in a food chain is referred as a trophic level. The number of steps in a food chair is equal to the number of trophic levels in an ecosystem.
The first trophic level (T₁) is occupied by green plants and they are called producers.
The primary consumers are in the second trophic level (T₂) and they utilize the energy produced by the producers. They are called herbivores. The herbivores are eaten by carnivores and they occupy the third trophic level (T₃). They are also called secondary consumers or primary carnivores. The fourth trophic level (T₄) is occupied by carnivores which eat on primary carnivores. They are otherwise known as tertiary consumers or secondary carnivores. The omnivores eat ‘ both plants and animals. They may occupy more than one trophic level in the food chain.

Question 2.
Explain food web with suitable diagram.
Answer:
Food web is a web like arrangement in which the interlocking pattern of a number of food chain can exist. It is the basic unit of an ecosystem, to maintain its stability in nature. It is otherwise known as homeostasis.
Eg: In a grazing food chain of a grass land, a mouse may also eat food grains in the absence of rabbit in the ecosystem. The mouse in turn may be eaten directly by a hawk or by a snake and a snake may directly be eaten by hawk.
Therefore, the interlocking pattern of the food chain is the food web. The species of an ecosystem may remain balanced to. each other by some sort of natural check.

Question 3.
Draw the diagrammatic representation of pyramids of biomass in different types of ecosystems.
Answer:

Question 4.
How do anthropogenic activities affect ecosystem services?
Answer:
Human being and their activities make the destruction of the ecosystem. We all exploit nature than that of our needs. The ecosystem is exploited in order to meet rapidly growing demands for food, freshwater, medicine, timber, fiber and fuel. The deterioration, caused by present-day human activities changed the ecosystem rapidly and extensively than in any comparable period of time in human history.
The followings are factors caused by human activities which disturb an ecosystem.

1. The destruction of habitats.
2. Deforestation and over-grazing.
3. Erosion of soils.
4. Introduction of alien species.
5. Overharvesting of plant material.
6. Pollution of land, water, and air.
7. Runoff pesticides, fertilizers, and animal waste.

Question 5.
Write down the strategies of ecosystem management.
Answer:
The strategies of ecosystem management are as follows.

1. The biodiversity of ecosystems ought to be maintained.
2. Flagship species are the species that indicate the health of the ecosystem. This helps in indicating the damaged ecosystem.
3. It is helpful to recognize the inc it Vilify of ecosystem change and plans accordingly.
4. The sustainability of the ecosystem through sustainable development can be achieved by a strategy of ecosystem management.
5. The ecosystems, which are in need of rehabilitation can be identified by this strategy.
6. The management strategy involves government agencies, the local population, communities, and NGOs.
7. To build the capacity of local institutions and communities in order to create responsibility for the long-term implementation of ecosystem management activities.

Choose the correct answers.

1. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(ii)
Answer:
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)

2. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(u); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
Answer:
(a) (p)-(iv); (q)-(iii); (r)-(u); (s)-(i)

3. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

4. Match the following.

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(c) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(d) (p)-(iii); (q)-(i): (r)-(iv); (s)-(ii)
Answer:
(d) (p)-(iii); (q)-(i): (r)-(iv); (s)-(ii)

5. Match the following.

(a) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(b) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(c) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
Answer:
(a) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)

6. Which of the following is not a biotic factor?
(a) Bacteria
(b) Fungi
(c) Carbohydrate
(d) Algai
Answer:
(c) Carbohydrate

7. Which of the following is an omnivore?
(a) Eagle
(b) Crow
(c) Rabbit
(d) Hawk
Answer:
(b) Crow

8. The movement of decomposed water-soluble organic and inorganic compounds from the surface to the lower layer of soil is called:
(a) Eluvation
(b) Filtration
(c) Sublimation
(d) Diffusion
Answer:
(a) Eluvation

9. Gaseous cycle in the atmosphere includes:
(a) Ammonia, oxygen and methane cycle
(b) Oxygen, nitrogen and ammonia cycle
(c) Oxygen, carbon, and nitrogen cycle
(d) Carbon dioxide, nitrogen, and methane cycle
Answer:
(c) Oxygen, carbon, and nitrogen cycle

10. Identify the regulating service of the ecosystem:
(a) Nutrient cycle
(b) Erosion
(c) Education value
(d) Medicines
Answer:
(b) Erosion

11. Choose the odd man out:
(a) Vernadsky
(b) Karl Mobius
(c) Watson
(d) Friederichs
Answer:
(c) Watson

12. Find out the odd one out:
(a) Mouse
(b) Deer
(c) Elephant
(d) Tiger
Answer:
(d) Tiger

13. Indicate the odd one out:
(a) Fragmentation
(b) Infiltration
(c) Catabolism
(d) Humification
Answer:
(b) Infiltration

14. Choose the odd one out:
(a) Forest
(b) Pond
(c) Maize field
(d) Lentic
Answer:
(c) Maize field

15. Identify the odd one out:
(a) Water cycling
(b) Seed dispersal
(c) Pest regulation
(d) Water purification
Answer:
(a) Water cycling

16. Which of the following is a correct pair?

Answer:
(c)

17. Find out the incorrect pair.

Answer:
(c)

18. Choose the correct pair.

Answer:
(b)

19. Identify the incorrect pair.

Answer:
(d)

20. Which of the following is the correct pair?


Answer:
(c)

21. Assertion: |n m0st ecosystems, green plants are autotrophs.
Reason: They have chlorophyll, which enables them to produce carbo-hydrate from simple inorganic components.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is false. The reason is true.
(d) Assertion and Reason are false.
Answer:
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.

22. Assertion: The product of starch is formed during photosynthesis by the combination of reactants such as chlorophyll, H₂O and carbon dioxide.
Reason: The energy stored in starch is obtained from the external source (light energy from sun)
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is false, Reason is true.
(d) Assertion and Reason are false.
Answer:
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.

23. Assertion: In a forest ecosystem, the pyramid of numbers is somewhat different in shape.
Reason: The pyramid of numbers in the forest ecosystem looks spindle-shaped.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is hot the correct explanation of Assertion.
(c) Assertion is false, Reason is true.
(d) Assertion and Reason are false.
Answer:
(b) Assertion and Reason are correct, Reason is hot the correct explanation of Assertion.

24. Assertion: Seagrasses and mangroves of Estuarine and coastal ecosystems are called as blue carbon ecosystems.
Reason: They are more efficient in carbon sequestration.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is false, Reason is true.
(d) Assertion and Reason are false.
Answer:
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.

25. Assertion: By 2025, at least 90% of the world’s population is projected to face water scarcity.
Reason: By 2025, 70% of forest cover will be destroyed.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is false, Reason is true.
(d) Assertion and Reason are false.
Answer:
(d) Assertion and Reason are false.

26. Which of the following statement is correct?
(a) Cultural services of the ecosystem include Ecotourism.
(b) Cultural services of the ecosystem include water purification.
(c) Cultural services of the ecosystem include water cycling.
(d) None of the above.
Answer:
(a) Cultural services of the ecosystem include Ecotourism.

27. Choose the incorrect statement:
(a) Mangrove ecosystem offers habitat for aquatic plants and animals.
(b) Mangrove ecosystem acts as a nursery for aquatic animals.
(c) It helps salt spray from waves.
(d) It provides medicine, fuelwood, and timber.
Answer:
(c) It helps salt spray from waves.

28. Find out the correct statement.
(a) The pyramid of energy is always spindle-shaped.
(b) The Pyramid of energy is always upright
(c) The pyramid of numbers in the forest ecosystems is always inverted.
(d) None of the above.
Answer:
(b) The Pyramid of energy is always upright

29. Indicate the incorrect statement.
(a) Ten-point law was proposed by Lindeman.
(b) The concept of ecological pyramids was introduced by Charles Elton.
(c) The ecosystem was defined by Odum
(d) All the above statements are not correct.
Answer:
(d) All the above statements are not correct.

30. Indicate the correct statement.
(a) All the primary producers are autotrophs.
(b) All the consumer are carnivores
(c) All the herbivores are only grass eaters.
(d) None of the above.
Answer:
(a) All the primary producers are autotrophs.

Students get through the TN Board 12th Bio Botany Important Questions Chapter 6 Principles of Ecology which is useful for their exam preparation.

TN State Board 12th Bio Botany Important Questions Chapter 6 Principles of Ecology

Very short answer questions

Question 1.
What is paleoclimatology?
Answer:
Paleoclimatology is a branch of climatology, which helps to reconstruct past climates of our planet and flora, fauna, and ecosystem in which they lived.
Eg: Air bubbles trapped in ice for tens of thousands of years with fossilized pollen, coral, plant, and animal debris.

Question 2.
What is meant by Heliophytes? Give example.
Answer:
Heliophytes are light-loving plants. Eg: Angiosperm.

Question 3.
What is Timberline?
Answer:
Timberline or tree line is an imaginary line in a mountain or higher areas of land, beyond which trees do not grow. This limit is calculated to be about 3000 to 4000m.

Question 4.
Name the gases present in the atmosphere.
Answer:

1. Nitrogen – 78%
2. Oxygen – 21%
3. Carbon dioxide – 0.03%
4. Argon and other gases – 0.93%

Question 5.
Name any two plants that used for phytoremediation of cadmium.
Answer:

1. Rice
2. Eichhomia

Question 6.
What is pyrophilous fungi? Give an example.
Answer:
Pyrophilous fungi are the fungi that grow in the soil of burnt areas after the fire.
Eg: Pyroriema confluence.

Question 7.
Explain briefly about the Edaphic factor.
Answer:
Edaphic factors are abiotic factors of soil.
It includes the composition of the soil in an area, including the physical and chemical composition of the soil.

Question 8.
What are soil organisms?
Answer:
The soil organisms are the living organisms, which live in the soil.
Eg: Bacteria, fungi, algae, protozoans, nematodes, insects, earthworms, etc.

Question 9.
Define cryptophytes.
Answer:
Cryptophytes are the plants that live below the surface of the soil.

Question 10.
Define Edge effect.
Answer:
Edge effect is defined as the phenomenon in which an organism or species are seen in ecotone areas due to the effect of an environment of two habitats.
Eg: Owl present between the forest and grassland area.

Question 11.
Name any two nitrogen-fixing bacteria.
Answer:

1. Anabaena
2. Nostoc

Question 12.
What is the negative interaction of species?
Answer:
In negative interaction of species, one species is benefited and the other is harmed.

Question 13.
Mention any two plants, which show defensive mechanisms against their predators.
Answer:

1. Tobacco produces nicotine
2. Opuntia has spines.

Question 14.
Define Amensalism.
Answer:
Amensalism is the phenomenon of the interaction of two species, in which one is inhibited by the secretion of certain chemical substances. The other species is neither harmed nor benefited.

Question 15.
Name any two amphibious plants.
Answer:

1. Typha
2. Sagittaria

Question 16.
Mention any two root morphological adaptations in hydrophytes.
Answer:

1. Roots are totally absent in Wolffia and Salvinia.
2. The root pockets replace root caps. Eg: Eichhornia.

Question 17.
Mention any two stem modifications in xerophytes for example.
Answer:

1. Cladode in Asparagus
2. Phylloclades in Opuntia

Question 18.
What are Tropophytes?
Answer:
Tropophytes are plants that act as xerophytes during summer and act as mesophytes or hydrophytes during the rainy season.

Question 19.
Define Autochory. Give example.
Answer:
Autochory is a process through which seed disperse takes place by a sudden burst of fruit with a force enabling to throw the seeds little away from the parent plant.
Eg: Impatients, crossandra.

Question 20.
Explain briefly about pneumatophores.
Answer:
Pneumatophores are special types of roots present in halophytes. They are negatively geotropic and respiratory in function.
Eg: Avicennia.

Short answer questions

Question 1.
Distinguish between Autecology and synecology.
Answer:

Autecology	Synecology
Autecology is the ecology of an individual species.	Synecology is the ecology of population or community.
It is also called as species ecology.	It is also called as community ecology.

Question 2.
Explain commensalism with a suitable example.
Answer:
Commensalism is an interaction between two organisms. In this type, one organism is benefited, while the other is neither harmed nor benefited. The organism, that is benefited is called the commensal, and other organisms are the host.
Eg: The plants like Vanda, growing on other plants without harming the host. These plants are called epiphytes and are commonly seen in the tropical rain forest.

Question 3.
Give examples of tolerance to cadmium toxicity in the soil.
Answer:

1. Plants like soybean and tomato can tolerate high concentrations of cadmium in the soil. They isolate cadmium and storing into few groups of cells. This in turn prevents the cadmium from affecting other cells.
2. Plants like rice and Eichhomia can tolerate cadmium but binding it to their proteins.
   These plants can be used to remove cadmium from contaminated soil.

Question 4.
Vegetation at different altitudes varies, showing distinct zonation why?
Answer:
Vegetation at different altitudes varies because of the following reasons:

1. The velocity of wind remains high at high altitudes.
2. The atmospheric temperature and air pressure decrease with an increase in height in high altitudes.
3. The timidness and intensity of light increase at high altitudes.

Question 5.
Name any three plants which show a defense mechanism against predators. Mention their mechanisms.
Answer:

1. Cinchona – Produces a chemical compound, quinine.
2. Bougainvilla – has thorns that produce it from animals.
3. Cacti – Produces latex, which protects them from predators.

Question 6.
Give any three examples of Amensalism.
Answer:

1. Penicillin produced by Penicillium notation inhibits the dying growth of a variety of bacteria, especially Staphylococcus.
2. The growth of fungus, Aspergillus is inhibited by Trichoderma.
3. An alkaloid, the jungle is secreted by roots and hulls of black walnut, Juglans nigra, inhibits the growth of seedlings of apple, tomato, and Alfalfa around it.

Question 7.
Name any three plants, which are called rooted submerged hydrophytes.
Answer:

1. Vallisneria
2. Hydrilla and
3. Isoetes.

Question 8.
What are the stem adaptations in hydrophytes?
Answer:
In hydrophytes the stem is adapted to suit the aquatic mode of life as follows:

1. In submerged plants, the stem is long, slender, spongy, and flexible.
2. In free-floating plants, a thick, short, stoloniferous, and spongy stem is present while in rooted floating forms, the stem is modified as a rhizome.
3. The vegetative propagation is also done through stem cuttings and their modifications like a rhizome, runners, etc.

Question 9.
What are the different types of xerophytic habitat? Explain them.
Answer:
There are two types of xerophytic habitats namely physical and physiological.

1. Physical dryness: In these habitats, the soil has a little amount of water due to low rainfall and the inability of the soil to retain water.
2. Physiological dryness: In this habitat, the plants are unable to absorb water, because of the absence of capillary spaces, even though sufficient water is available.
   Eg: Plants in salty and acidic soil.

Question 10.
Mention any three adaptations in the seeds and fruits of hydrochory plants.
Answer:
The plants which grow in or near water bodies, disperse their seeds, fruits through the water. They have certain adaptations for the dispersal of seeds and .fruits and they are:

1. The fruits of some plants like, Nelumbo have open coel receptacle with prominent air Space for floating.
2. In plants like coconut, the presence of fibrous mesocarp and light percap aids the fruits to float in water.
3. In plants like Heritiera littoralis, the fruits may be inflated, so that it can float in water.

Long answer questions

Question 1.
What is Autochory? Give an account of adaptations in fruits of autochory plants.
Answer:
Autochory is one of the types of seed dispersal, through which the seeds are dispersed by a sudden burst of fruits with a force. Autochory shows the following adaptations.

1. In some plants, the ripened fruits explode suddenly and seeds are dispersed with of great force by the mere touch of the plant. Eg: Inpatient (Balsam), Hura
2. In some plants, the fruits burst with noise and scatter the seeds, when they come in contact with water due to a shower of rain. Eg: Ruellia and Crassandia.
3. Some long pods explode with a loud noise like a cracker, dispersing the seeds in all directions. Eg: Bauhinia viable.
4. In some fruits, the dispersal of seeds takes place due to a high turgor pressure developed inside the fruit, when tissues around seeds are converted into a mucilaginous fluid. Eg: Ecballium elaterium, Gyrocarpus, and Dipterocarpus.

Question 2.
List out the anatomical adaptions of epiphytic plants. Draw and label the T.S section of the aerial root of an orchid.
Answer:

1. The roots of these plants have multilayered epidermis. The Exodermis layer is present inner velamen tissue.
2. The transpiration is reduced due to the presence of thick cuticle and sunken stomata.
3. Well-developed parenchymatous cells to store water is present in succulent epiphytes.
   

Question 3.
Give an account of an Example of Mutualism in the plant kingdom.
Answer:
Mutualism is an interaction between two species in which both species are benefited from obligate association. The common examples of mutualism are as follows.

1. The bacteria, Rhizobium lives in the nodules of leguminous plants, establishing a symbiotic association. The bacteria fix atmospheric nitrogen into nitrate for the leguminous plant, which in turn supplies food to the bacteria.
2. The association of water fem (Azolla) and nitrogen-fixing cyanobacterium (Anabaena) is a mutualism, in which the bacteria harbors in the water fem will fix atmospheric nitrogen for the Azolla.
3. The nitrogen-fixing Anabaena is present in coralloid roots of cycas (Gymnosperm) fixes atmospheric nitrogen into nitrate, making it available for the host cycas. The cycas provide food for the bacteria.
4. The association of cyanobacterium (Nostoc) found in the thalloid body of. Bryophyte (Anthoceros) is a mutual association. In this, the bacteria fix atmospheric nitrogen and the Bryophyte into supplies shelter and food to the cyanobacterium.
5. Other mutual associations are:
   (a) Wasps present in fruits of fig.
   (b) The association of algae and a fungus is the Lichen.
   Micorrhiza is the mutual association of roots of tropical plants and fungal hyphae.

Question 4.
List out the effects of wind on plants.
Answer:

1. The wind is one of the important factors for the formation of rain.
2. Wind promotes the aeration of water by creating waves in lakes and the ocean.
3. Soil erosion is caused by strong wind. This in turn reduces soil fertility.
4. The rate of transpiration is increased by the wind.
5. It helps in pollination in anemophilous plants.
6. The dispersal of fruits, seeds, spores, etc., is carried out by the wind.
7. The uprooting of the big trees may be caused by a strong wind.
8. The development flag forms in trees are caused by unidirectional wind.

Question 5.
List out the important edaphic factors which affect vegetation in an area.
Answer:

1. Soil moisture: Plants absorb water from the soil. Some plants absorb moisture from the atmosphere.
2. Soil water: The distribution of plants greatly depends on the soil water. The main source of soil water is rain. In soil, water is held between pore spaces of soil particles and angles between them and this forms the most important form of water available to the plants for absorption.
3. Soil reactions: The availability of soil nutrients mainly depend on the pH of the soil. Soil may be acidic, alkaline, or neutral in its reaction. The pH range of 5.5 to 6.8 is ideal for the cultivation of crop plants.
4. Soil nutrients: All essential plant nutrients such as mineral and organic nutrients in the form of ions decide the fertility of the soil, which determines the plant growth and vegetation.
5. Soil temperature: As low temperature reduces the use of water and solute absorption by roots, the geographical distribution of plants is mainly decided by soil temperature.
6. Soil atmosphere: The spaces between soil particles are occupied by oxygen and carbon-di-oxide. This forms soil aeration or soil atmosphere.
7. Soil Organisms: Many organisms like bacteria, fungi, algae, protozoans, nematodes, insects, earthworms, etc., are present in the soil. They are responsible for making the soil suitable for plant growth.

TN Board 12th Bio Botany Important Questions

Choose the correct answers:

1. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
Answer:
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

2. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(c) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(c) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)

3. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
Answer:
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

4. Match the following:

(a) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(b) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)
Answer:
(a) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

5. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(ii); (q)-(iii); (r)-(iv); (s)-(i)
Answer:
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

6. Choose the odd one out.
(a) Rhizobium
(b) Cuscuta
(c) Anabaena
(d) Nostoc
Answer:
(b) Cuscuta

7. Find out the odd one out (Defensive mechanism).
(a) Nicotine
(b) Quinine
(c) Penicillin
(d) Caffeine
Answer:
(c) Penicillin

8. Indicate the odd one out.
(a) Mimicry
(b) Myrmecophily
(c) Co-evolution
(d) Epiphyte
Answer:
(d) Epiphyte

9. Choose the odd one out.
(a) Balanophora
(b) Loranthus
(c) Nepenthes
(d) Sandalwood
Answer:
(c) Nepenthes

10. Identify the odd one out:
(a) Nelumbo
(b) Morsilea
(c) Nymphaea
(d) Utricularia
Answer:
(d) Utricularia

11. Which of the following is the correct pair:

Answer:
(b)

12. Which of the following in the incorrect pair?

Answer:
(c)

13. Which of the following in the correct pair?

Answer:
(b)

14. Choose the incorrect pair:

Answer:
(d)

15. Which of the following in the correct pair seed dispersal?

Answer:
(a)

16. Assertion: Mango plants cannot grow in temperate countries like Canada.
Reason: They are stenothermal plants and they cannot tolerate a wide range of temperatures.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is false, Reason is correct.
(d) Both Assertion and Reason are false.
Answer:
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.

17. Assertion: Temperature affects all biochemical reactions in the plant body.
Reason: It influences CO₂ and O₂ solubility in biological systems.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is false, Reason is correct.
(d) Both Assertion and Reason are false.
Answer:
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.

18. Assertion: Gases let out to the atmosphere causes climate change.
Reason: It is due to the Albedo effect.
(a) Both Assertion and Reason are correct. The reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct. The reason is not the correct explanation of Assertion.
(c) Assertion is false, Reason is correct.
(d) Both Assertion and Reason are false.
Answer:
(b) Both Assertion and Reason are correct. The reason is not the correct explanation of Assertion.

19. Assertion: Epiphytic plants like orchids get their nutrients and water from the atmosphere.
Reason: Because they have hygroscopic roots, which contain a special type of spongy tissue called velamen.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is false, Reason is correct.
(d) Both Assertion and Reason are false.
Answer:
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.

20. Assertion: Vallisneria is adapted to both aquatic and terrestrial modes of life.
Reason: It is an amphibious hydrophyte.
(a) Both Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is false, Reason is correct.
(d) Both Assertion and Reason are false.
Answer:
(d) Both Assertion and Reason are false.

21. Eichhornia is a:
(a) Rooted floating hydrophyte
(b) Free-floating hydrophyte
(c) Submerged floating hydrophyte
(d) Amphibious hydrophyte
Answer:
(b) Free-floating hydrophyte

22. The interaction between mango free and ants called:
(a) Mimicry
(b) Co-evolution
(c) Myrmecophily
(d) Amensalism
Answer:
(c) Myrmecophily

23. Forest fire is classified under:
(a) Climatic factor
(b) Edaphic factor
(c) Topographic factor
(d) Biotic factor
Answer:
(a) Climatic factor

24. Organisms that can live in water with a wide range of salinity is called:
(a) Stenothemal
(b) Eurythermal
(c) Euryhaline
(d) Stenohaline
Answer:
(c) Euryhaline

25. Seed dispersal in Gyrocarpus in by:
(a) Hydrochoiy
(b) Zoochory
(c) Autochory
(d) Anemochory
Answer:
(d) Anemochory

26. Which of the following statement is correct?
(a) The pneumatophores are a special type of positively geotropic roots in Avicennia.
(b) They absorb water and nutrients from the atmosphere.
(c) The pneumatophores are a special type of negatively geotropic roots in Avicennia.
(d) They are called hydrographic roots.
Answer:
(c) The pneumatophores are a special type of negatively geotropic roots in Avicennia.

27. Indicate the incorrect statement.
(a) Phylloclades are present in Opuntia.
(b) Phyllode is present is Acacia
(c) Cladode is seen in Asperagus.
(d) All the above statements are not correct.
Answer:
(d) All the above statements are not correct.

28. Choose the correct statement.
(a) In desert plants the root system is not well developed.
(b) In xerophytes, the stems and leaves are covered with wax coating.
(c) In xerophytes, the vascular bundles are not well developed.
(d) None of the above.
Answer:
(b) In xerophytes, the stems and leaves are covered with a wax coating.

29. Find out the incorrect statement.
(a) Cuscuta is a total stem parasite
(b) Balanophora is a hemi parasite
(c) Rafflesia is a total root parasite
(d) Viscum is a partial stem parasite
Answer:
(b) Balanophora is a hemi parasite

30. Which of the following statement is correct?
(a) The nitrogen filing bacteria Rhizobium is present in the coralloid roots in cycas.
(b) The cyanobacterium Anabaena is present in the root nodules of leguminous plants,
(c) The interaction of water fern Azolla and nitrogen-fixing cyanobacterium is an example of mutualism.
(d) None of the above.
Answer:
(c) The interaction of water fern Azolla and nitrogen-fixing cyanobacterium is an example of mutualism.

Students get through the TN Board 12th Bio Botany Important Questions Chapter 5 Plant Tissue Culture which is useful for their exam preparation.

TN State Board 12th Bio Botany Important Questions Chapter 5 Plant Tissue Culture

Very short answer questions

Question 1.
Mention any two Indian scientists who worked on the tissue culture of plants.
Answer:

1. Kanta
2. Maheswari

Question 2.
Define Totipotency.
Answer:
Totipotency is defined as the genetic potential of a plant cell to give rise to a complete individual plant in a nutrient medium.

Question 3.
What is meant by explant?
Answer:
The explant is the tissue taken from a selected plant for tissue culture under invitro condition to establish a new plant.

Question 4.
Define Sterilization.
Answer:
Sterilization refers to a technique used to get rid of microbial contamination by bacteria and fungi in tissue culture practice.

Question 5.
Define Embryogenesis.
Answer:
Embryogenesis is the process through which the callus cells undergo differentiation to produce somatic embryos called Embryoids.

Question 6.
Name any two vitamins used in plant tissue culture works.
Answer:

1. Nicotinic acid
2. Pyridoxin HCl

Question 7.
Define Organogenesis.
Answer:
Organogenesis is defined as a process of the morphological changes in callus cells leading to the formation of shoot and roots.

Question 8.
What is meant by ‘Synthetic seeds’?
Answer:
Synthetic or artificial seeds are developed, from somatic embryos, which are encapsulated by inert materials like agarose and sodium alginate.

Question 9.
What is Gene Bank?
Answer:
A Gene bank is a place or laboratory, where the genetic material or germplasm of elite breeding lines of plants are stored for safe maintenance. This germplasm can be used for future use in research and revival of the plant.

Question 10.
What do you understand by intellectual property rights (IPR)?
Answer:
Intellectual Property Right is the right of property, which involves human intellect.
It consists of copyrights, patents, and trademarks.

Question 11.
Define Biosafety.
Answer:
Biosafety is defined as a procedure through which the prevention of large-scale loss of biological integrity focusing both on ecology and human health due to the advancement and application of Biotechnology.

Question 12.
Name any two apex bodies for the implementation of biosafety guidelines.
Answer:

1. Institutional Biosafety Committees (IBSCs)
2. Genetic Engineering Approval Committee (GEAC)

Short answer questions

Question 1.
Explain the term dedifferentiation.
Answer:
Dedifferentiation is the phenomenon of the revision of mature plant cells to the meristematic state and they actively divide, forming the callus in the nutrient medium. The phenomena of redifferentiation and dedifferentiation are the inherent property of plant cells or tissues. This property is described as totipotency.

Question 2.
How do you sterilize a plant tissue culture room?
Answer:
The tissue culture room sterilization starts with washing of floor and walls with detergent water and then wiped with 2% sodium hypochlorite or 95% ethanol. The cabinet of the laminar airflow chamber and the working space is wiped with 95% ethanol and subjected to uv radiation for 15 minutes, in order to get rid of all microbes in the culture room.

Question 3.
Distinguish between differentiation and Redifferentiation.
Answer:

Differentiation	Redifferentiation
Differentiation is a process of biochemical and structural changes in cells, leading to specialized form to perform a particular function.	Redifferentiation is the process through which the differentiated cells transform into another type of cells. Formation of whole plant from callus is the example of redifferentiation.

Question 4.
How do you induce callus formation, in the nutrient medium?
Answer:
In sterilized MS nutrient medium, the explant of size 1-2 cm sterile segment of leaf, stem, tuber, or root is placed. The nutrient medium is supplemented with growth hormones like auxins. The explants in the medium are ” incubated at 25 ± 2°C in the culture chamber ‘ with alternate light and dark period of 12 hrs to induce cell division. The cells on the upper surface of the explant start dividing to form a callus, which is a mass of unorganized cells or tissues, grown invitro in a culture medium.

Question 5.
Explain the process of hardening.
Answer:
The plantlets developed in the culture room need hardening to withstand the changes in the field. Therefore they are transferred to a greenhouse or hardening chamber. After some time they are transferred to normal environmental conditions. Hardening is the process in which the plantlets developed in vitro conditions are slowly exposed to diffused light for acclimatization so as to enable them to grow under normal field conditions.

Question 6.
Describe the method of Isolation of protoplast.
Answer:
Protoplasts are the plant cells without a cell wall, encircled by a cell membrane.
The small plant bits or tissue-like leaf tissue are used to prepare protoplasts. The leaf bits are immersed in 0.5% microzyme or Onizuka cellulase enzymes dissolved in 13% sorbitol or mannitol at pH 5.4. It is then kept for overnight incubation at 25°C. The protoplasts are obtained by gentle teasing of cells. The protoplasts are transferred to 20% sucrose solution in order to retain their viability. The pure protoplasts are obtained by centrifugation, which removes all debris of cell walls.

Question 7.
Give the different types of metabolites their sources and uses.
Answer:

Secondary metabolites	Plant source	Uses
Digoxin	Digitalis purpuria	Cardiac tonic
Codeine	Papaver sominiferum	Analgesic
Capsaicin	Capsicum annum	Rheumatic pain treatment
Vincristine	Catharanthus roseus	Anti-carcinogenic
Quinine	Cinchona officinalis	Antimalarial

Question 8.
Distinguish between Somaclonal variation and Gametoclonal variations.
Answer:

Somaclonal variation	Gametoclonal variations
The variations found in leaf, stem, root, tuber or propagule of the plants regenerated in invitro conditions are named as somaclonal variations.	The variations found in gametes and gametophytes of plants regenerated in vitro gametic origin are known as gametoclonal variation.

Long answer questions

Question 1.
Describe the production of secondary metabolites in plants.
Answer:
The secondary metabolites like alkaloids, flavonoids, terpenoids, phenolic compounds and recombinant proteins are produced through cell suspension culture. The secondary metabolites are not required by the plant. But they are produced in the plant as ‘by product’ of cell metabolism.
For commercial production of secondary metabolites, the bioreactors are used for scaling up the production by means of automation. Biotransformation, elicitation, and immobilization are strategies used, making cell suspension culture more efficient in the production of secondary metabolites. The examples of industrially producing important plant secondary metabolites are listed in the table.
…. For table refer to page 78, Q.No. 7.

Question 2.
Describe the important steps involved in the micropropagation of the banana plant.
Answer:

Question 3.
What are the advantages of artificial seeds?
Answer:
Artificial seeds are produced by encapsulation of embryoids with sodium alginate or agrose. They have many advantages over true seeds. These are as follows.

1. At a time millions of artificial seeds can be prepared at low cost.
2. Genetically engineered plants with desirable characteristics can easily be made through this method.
3. The genotype of a plant can easily be tested.
4. Using the cryopreservation technique artificial seeds can be stored easily for a long time.
5. The artificial seed produces identical plants.
6. As the growth of the artificial seed is faster with shortened life cycle the dormancy period of these seeds is considerably reduced.

Question 4.
What are the main components of Intellectual Property Right (IPR).
Answer:
The primary components of IPR include copyright, patents, and trademark. Other types of rights include trade secrets, publicity rights, moral rights, and the right against unfair competition.

1. In biotechnology, the transformed microorganisms and plants, and technologies for the production of commercial products are the exclusive property of the discoverer.
2. The discoverer has the full right of the property and others cannot use it without legal permission.
3. The right of the discoverer should be protected by framing laws by a country.
4. The IPR is protected by different ways like copyrights, patents, trade secrets, and trademarks.

Question 5.
What are the applications of plant tissue culture?
Answer:
Plant tissue culture has many applications:

1. Somatic hybridization provides an opportunity for the production of improved hybrids in plants.
   Somatic embryoids help in the production of artificial seeds, which help in the conservation of plant biodiversity.
2. The disease-resistant plants can be produced by the meristem and shoot tip culture technique.
3. Stress tolerant plants such as herbicide-tolerant and heat resistant plants can also be produced.
4. Large-scale propagation of tree plants and cultivable plants can be produced through micropropagation throughout the year.
5. The cell suspension culture provides the production of secondary metabolites in plants, which are utilized in pharmaceutical, cosmetic, and food industries.

Question 6.
Write the protocol for virus-free meristem tip culture.
Answer:

Choose the correct answer:

1. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
Answer:
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

2. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(d) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
Answer:
(c) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)

3. Match the following:

(a) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
Answer:
(a) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)

4. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
Answer:
(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)

5. Somatic embryogenesis is now reported in:
(a) Mango
(b) Potato
(c) Rice
(d) Cucumber
Answer:
(c) Rice

6. Organogenesis can be induced by:
(a) Glycine
(b) Vitamin
(c) Aspartic acid
(d) Auxin
Answer:
(d) Auxin

7. The phenomenon in which the mature cells are transformed into meristamatic state is called:
(a) Differentiation
(b) Dedifferentiation
(c) Redifferentiation
(d) Totipotency
Answer:
(b) Dedifferentiation

8. Cryopreservation is a process of preserving plant materials by cooling to very low temperature of:
(a) -190°C
(b) -195°C
(c) -185°C
(d) -20°C
Answer:
(b) -195°C

9. Virus free plants are produced by a method called:
(a) Protoplast culture
(b) Organ culture
(c) Apical meristem culture
(d) Tissue culture
Answer:
(c) Apical meristem culture

10. Choose the odd man out:
(a) Carlson
(b) Chiton
(c) Kanta
(d) T.H Morgan
Answer:
(d) T.H Morgan

11. Find the odd one out:
(a) Magnesium sulfate
(b) Auxin
(c) Nicotinic acid
(d) Potassium nitrate
Answer:
(b) Auxin

12. Identify the odd one out.
(a) Artificial seed
(b) Embryoids
(c) Somatic hybrid
(d) Plantlets
Answer:
(c) Somatic hybrid

13. Choose the odd one out.
(a) Agar
(b) Kinetin
(c) Myo-inositol
(d) Glucose
Answer:
(a) Agar

14. Indicate the odd one out:
(a) Capsicum annum
(b) Catharanthus roseus
(c) Oryza sativa
(d) Cinchona officinalis
Answer:
(c) Oryza sativa

15. Choose the correct pair:
(a) Digoxin – Analgesic
(b) Codeine – Cardiac tonic
(c) Quinine – Antimalarial
(d) Vincristine – Antibacterial
Answer:
(c) Quinine – Antimalarial

16. Which of the following is the incorrect pair?
(a) Cell culture – Liquid medium
(b) Somatic Hybrid – Fusion of protoplast
(c) Protoplast culture – Ms liquid medium
(d) Organ culture – Polyethylene glycol
Answer:
(d) Organ culture – Polyethylene glycol

17. Choose the correct pair:
(a) Micropropagation – Coconut plant
(b) Secondary metabolites – Cosmetics
(c) Sonaclonal – Heat resistant
(d) Gametoclonal – Herbicide-resistant
Answer:
(b) Secondary metabolites – Cosmetics

18. Assertion and Reason:
Assertion: Artificial seeds are produced by using embryoids obtained through in-vitro culture.
Reason: They may be derived from single cells from any part of the plant.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is correct.
(d) Both Assertion and Reason are not correct.
Answer:
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.

19. Assertion: MS nutrient medium is commonly used in tissue culture.
Reason: It has carbon sources, with suitable vitamins and hormones essential for plant growth.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is correct.
(d) Both Assertion and Reason are not correct.
Answer:
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.

20. Assertion: The callus cells undergo redifferentiation and produce somatic embryos.
Reason: The embryoids are sub-cultured to produce plantlets.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is correct.
(d) Both Assertion and Reason are not correct.
Answer:
(c) Assertion is not correct, Reason is correct.

21. Assertion: Quinine is produced by the cells of Capsicum annum through in-vitro culture.
Reason: Quinine is used as an anticarcinogenic agent.
(a) Assertion and Reason are correct, Reason is the correct explanation of Assertion.
(b) Assertion and Reason are correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is correct.
(d) Both Assertion and Reason are not correct.
Answer:
(d) Both Assertion and Reason are not correct.

22. Which of the following statement is correct?
(a) The process of production of metabolites can be scaled up and automated using bioreactors.
(b) Biosynthesis of indole alkaloids is carried out by Capsicum annum.
(c) Biosynthesis of indole alkaloids is carried out by Vinca rosea.
(d) None of the above.
Answer:
(a) The process of production of metabolites can be scaled up and automated using bioreactors.

23. Choose the incorrect statement.
(a) Improved hybrid plants can be produced through somatic hybridization.
(b) Somatic hybrids can be encapsulated into synthetic seeds.
(c) Production of disease-resistant plants can be carried out by cell suspension culture.
(d) Production of metabolites through cell suspension culture.
Answer:
(c) Production of disease-resistant plants can be carried out by cell suspension culture.

24. Find out the correct statement.
(a) Glycerol is used as a cryopreservation agent in the cryopreservation of plant material.
(b) Glycerol is used as a protective agent in the cryopreservation of plant material.
(c) Auxin is used as a cryoprotectant in the cryopreservation of plant materials.
(d) None of the above.
Answer:
(b) Glycerol is used as a protective agent in the cryopreservation of plant material.

25. Choose the incorrect statement.
(a) Vasil and Hildebrandt developed in-vitro production of haploid embryos from the anthers of Datura.
(b) Guha and Maheshwari produced calli and free cells in tissue culture of Tradeseantia reflex.
(c) Carlson regenerated tobacco plants from isolated mesophyll protoplasts.
(d) All the above statements are correct.
Answer:
(d) All the above statements are correct.

Students get through the TN Board 12th Bio Botany Important Questions Chapter 4 Principles and Processes of Biotechnology which is useful for their exam preparation.

TN State Board 12th Bio Botany Important Questions Chapter 4 Principles and Processes of Biotechnology

Very short answer questions

Question 1.
Name the scientists who first produced monoclonal antibodies.
Answer:

1. Kohler
2. Milstein

Question 2.
Define traditional Biotechnology.
Answer:
Traditional biotechnology is the process developed by our ancestors in the kitchen by using fermentation bacteria. Eg. Idli, Dosa, Curd, Nan, etc.

Question 3.
Name any two commercial products produced through fermentation technology.
Answer:

1. Bread
2. Wine

Question 4.
Mention any two single-cell proteins.
Answer:

1. Spirulina
2. Chlorella

Question 5.
Define conventional recombination.
Answer:
Conventional recombination is a process. which involves the exchange of genes between homologous chromosomes during meiosis.

Question 6.
What is meant by polymerase chain reaction (PCR)?
Answer:
The polymerase chain reaction is a common laboratory technique used to make a million copies of a particular region of DNA.

Question 7.
What are the basic tools for genetic engineering?
Answer:
The basic tools of genetic engineering include enzymes, vectors, and host organisms.

Question 8.
Define Vectors.
Answer:
Vectors are defined as small DNA molecules capable of self-replication and are used as carriers and transporter of DNA fragments, inserted into them for cloning.

Question 9.
Define Biopiracy.
Answer:
Biopiracy is defined as the manipulation of intellectual property rights laws by corporations to gain exclusive control over national genetic resources.

Question 10.
What is a plasmid?
Answer:
Plasmids are extrachromosomal, self-replicating ds circular DNA molecules, found in bacterial cells in addition to chromosomal DNA.

Question 11.
Explain Chemical mediated gene transfer.
Answer:
The uptake of DNA into the plant protoplast is induced by some chemicals like polyethylene glycol (PEG) and dextran sulphate. This type of gene transfer is called chemical-mediated gene transfer.

Question 12.
What is an antibiotic gene marker?
Answer:
An antibiotic gene marker is a gene, which is coded for a protein, that provides the cells to resist to a particular antibiotic.

Question 13.
What is meant by ELISA?
Answer:
ELISA otherwise known as Enzyme-Linked Immuno Sorbent Assay is a diagnostic tool for the identification of pathogen species by using antibodies and diagnostic agents.

Question 14.
Define Transfection.
Answer:
Transfection is a technique of introduction of foreign nucleic acids into cells using non-viral methods.

Question 15.
What is a transgenic plant?
Answer:
A transgenic plant is a genetically modified plant, which contains a novel DNA introduced into its genome.

Question 16.
Name any two genetically modified food.
Answer:

1. Bt Brinjal
2. Flavrsavr Tomato

Question 17.
Define Biopharming.
Answer:
Biopharming has otherwise known as molecular pharming in which the use of genetically modified transgenic plants to produce pharmaceutical substances.

Question 18.
What is MycOremediation?
Answer:
Mycoremediation is a technique of reducing environmental pollutants using fungi.

Question 19.
What is Composting?
Answer:
Composting is a process in which solid waste is converted into useful manure by the use of microbes or Earthworms.

Short answer questions

Question 1.
What is a bioreactor?
Answer:
A bioreactor or fermentor is a designed vessel or container for the fermentation process. It provides an optimum environment in which microorganisms or their enzymes interact with a substrate to produce the required product. The environmental conditions like aeration, agitation, temperature, and pH are controlled in the fermentor for optimum production of a product.

Question 2.
Mention any three bioconversion done by fermenting microbes.
Answer:
The fermenting microbes are capable of producing valuable products, which as follows:

1. Conversion of ethanol to acetic acid (Vinegar).
2. Conversion of isopropanol to acetone.
3. Conversion of sterols to steroids.

Question 3.
Name any three fungi used in the production of SCP?
Answer:

1. Agaricus campestris
2. Saccharomyces cerevisiae (yeast)
3. Candida utilize.

Question 4.
Explain the types of restriction enzymes?
Answer:
A restriction enzyme is an enzyme, which is able to cut DNA molecules into fragments at desired sites within the molecule known as restriction sites. They are classified into Exonucleases and Endonucleases based on their mode of action.

1. Endonucleases are the enzymes responsible for removing one nucleotide at a time from the end of a DNA molecule.
   Eg: Bal 31, Exonuclease III
2. Endonucleases are enzymes that break the internal phosphodiester bonds within DNA molecules.
   Eg: Hind II, EcoRI, Pvul, BamHI, TaqI.

Question 5.
Give a schematic diagram of Alkaline Phosphate action.
Answer:

Question 6.
What is meant by the walking gene? Explain it briefly.
Answer:
Walking genes or jumping genes are DNA sequences able to insert themselves at a new location in the genome without having any sequence relationship with the target locus. They are also called transposons, which is well suited in E.coli studies. They are used as genetic tools for the analysis of gene and protein functions, which are responsible for phenotypic expression on the host cell.

Question 7.
Explain briefly about Biolistics.
Answer:
Biolistics is a process in which minute gold or tungsten particles (1-3 pm) are coated with foreign DNA on the surface. These particles coated with DNA are bombarded onto the target tissue or cells using a particle gun or gene gun. The cells or tissue with bombed particles are cultured in a selected medium to regenerate plants from the transformed cell.

Question 8.
Explain the technique of Northern Blot.
Answer:
Alwin et al in 1979 devised this technique, as RNA is not binding cellulose nitrate, the chemical used in Southern blot. In this technique, RNA bands are transferred from the agarose gel into nitrocellulose filter paper. This technique of transfer of RNA from gel to special filter paper is known as Northern. Blotting hybridization. Amino Benzyloxy methyl paper of 540 what man paper is used in Northern Blot.

Question 9.
What are the advantages of Herbicide ” Tolerant crops?
Answer:

1. Weed control in agriculture improves crop yields.
2. The cultivation of these crops reduces the spray of herbicide.
3. It reduces competition between crop plants and weeds.
4. The use of low toxicity compound which do not remain active in the soil.
5. It helps to conserve soil structure and microbes in the soil.

Question 10.
List the advantages of Bt cotton.
Answer:

1. Due to effective control of bollworms, the yield of cotton is increased.
2. Reduction in the use of insecticide in the cultivation of Bt cotton.
3. It causes a potential reduction in the cost of cultivation.

Question 11.
List the examples of Bioremediation technologies.
Answer:

1. Phytoremediation
2. Mycoremediation
3. Bioventing
4. Bioleaching
5. Bioaugmentation
6. Composting
7. Rhizofiltration
8. Rhizostimulation

Question 12.
Distinguish between Rhizofiltration and Rhizostimulation.
Answer:

Rhizofiltration	Rhizostimulation
Rhizofiltration is the uptake of metals or degradation of organic compounds using rhizosphere microorganisms.	Rhizostimulation is a process, in which the stimulation of plant growth by the rhizosphere which provides better growth condition or reduction in toxic material.

Long answer questions

Question 1.
What is the importance of fermentation technology?
Answer:
Fermentation technology is a kitchen technology developed by our ancestors, using natural fermentation bacteria. It is a metabolic process in which organic molecules such as glucose are converted into alcohols, acids or gases like methane. The conversion takes place in the absence of oxygen or any electron transport chain. In 1856 Lois Pasteur demonstrated fermentation using yeast and this practice is called zymology. Certain types of bacteria and fungi, which thrive without oxygen can also be involved in fermentation.
The process of fermentation is employed in food and beverages industries, which are involved in the conversion of sugar into ethanol to produce alcoholic beverages. The production of CO₂ by yeast can be used in the leavening of bread. The production of organic acids can preserve and flavor vegetables and dairy products.

Question 2.
Describe the steps involved in recombinant DNA technology.
Answer:
The following are the steps involved in recombinant DNA technology.

1. Isolation of a DNA fragment having a gene of interest that needs to be cloned. This DNA fragment is known as an insert.
2. The insertion of the DNA fragment into a carrier molecule called the vector produces recombinant DNA (rDNA) molecule. The vector molecule self-replicate within the host cell.
3. The transformed host cells that carry the rDNA are selected and allowed to multiply resulting in the multiplication of the rDNA molecule.
4. Thus the entire process generates a large amount of rDNA or a large amount of protein expressed by the insert.
5. The desired gene is multiplied by the PCR technique if vectors are not involved. The microinjection or shotgun methods are employed to transfer the multiple copies of DNA into the host cell protoplasm.
   

Question 3.
Explain the technique of Agrobacterium-mediated gene transfer with a suitable diagram.
Answer:
Vector mediated gene transfer is the indirect type of gene transfer in which a placed vector helps in gene transfer. The T₁ plasmid from Agrobacterium tumefacient has been used extensively in vector-based gene transfer. T₁ plasmid (Tumor inducing) a portion of which is T-DNA is a large size plasmid. When transferred into to plant genome of the infected cell and cause plant tumors. (Crown gall). This bacterium has the natural ability to transfer the T-DNA region of its plasmid into the plant genome upon infection of cells at the wound site and this is called natural genetic engineering of plants.

Question 4.
Explain the technique of biological hydrogen production by algae with the aid of a suitable diagram.
Answer:
Photobiological splitting of H₂O is the technique used in the biological production of Hydrogen using algae. The algae, Chlamydomonas reinhardtii releases oxygen in normal photosynthesis. When it is deprived of sulfur, it switches to the production of hydrogen during photosynthesis and the electrons are transported to ferredoxins [F]- hydrogenase enzymes combine them into the production of hydrogen gas.

Question 5.
Bring out the differences between blotting techniques.
Answer:
There are three types of blotting techniques and the differences are tabulated below:

Question 6.
Draw the schematic diagram of steps involved in the Southern blotting technique.
Answer:

Choose the correct answer:

1. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(iii); (s)-(a)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
Answer:
(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)

2. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(ii); (q)-(in); (r)-(iv); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
Answer:
(b) (p)-(ii); (q)-(in); (r)-(iv); (s)-(i)

3. Match the following: (Products of Biotechnology)


(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(c) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)

4. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(ii); (q)-(iii); (r)-(iv); (s)-(i)
Answer:
(d) (p)-(ii); (q)-(iii); (r)-(iv); (s)-(i)

5. Match the following:

(a) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(c) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(b) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

6. Curd forming is a process of:
(a) Biodegradation
(b) Fermentation
(c) Sterilization
(d) Bioremediation
Answer:
(b) Fermentation

7. The technique of gene transfer using a pulse high voltage is known as:
(a) Liposome mediated transfer
(b) Electromagnetic transfer
(c) Electrophoration
(d) Biolistic
Answer:
(c) Electrophoration

8. The chemical used in southern blotting is:
(a) B galactoside
(b) Nitrophenol
(c) Nitrocellulose
(d) Benzyloxymethyl
Answer:
(c) Nitrocellulose

9. Bt Brinjal is produced by inserting a crystal protein gene from:
(a) Bacillus hyphae
(b) Streptomyces hygroscopic
(c) Streptomyces grises
(d) Bacillus thuringiensis
Answer:
(d) Bacillus thuringiensis

10. Addition of selected microbes to speed up degradation process called:
(a) Bioleaching
(b) Bioaugmentation
(c) Biofilteration
(d) Bioventing
Answer:
(b) Bioaugmentation

11. Choose the odd man out:
(a) Ethanol
(b) Acetic acid
(c) Vitamins
(d) Citric acid
Answer:
(c) Vitamins

12. Indicate the odd one out:
(a) Fermentation
(b) r-DNA technology
(c) Bioconversion
(d) SCP production
Answer:
(b) r-DNA technology

13. Find out the odd one:
(a) Methylophilus methylotropus
(b) Cellulomonas
(c) Alcaligenes
(d) Candida utilis
Answer:
(d) Candida utilis

14. Choose the odd one:
(a) Hind III
(b) CoIEl
(c) EcoRI
(d) BamHI
Answer:
(b) CoIEl

15. Indicate the odd one:
(a) Micro injection
(b) Electroporation
(c) Biolistic
(d) Western blot
Answer:
(d) Western blot

16. Chooose the correct pair.
(a) Streptomyces grises – Tetracycline
(b) Streptomyces nodosus – Amphotericin-B
(c) Streptomyces aureofacins – Penicillin
(d) Penicillin chryosogenum – Streptomycin
Answer:
(b) Streptomyces nodosus – Amphotericin-B

17. Find out the incorrect pair.
(a) Genetic Engineering – r-DNA technology
(b) Restriction Enzyme – Endonuclease
(c) DNA ligase – Clevage enzyme
(d) Vector – Plasmid
Answer:
(c) DNA ligase – Clevage enzyme

18. Indicate the correct pair:
(a) Ti plasmid – Agrobacterhim tumifaciens
(b) Walking gene – Expression vector
(c) Gene transfer – Nitrocellulose
(d) Liposome – artificial glycolipid vesicle
Answer:
(a) Ti plasmid – Agrobacterhim tumifaciens

19. Choose the incorrect pair:
(a) Bt cotton – GM food
(b) Basta – Herbicide tolerant
(c) Bt Brinjal – Delhi university
(d) DMH-II – Transgenic mustard
Answer:
(c) Bt Brinjal – Delhi university

20. Indicate the correct pair:
(a) Phytoremediation – use of algae
(b) Mycoremediation – use of Fungi
(c) Bioventing – use of plants
(d) Bioleaching – use of earthworm
Answer:
(b) Mycoremediation – use of Fungi

21. Assertion: Traditional Biotechnology is the kitchen technology by using fermenting bacteria.
Reason There is no scientific validation of these kitchen technologies.
(a) Both Assertion and Reason are true. But 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:
(c) Assertion is true, but Reason is false.

22. Assertion: Secondary metabolites are those i which are required for the vital life process of microbes.
Reason: They are the vital compounds required for the growth of microbes.
(a) Both Assertion and Reason are true. But Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are true. But Reason is not correct explanation of Assertion.
(c) Assertion is true, but Reason is false.
(d) Both Assertion and Reason are false.
Answer:
(d) Both Assertion and Reason are false.

23. Assertion: The single-cell protein forms an important source of food.
Reason: Because they contain protein, carbohydrates, fats, vitamins and minerals.
(a) Both Assertion and Reason are true. But 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. But Reason is the correct explanation of Assertion.

24. Assertion (A): The restriction enzymes are called as molecular scissors.
Reason (R): They cleave the DNA molecules into fragments at specific recognition sites.
(a) Both Assertion and Reason are true. But 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. But Reason is the correct explanation of Assertion.

25. Assertion (A): Polylactic acid (PLA) is a biodegradable and bioactive thermoplastic.
Reason (R): It is an aliphatic polyester derived from renewable resources.
(a) Both Assertion and Reason are true. But 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:
(b) Both Assertion and Reason are true. But Reason is not the correct explanation of Assertion.

26. Which of the following statement is correct?
(a) Liposomes are the artificial lipoprotein vesicles vised for gene transfer.
(b) Liposomes are the artificial glycoprotein vesicles used for gene transfer.
(c) Liposomes are the artificial phospholipid vesicles used for gene transfer.
(d) None of the above.
Answer:
(c) Liposomes are the artificial phospholipid vesicles used for gene transfer.

27. Choose the incorrect statement.
(a) The bacterium Strepfpmyces nodosus produces the antibiotic Amphotericin-B.
Ethanol is the primary metabolite produced by microorganisms.
(c) Vitamins are the secondary metabolites.
(d) All the above statements are not correct.
Answer:
(d) All the above statements are not correct.

28. Indicate the correct statement:
(a) Humulin is the first pharmaceutical product of rDNA technology for human use.
(b) The first transgenic animal, Dolly was developed by rDNA technology.
(c) First crop plant genome was sequenced in wheat.
(d) Sir Robert G.Edwards grew stem cells in the laboratory.
Answer:
(a) Humulin is the first pharmaceutical product of rDNA technology for human use.

29. Which of the following statement is wrong:
(a) Enzymes are biosensors in the processing industry.
(b) Biomass is the bulk production of single-cell organisms.
(c) Process engineering is the tool of biotechnology used for effluent treatment.
(d) All the above statements are wrong.
Answer:
(d) All the above statements are wrong.

30. Choose the correct statement.
(a) Composting is the process of recycling solid waste by microbes.
(b) Composting is the process of recycling solid waste by plants.
(c) Bioleaching is the use of plants to recover metal pollutants.
(d) Rhizofiltration is the process of water purification.
Answer:
(a) Composting is the process of recycling solid waste by microbes.

Students get through the TN Board 12th Bio Botany Important Questions Chapter 3 Chromosomal Basis of Inheritance which is useful for their exam preparation.

TN State Board 12th Bio Botany Important Questions Chapter 3 Chromosomal Basis of Inheritance

Very short answer questions

Question 1.
Name the scientists, who proposed the theory of chromosomal inheritance.
Answer:

1. T. Boveri
2. W.S.Sutton

Question 2.
Write down the chromosome numbers of j rice and potato.
Answer:

1. Rice – 24 Nos

Question 3.
Define fossil genes.
Answer:
Fossil genes are junk DNA made up of pseudogenes, which lost their ability to make proteins.

Question 4.
Define Linkage.
Answer:
Linkage is the type of tendency of the genes to stay together during the separation of chromosomes.

Question 5.
Explain synapsis.
Answer:
Synapsis is a phenomenon in which the homologous chromosomes are aligned side by side resulting in a pairing of a pair of homologous chromosomes.

Question 6.
What is meant Chiasmata?
Answer:
Chiasmata are the points of contact between non-sister chromatids of homologous chromosomes, forming X- shaped structures.

Question 7.
Define Terminalisation.
Answer:
Terminalisation is a process, in which the chiasma starts to move towards the terminal end of chromatids, after crossing over.

Question 8.
Define Recombination frequency (RF).
Answer:
Recombination frequency is the percentage of recombinant progeny in a cross.

Question 9.
What is meant by genetic mapping?
Answer:
Genetic mapping is the diagrammatic representation of the position of genes and related distance between the adjacent genes.

Question 10.
Does environment play a role in sex determination in plants? Explain it with an example.
Answer:
Yes. The plants grown under favorable conditions develop as female in the Horsetail plant whereas the plants under unfavorable conditions develop into males.

Question 11.
What are the two types of mutation?
Answer:
The broad types of mutation are point mutation and chromosomal mutation.

Question 12.
Define mutagen.
Answer:
Mutagens are agents which are responsible for changes in the genetic material.

Question 13.
Mention any two physical mutagens.
Answer:

1. X-ray
2. U.V – ray

Question 14.
What is Rharbati Sonora?
Answer:
Sharbati Sonora is a mutant variety of wheat.
This is developed by Dr. M.S.Swaminathan ! and his team, by irradiating the Mexican I variety of wheat (Sonora 64) with gamma rays.

Question 15.
Define hypoploidy.
Answer:
Hypoploidy is defined as a process in which the loss of one or more chromosomes from the diploid set of chromosomes in the cell takes place.

Question 16.
Name the type of polyploidy.
Answer:
The types of polyploidy are autopolyploidy and allopolyploidy.

Question 17.
Name the two organisms, in which the process of deletion is demonstrated.
Answer:

1. Maize
2. Drosophila

Question 18.
What are the two types of inversion?
Answer:
The two types of inversion are paracentric and pericentric inversion.

Question 19.
What has displaced duplication?
Answer:
Displaced duplication is a phenomenon in which the duplicated segment of a chromosome is located in the same chromosome, but away from the normal segment.

Question 20.
Mention any two chemical mutagens.
Answer:

1. Ethyl Methane Sulphonate (EMS).
2. Formaldehyde.

Short answer questions

Question 1.
Distinguish between Mendelian factors and Chromosome behavior.
Answer:

Mendelian factors	Chromosome behaviour
Alleles of a factor occur in pairs.	Chromosomes occur in pairs.
During gamete formation, alleles of a factor separate from each other.	During meiosis the homologous chromosomes separate.
Mendelian factors assort independently.	Linked genes in the same chromosome normally do not assort independently, but paired chromosomes can separate independently.

Question 2.
When a male heterozygous Drosophila is crossed with. double recessive female, only parental phenotype individuals are produced – Justify.
Answer:

1. The crossing over is absent in male Drosophila.
2. The recombination of alleles does not occur.
3. The particular genes are linked and hence they are not assorted independently.

Question 3.
Explain the three types of synapsis.
Answer:
The three types of synapsis are as follows:

1. Procentric synapsis: Pairing starts from the middle of the chromosome.
2. Proterminal synapsis: Pairing starts from the telomeres.
3. Random synapsis Pairing may start from anywhere in the chromosome.

Question 4.
List out any three importance of cross over.
Answer:

1. Experiments on crossing over reveal that genes are placed linearly on the chromosomes. .
2. The frequency of crossing over helps is a genetic map.
3. The nature and mechanism of gene action can be understood through studies on crossing over.

Question 5.
Write down the uses of genetic mapping.
Answer:

1. Dihybrid and trihybrid results can easily be predicted.
2. It is used to determine the order of genes on the chromosome.
3. It is useful to identify the locus of a gene and calculate the distance between genes.
4. The overall genetic complexity of an organism can be understood by genetic mapping.

Question 6.
State the principles of sex determination in Melandrium album.
Answer:

1. X chromosome specifies femaleness.
2. Maleness is determined by the Y chromosome.
3. X and Y show different segments of chromosomes.

Question 7.
Explain comutagens with an example.
Answer:
Comutagens are compounds that enhance the effects of known mutagen. They do not have mutagenic properties.
Eg: The damage caused by hydrogen peroxide can be increased by Ascorbic acid.

Question 8.
Distinguish between Gene mutation and Chromosomal Mutation.
Answer:

Gene Mutation	Chromosomal Mutation
Gene mutations are the genetic changes within a gene.	Chromosomal mutations are the changes to chromosome region or number of chromosomes.
Gene mutation cannot be detectable microscopically.	Chromosomal mutations can be detected by microscopic examination.

Question 9.
Explain chromosomal mutation with an example.
Answer:
Chromosomal mutation or chromosomal aberration is the process in which the genome of an organism can be altered on a large scale by modifying the chromosome structure or by altering the number of chromosomes.
Eg: This type of mutation has been noticed in Datura, Nicotiana, Pisum, and Oenothera.

Question 10.
Distinguish between autopolyploidy and allopolyploidy.
Answer:

Autopolyploidy	Allopolyploidy
Autopolyploidy is the condition in which an organism posses two or more than two haploid sets of chromosomes, derived from within the same species. Eg: Tomato, apple etc.	Allopolyploidy is the condition in which an organism possesses two or more sets of chromosomes derived from two different species. Eg: Radish, Cabbage etc.

Question 11.
Give a diagrammatic representation of paracentric and pericentric inversion of chromosomes.
Answer:

Question 12.
Differentiate between Aneuploidy and Euploidy.
Answer:

Aneuploidy	Euploidy
Aneuploidy involves individual chromosomes within a diploid set.	Euploidy involves entire set of chromosomes.
Diploid number is altered either by addition or by deletion of one or more chromosomes.	Euploidy is the condition in which the organism possess one or more basic sets of chromosomes.

Long answer questions

Question 1.
Given an account of the historic development of chromosome theory.
Answer:
The important scientific findings on the chromosome theory of inheritance are given below:

1. Wilhelm Roux in 1883 found out that chromosomes of a cell are responsible for transferring heredity.
2. Montgomery in 1901 suggested the occurrence of distinct pairs of chromosomes. He also postulated that during meiosis maternal chromosomes pair with paternal chromosomes.
3. T.Boveri in 1902 confirmed that genetic determiners are present in the chromosomes and suggested the chromosomal theory of inheritance.
4. W.S.Sutton in 1902 recognized a similarity between the mendelian factors and the behavior of chromosomes during gamete formation.
5. Sutton and Boveri in 1903 independently proposed the chromosome theory of inheritance.

Question 2.
Explain the complete linkage of genes in maize with a diagram.
Answer:
The phenomenon of incomplete linkage was first reported by Hutchinson in maize. The chances of separation of genes are possible if the two linked genes are placed sufficiently apart. As a result potential and non-potential combinations are noticed. These linked genes show some crossing over and this phenomenon is called incomplete linkage.

Question 3.
Give the schematic representation of the eye color inheritance in Drosophila.
Answer:

Question 4.
Draw the schematic diagram of types of crossing over with its Recombination
Answer:

Question 5.
Describe the types of point mutations.
Answer:
Point mutation refers to the changes in single base pairs of DNA or in a small number of adjacent base pairs. There are two types of point mutations namely base-pair substitution and base-pair insertion or deletion.
the substitution of base pair in the DNA is the type of mutation in which one base pair is replaced by another base pair. This can be divided into two subtypes namely transition and transversion type.
Addition or deletion mutations in which addition or deletion of nucleotide pair takes place. This is called either base pair addition or base pair deletion. They are collectively termed indel mutations.
Substitution or the indel mutations cause changes in the translation. Based on this, the mutations are classified as silent mutation, missense mutation, nonsense mutation, and frameshift mutation.
Silent mutation or synonymous mutation: It is a type of mutation in which changes in one codon for an amino acid into another codon for that same amino acid to occur.
In missense or non-synonymous mutation, the codon of one amino acid is changed into a codon of another amino acid.
A nonsense mutation is a DNA mutation in which the change of codon for one amino acid is modified into a termination or stop codon.
In frameshift mutations, the addition or deletion of single base pair of DNA changes the reading framework of the translation process. As a result, there is a complete loss of normal protein structure and function.

Question 6.
Explain different types of translocation in chromosomes with a suitable diagram.
Answer:
Translocation is a biological process in which the transfer of a segment of a chromosome to a non-homologous chromosome occurs.
There are three types of translocation namely:

1. Simple translocation
2. Shift translocation
3. Reciprocal translocation

(i) Simple translocation: In this, a single break is made in only one chromosome and the broken segment gets to attach to one end of a non-homologous chromosome. In nature, it is very rare.
(ii) Shift translation: In this* the broken segment of a chromosome is inserted interstitially in a non-homologous chromosome.
(iii) Reciprocal translocation: In this, the mutual exchange of chromosomal segments between two non-homologous chromosomes. It is otherwise known as illegitimate crossing over. It is subdivided into two types namely homozygous translocation and heterozygous translocation.
(a) Homozygous translocation:
Translocation is involved between both the chromosomes of two pairs. In this, two homologous of each translocated chromosomes are identical.
(b) Heterozygous translocation:
In this type of translocation, only one of the chromosomes from each pair of two homologous chromosomes is involved in translation. The remaining chromosome is normal.
Translocation plays a vital role in the formation of new species.

Choose the correct answers.

1. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q) -(iv); (r)-(i); (s)-(ii)
(c) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(b) (p)-(iii); (q) -(iv); (r)-(i); (s)-(ii)

2. Match the following:

(a) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(b) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
Answer:
(a) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

3. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
Answer:
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)

4. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(iii); (q)-(i); (r)-(iv); (s)-(ii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(c) (p)-(iii); (q)-(i); (r)-(iv); (s)-(ii)

5. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(U); (q)-(i); (r)-(iv); (s)-(iii)
(c) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
Answer:
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

6. Loss of a pair of chromosomes from the diploid set is called:
(a) Monosomy
(b) Nullisomy
(c) Double nullisomy
(d) Hypoploidy
Answer:
(b) Nullisomy

7. Chemical mutagenesis was first reported by:
(a) H.J.Muller
(b) T.H.Morgan
(c) C.Auerbaek
(d) M.S.Swaminathan
Answer:
(c) C.Auerbaek

8. Miller was the first to find out physical mutagen in:
(a) Maize
(b) Guineapig
(c) Nicotiana
(d) Drosophila
Answer:
(d) Drosophila

9. Multiple alleles associated with self- sterility was found in:
(a) Maize
(b) Nicotiana
(c) Wheat
(d) Papaya
Answer:
(b) Nicotiana

10. Incomplete linkage was observed is maize by:
(a) Punnet
(b) T.H.Morgan
(c) Hutchinson
(d) C.B.Bridges
Answer:
(c) Hutchinson

11. Choose the odd man out:
(a) T.H.Morgan
(b) C.B.Bridges
(c) H.J.Muller
(d) William Bateson
Answer:
(c) H.J.Muller

12. Find out the odd one:
(a) X-ray
(b) Gamma rays
(c) Cosmic rays
(d) Nitrous oxide
Answer:
(d) Nitrous oxide

13. Identify the odd one out:
(a) Caffeine
(b) Mustard gas
(c) Enthrosine
(d) Etsy urethane
Answer:
(a) Caffeine

14. Choose the odd man out:
(a) M.S.Swaminathan
(b) Alfred H. Sturtevant
(c) Muller
(d) Stadler
Answer:
(b) Alfred H. Sturtevant

15. Identify the odd one out:
(a) Insertion
(b) Deletion
(c) Translocation
(d) Terminalisation
Answer:
(d) Terminalisation

16. Which of the following in the correct pair?

Answer:
(b)

17. Identify the incorrect pair:

Answer:
(c)

18. Which of the following in the correct pair?

Answer:
(c)

19. Find out the incorrect pair:

Answer:
(d)

20. Which of the following is the correct pair?

Answer:
(b)

21. Assertion: Genes are hereditary units and they carry genetic information from one generation to the next generation.
Reason: The genes are arranged in chromosomes in linear order.
(a) Assertion is correct, Reason is the correct explanation of Assertion.
(b) Assertion is correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is the correct explanation of Assertion.
(d) Assertion and Reason are wrong.
Answer:
(b) Assertion is correct, Reason is not the correct explanation of Assertion.

22. Assertion: If two linked genes are sufficiently apart, the changes of their separation are possible.
Reason: If two linked genes are apart, the chances of crossing over is more.
(a) Assertion is correct, Reason is the correct explanation of Assertion.
(b) Assertion is correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is the correct explanation of Assertion.
(d) Assertion and Reason are wrong.
Answer:
(a) Assertion is correct, Reason is the correct explanation of Assertion.

23. Assertion: During synapsis, the homologous chromosomes are aligned side by side, resulting is pairing of homologous chromosomes.
Reason: Synaptonemal complex an organized structure of filaments are responsible for synapsis.
(a) Assertion is correct, Reason is the correct explanation of Assertion.
(b) Assertion is correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is the correct explanation of Assertion.
(d) Assertion and Reason are wrong.
Answer:
(a) Assertion is correct, Reason is the correct explanation of Assertion.

24. Assertion: Crossing over results in the formation of new combination of characters in an organism.
Reason: During crossing over segments of DNA are broken and recombined to produce new combination of alleles.
(a) Assertion is correct, Reason is the correct explanation of Assertion.
(b) Assertion is correct; Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is the correct explanation of Assertion.
(d) Assertion and Reason are wrong.
Answer:
(a) Assertion is correct, Reason is the correct explanation of Assertion.

25. Assertion (A): In papaya, the sex determination is controlled by four alleles of genes.
Reason (R): Sex determination is a complex process determined by genes and the hormones.
(a) Assertion is correct, Reason is the correct explanation of Assertion.
(b) Assertion is correct, Reason is not the correct explanation of Assertion.
(c) Assertion is not correct, Reason is the correct explanation of Assertion.
(d) Assertion and Reason are wrong.
Answer:
(d) Assertion and Reason are wrong.

26. Which of the following statement is true?
(a) Somatic cells of organism are derived from the zygote by meiotic cell division.
(b) These consists of two non-identical sets of chromosomes.
(c) Somatic cells of organism are derived from the zygote by repeated mitotic cell division.
(d) None of the above.
Answer:
(c) Somatic cells of organism are derived from the zygote by repeated mitotic cell division.

27. Choose the incorrect statement:
(a) Alleles of a gene occur in pairs.
(b) Chromosomes do not occur in pairs.
(c) Homologous chromosomes separate during meiosis.
(d) Chromosomes can separate independently during meiosis.
Answer:
(b) Chromosomes do not occur in pairs.

28. Find out the correct statement.
(a) The crossing over does not take place in male Drosophila.
(b) The crossing over does not take place in female Drosophila.
(c) The crossing over frequency is more between linked genes.
(d) None of the above.
Answer:
(a) The crossing over does not take place in male Drosophila.

29. Indicate the incorrect statement.
(a) Multiple alleles of a series always occupy the same locus in the homologous chromosomes.
(b) No crossing over occurs within these alleles of a series.
(c) Multiple alleles of a series always occupy different locus of different chromosomes.
(d) All the above statements are wrong.
Answer:
(c) Multiple alleles of a series always occupy different locus of different chromosomes.

30. Indicate the correct statement.
(a) Spontaneous mutation occurs in the presence of known mutagen.
(b) Induced mutation occurs in the absence of known mutagen.
(c) Spontaneous mutation occurs in the absence of known mutagen.
(d) None of the above.
Answer:
(c) Spontaneous mutation occurs in the absence of known mutagen.

Students get through the TN Board 12th Bio Botany Important Questions Chapter 2 Classical Genetics which is useful for their exam preparation.

TN State Board 12th Bio Botany Important Questions Chapter 2 Classical Genetics

Very short answer questions

Question 1.
Define Heredity.
Answer:
Heredity is defined as a phenomenon in which the transmission of characters from parents to offspring takes place.

Question 2.
Define Variation.
Answer:
Variationisthedifferenceinthecharacteristics of the organisms belonging to the natural population or species.

Question 3.
Name any two scientists, who re-discovered Mendel’s experiments.
Answer:

1. Hugo de Vries
2. Carl Correns

Question 4.
Explain back cross.
Answer:
The back cross is the crossing of F₁ hybrids with any one of the parental genotypes.

Question 5.
Enumerate the explanation for the monohybrid cross.
Answer:

1. The expression of only one character of parental characters in F₁ generation.
2. The expression of both characters in the F₂ generation.

Question 6.
Define genotype.
Answer:
Genotype is defined as the genetic constitution of an individual.

Question 7.
Mention any two characters in Pea plants selected by Mendel.
Answer:

1. Plant height.
2. Flower color.

Question 8.
Explain Codominance.
Answer:
Codominance is a phenomenon in which two alleles are both expressed in the heterozygous individual.

Question 9.
Define Pleiotropy.
Answer:
Pleiotropy is defined as a phenomenon in which a single gene affects multiple characters.

Question 10.
Explain briefly dominant Epistasis.
Answer:
Dominant epistasis is a gene interaction in which two alleles of a gene at one locus interfere and suppress or mask the phenotypic expression of a different pair of alleles of another gene at another locus.

Question 11.
Give two examples of Inter-genic interaction.
Answer:

1. Inhibitor genes
2. Duplicate genes.

Question 12.
Mention any two examples of Incomplete dominance.
Answer:

1. Flower colour in Mirabilis jalapa.
2. Flower colour in snapdragon.

Question 13.
Define Lethal genes.
Answer:
A lethal gene is an allele that has the potential to cause the death of an organism.

Question 14.
Mention any two types of lethal genes.
Answer:

1. Conditional lethal gene
2. Balanced lethal gene.

Question 15.
Define Molecular Genetics.
Answer:
Molecular genetics is defined as a branch of genetics, which deals with the structure and function of a gene at the molecular level.

Short answer questions

Question 1.
Distinguish between population genetics and quantitative genetics.
Answer:

Population Genetics	Quantitative Genetics
Population Genetics deals with heredity in groups of individuals for a traits, determined by a few genes.	Quantitative Genetics deals with heredity of traits in groups of individuals. The traits are governed by many genes simultaneously.

Question 2.
Explain briefly about Discontinuous Variation.
Answer:
In a discontinuous variation, two or more allelic forms of one or two major genes control the characteristic of an individual within a population. These characteristics show a limited form of variations, which are genetically determined by inheritance factors. In this type of variation, the individual shows differences without an intermediate form between the parents and there is no overlapping between the two phenotypes. Environmental factors do not affect phenotypic expression. This variation is otherwise called qualitative inheritance. Eg: Style length in Primula and Plant height of garden pea.

Question 3.
Explain Mendel’s law of heredity.
Answer:
Heredity is the process of transformation of characters from parents to offspring. Two rules on heredity were proposed by Mendel, based on the observations on monohybrid cross. The first rule is the law of dominance and the second one is the law of segregation. These rules play an important role in the history of evolution.

Question 4.
What are the types of dominant relationships?
Answer:

1. Complete dominance
2. Incomplete dominance
3. Codominance
4. Overdominance

Question 5.
Distinguish between Intragenic and intergenic gene interactions.
Answer:

Intragenic	Intergenic
Intragenic gene interactions take place between the alleles of the same gene at same locus. This is otherwise known as intra allelic interactions.	Intergenic gene interactions take place between alleles of different genes at different loci. This is otherwise called as inter allelic interactions.

Question 6.
List out three plants, that exhibit codominance.
Answer:

1. Camillia
2. Gossypium hirsutum
3. Gossypium sturtianum

Question 7.
Mention three examples of non-allelic interactions.
Answer:

1. Fruit colour in summer squash
2. Flower colour in sweet peas
3. Grain colour in maize

Question 8.
Give three examples of polygenic inheritance.
Answer:

1. Skin colour in human being.
2. Wheat kernel colour.
3. Height of human being.

Question 9.
What is polygenic inheritance?
Answer:
Polygenic inheritance is a phenomenon in which a group of genes together determine the phenotypic expression of a single character. The polygenic inheritance was first demonstrated by H. Nilsson-Ehle in 1909 in wheat kernels.

Question 10.
What is meant by extra chromosomal inheritance?
Answer:
Chromosomes are the location of genes, which determine the characters of the individual. But in certain traits, the DNA present in chloroplast and mitochondria decide certain characters. It is a kind of Non-Mendelian inheritance. As this involves cytoplasmic organelles like chloroplast and mitochondria, that act as inheritance vectors, it is called extrachromosomal inheritance through independent, self-replicating plasmalogens.

Long answer questions

Question 1.
Explain the analytical and empirical approach of his experiments.
Answer:
In all Mendel’s experiments, be chose two contrasting characters of a single locus. He assumed that two distinct factors exist for a single trait. The recessive trait does not disappear in the F generation and it is hidden or marked in the F₁ generation and reappear in F₂ generation, in which it contributes to 25% of offspring. Mendel got a 3:1 ratio in F₂ generation when he crossed a homozygous dominant and recessive trait. Hence he concluded that tall and dwarf alleles of F heterozygote segregate randomly into gametes. Mendel is the first biological scientist to use quantitative analysis in biological research.

Mendel’s analytical approach is an outstanding scientific achievement. His breeding experiments are planned meticulously and precisely executed to show that the hereditary materials are transmitted from one generation to another. Though he was not aware of genes during his experiments, he attributed factors, which are responsible for deciding characters. Now the factors are called genes. His approach is empirical and the laws arrived through this approach are known as empirical laws.

Question 2.
Define test cross. Explain it with an example.
Answer:
A test cross is defined as a cross between an individual of unknown genotype with a homozygous recessive.
In F₁ generation of Mendel’s monohybrid cross of tall and dwarf pea plants, he got only tall plants. In F₂ generation the tall and dwarf plants were in the ratio 3:1. He self-pollinated the dwarf F₂ plants and he got only dwarf plants in F₃ and F₄ generation so he concluded that the genotype of the dwarf plant was homozygous recessive (tt). But the genotype of tall plants TT or Tt cannot be predicted. Mendel crossed the tall plants of F₂ with the homozygous recessive dwarf plant. This is known as a test cross. From the progenies of the test cross, the genotype of tall plants can easily be identified. Thus a typical test cross is to cross an organism showing dominant phenotype is crossed with the recessive parent instead of self crossing. Therefore test cross can be used to identify whether an individual is homozygous or heterozygous for the dominant character.

Question 3.
What is the molecular explanation for Mendel’s tall and dwarf planets?
Answer:
A single gene with two alleles controls the height of the pea plant. The difference in height of the plant is due to:

1. The pea plant cells have the ability to convert a precursor molecule of gibberellins into an active form (GA₁).
2. The dominant allele of the gene (Le), which codes for a protein, a functional enzyme, which helps in the gibberellin synthesis pathway and catalyzes the production of gibberellins (GA₁). When the allele is dominant even if it is double (Le Le) or single (Le le) it produces gibberellins resulting in tall plants. The dwarf pea plants, which have two recessive alleles (le le) cannot code for functional protein resulting in dwarf plants.
   

Question 4.
Tabulate examples of Inter-genic interaction with their F₂ ratio.
Answer:

Choose the correct answers:

1. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(c) (p)-(iii); (q)-(ii); (r)-(iv); (s)-(i)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

2. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(b) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(i)
Answer:
(a) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)

3. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(c) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

4. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(c) (p)-(iii); (q)-(i); (r)-(iv); (s)-(ii)
(d) (p)-(ii); (q)-(iv); (r)-(i); (s)-(iii)
Answer:
(d) (p)-(ii); (q)-(iv); (r)-(i); (s)-(iii)

5. Choose the odd man out:
(a) Phenotype
(b) Homozygous
(c) Heterozygous
(d) Allele
Answer:
(a) Phenotype

6. Choose the odd one out:
(a) Complete dominance
(b) Lethal genes
(c) Multiple alleles
(d) Epistatic
Answer:
(d) Epistatic

7. Identify the odd man out:
(a) Hugo de Vries
(b) Linnaeus
(c) Carl Correns
(d) Erich Von Tschermak
Answer:
(b) Linnaeus

8. Choose the odd one out:
(a) Codominance
(b) Complementary
(c) Supplementary
(d) Inhibitory
Answer:
(a) Codominance

9. Choose the correct pair.

Answer:
(d)

10. Find out the incorrect pair.

Answer:
(c)

11. Choose the correct pair.

Answer:
(b)

12. Find out the incorrect pair.

Answer:
(c)

13. Male sterility in pearl maize is due to:
(a) Independent inheritance
(b) Mitochondrial inheritance
(c) Chloroplast gene inheritance
(d) Codominance
Answer:
(b) Mitochondrial inheritance

14. The polygenic inheritance was first demonstrated by:
(a) E. Baur
(b) Carl Correns
(c) Hugo de Vries
(d) H. Nilsson – Ehle
Answer:
(d) H. Nilsson – Ehle

15. In dominant epistasis in summer squash, the F2 generation the phenotypic ratio is:
(a) 9:3:3:1
(b) 12:3:1
(c) 9:7
(d) 15:1
Answer:
(b) 12:3:1

16. In Polygenic inheritance the production of medium dark red color is due to:
(a) Four R genes
(b) Two R genes
(c) Three R genes
(d) Absence of R – gene
Answer:
(c) Three R genes

17. Intra-genic interaction includes:
(a) Dominant epistasis
(b) Duplicate genes
(c) Inhibitor genes
(d) Codominant genes
Answer:
(d) Codominant genes

18. Assertion: Two alleles of a gene at one locus suppress or mask the phenotypic expression of a different pair of alleles of another gene at another locus in dominant epistasis.
Reason: Inter locus interactions take place between the alleles at different loci i.e., between alleles of different genes.
(a) Assertion is true; Reason is wrong.
(b) Assertion is wrong; Reason is true.
(c) Both Assertion and Reason are true.
(d) Both Assertion and Reason are wrong.
Answer:
(c) Both Assertion and Reason are true.

19. Assertion: The phenomenon in which two alleles are both expressed in the heterozygous condition is known as codominance.
Reason: Thecodominancewasdemonstrated in plants with the help of electrophoresis.
(a) The Assertion is true; the Reason is false.
(b) The Assertion is false; the Reason is true.
(c) Both Assertion and Reason are true.
(d) Both Assertion and Reason are false.
Answer:
(a) The Assertion is true; the Reason is false.

20. Assertion: In a monohybrid cross, when two homozygous dominant and recessive traits are crossed, an intermediate character is found in F₁ generation:
Reason: This may be due to the codominance of two alleles.
(a) Assertion is right; the Reason is wrong.
(b) Assertion is false; the Reason is true.
(c) Both Assertion and Reason are true.
(d) Both Assertion and Reason are false.
Answer:
(d) Both Assertion and Reason are false.

21. Which of the following statement is correct?
(a) The dihybrid cross involves individuals differencing in one character.
(b) The recessive back cross helps to identify the homozygosity of the hybrid.
(c) The dihybrid cross is a genetic cross in which- individuals differing in two characters are involved.
(d) None of the above statements is correct.
Answer:
(c) The dihybrid cross is a genetic cross in which- individuals differing in two characters are involved.

22. ChoOse the incorrect statement.
(a) Two identical alleles of a gene are called heterozygous.
(b) Two different alleles of a gene are called heterozygous.
(c) Two identical alleles of a gene are called homozygous
(d) An individual with two dominant alleles is called homozygous dominant.
Answer:
(a) Two identical alleles of a gene are called heterozygous.

23. Find out the correct statement.
(a) Mendelian experiments prove that a single gene controls more than one character.
(b) Independent assortment leads to genetic diversity.
(c) Back cross involves the cross between the F₂ offspring with F₁ parents.
(d) Independent assortment leads to genetic homozygosity.
Answer:
(b) Independent assortment leads to genetic diversity.

24. Which of the following statement is false?
(a) Intragenic gene interaction takes place between the alleles of the same gene.
(b) Intragenic gene interaction takes place between the alleles at the same locus.
(c) Intergenic gene interaction takes place between alleles of different locus.
(d) All the above statements are wrong.
Answer:
(d) All the above statements are wrong.

25. Choose the correct statement.
(a) Codominance type of inheritance is found in snapdragon.
(b) The inheritance of sickle cell anemia is a typical example of pleiotropy.
(c) Polygenic inheritance is seen in the flower color of pea plants.
(d) The expression of inhibitor gene leads to male sterility in plants.
Answer:
(b) The inheritance of sickle cell anemia is a typical example of pleiotropy.

Students get through the TN Board 12th Bio Botany Important Questions Chapter 1 Asexual and Sexual Reproduction in Plants which is useful for their exam preparation.

TN State Board 12th Bio Botany Important Questions Chapter 1 Asexual and Sexual Reproduction in Plants

Very short answer questions

Question 1.
Define asexual reproduction.
Answer:
Asexual reproduction is defined as the phenomenon in which the propagation of own species takes place without the involvement of gametes.

Question 2.
Mention any two methods of asexual reproduction for example.
Answer:

1. Yeast – Budding.
2. Bacteria – Binary fission.

Question 3.
What is meant by epiphyllous buds?
Answer:
In plants like Brydphyllum, the leaf is notched on its margin. The buds that develop on these notches are called epiphyllous buds.

Question 4.
List out two types of layering.
Answer:

1. Mount layering.
2. Air layering.

Question 5.
Define totipotency.
Answer:
Totipotency is defined as a phenomenon in which the genetic ability of a plant cell to produce an entire plant under suitable conditions.

Question 6.
Mention any two disadvantages of the conventional method of plant propagation.
Answer:

1. Viral infected new plants are produced when the infected plants are used as parents.
2. For vegetative propagation, bulky vegetative structures are needed and the storage and handling of these materials become difficult.

Question 7.
Define microsporogenesis.
Answer:
Microsporogenesis is a process in which the formation of haploid microspores is framed from diploid microspore mother cell through meiosis.

Question 8.
What is corpusculum?
Answer:
The corpusculum is a clamp or clip like sticky structure in which the pollinia are attached.

Question 9.
Mention any two allergic reactions due to pollen grains:
Answer:

1. Asthma
2. Bay fever

Question 10.
What is meant by chalaza?
Answer:
Chalaza is the merging part of the nucellus, the integument, and the funicle at the basal region of the ovule.

Question 11.
What is autogamy?
Answer:
The transfer of pollen on the stigma of the same flower is called autogamy. Autogamy is otherwise called self-pollination.

Question 12.
What is meant by herkogamy?
Answer:
Herkogamy is an adaptation in which die essential organs like stamens and stigmas are arranged in such a way that self-pollination becomes impossible. Eg: Hibiscus.

Question 13.
Mention any two birds, that help in pollination.
Answer:

1. Humming birds,
2. Sun birds.

Question 14.
Define fertilization.
Answer:
Fertilization is defined as the process in which the fusion of male and female gamete takes place.

Question 15.
Define porogamy.
Answer:
Porogamy is the process in which the pollen tube enters the ovule through the micropyle.

Short answer questions

Question 1.
List out any three scientists who worked on plant embryology.
Answer:

1. S.C. Maheswari
2. K.V. Krishnamurthy
3. S. Guha.

Question 2.
Mention and three advantages of vegetative reproduction.
Answer:

1. For the propagation of a species, only one individual plant is enough.
2. The progenies are genetically identical.
3. In some plants like Spinifex, vegetative reproduction enables them to spread rapidly.

Question 3.
Explain briefly about approach grafting.
Answer:
In approach grafting, the rooting occurs both in scion and stock, which is grown in a pot. The pot is brought near the scion. A small slice is cut from the stem, which is of the same thickness. The cut surfaces of both stock and scion are brought together and tied with tape in order to hold together. After 1-4 weeks, the plant is detached by cutting the tip of stock and base of the scion and grown in a separate pot.

Question 4.
Explain the term micropropagation.
Answer:
Micropropagation is a method of plant propagation in which the regeneration of a whole plant occurs from a single cell, tissue, or small piece of vegetative structures through tissue culture.

Question 5.
Mention any three functions of the tapetum.
Answer:

1. Tapetum supplies nutrition to the developing microspores.
2. It plays an important role in pollen wall formation.
3. The exine proteins, responsible for rejection reaction are derived from tapetal cells.

Question 6.
Explain pollenkitt with its function.
Answer:
Pollenkitt is a yellow or orange coloured layer contributed by the tapetum. They are made up of carotenoids or flavonoids. It forms an oily, thick viscous coating over pollen surface to attract insects and to protect from damage due to UV radiation.

Question 7.
What are the types of cross-pollination? and Explain.
Answer:
The transfer of pollen on the stigma of another flower is referred as cross-pollination.
Cross-pollination is of two types.

1. Geitonogamy: In this process, the pollen deposits on the stigma of another flower of the same plant. It usually occurs in monoecious plants. Though it is functionally cross-pollination, it is similar to autogamy because the pollen comes from the same plant.
2. Xenogamy: When the transfer of pollen on another flower of a genetically different plant of the same species, it is called xenogamy.

Question 8.
Distinguish monoecious and dioecious plants.
Answer:

Monoecious	Dioecious
Male and female flowers occur on the same plant. Eg: coconut.	Male and female flowers occur on Afferent plants. Eg: Papaya, date palm.
In some plants caster and maize autogamy is prevented. But geitonogamy occurs.	In this both autogamy and geitonogamy are prevented.

Question 9.
Explain entomophily.
Answer:
Entomophily refers to pollination by insects, which include bees, moths, butterflies wasp, and beetles. Among them, the dominant pollinators are the bees. They are the main flower visitors. The majority of angiosperm are pollinated by insects. Entomophily is the most common type of pollination.

Long answer questions

Question 1.
Describe the methods of layering.
Answer:
Layering is an artificial method of vegetative propagation, in which the stem of a parent plant is made to develop roots. When the stem develops roots, the rooted portion is cut and planted to grow as a new plant. Eg: Ixora and Jasminum. There are two types of layering.

1. Mound layering: when plants have flexible branches, the lower branch with leaves is bent to the ground and buried in the soil. So that the tip of the branch
   is exposed above the soil. The part of the stem which is buried in the soil develops roots and a cut is made in the parent plant so that the buried part grows into a new plant.
2. Air layering: In this method, the stem is girdled at the nodal region and root promoting hormones are applied to the girdled portion, which is covered with damp or moist soil using a polythene sheet. After 2-4 months, roots emerge in these branches. These rooted branches. are removed from the parent plant and grown in a separate pot or ground.

Question 2.
Explain tapetum and its types.
Answer:
Tapetum is the innermost layer of another wall and is derived from the peripheral wall layer and the connective tissue of another lining the anther locule. Thus, the tapetum is dual in origin and gives nourishment to the developing sporogenous tissue, microspore mother cells, and microspores. The cells of the tapetum may be uninucleate or may have more than one nucleus or polyploid nucleus. It also helps in the formation of wall material, sporopollenin, pollenkitt, tryphine and number of proteins that control incompatibility reaction. The fertility and sterility of the microspores or pollen grains are also controlled by tapetum.
Based on the behavior of tapetum, there are two types:

1. Secretary tapetum: In this case, original position, and cellular integrity are retained and supplies nourishment to the developing microspore.
2. Invasive tapetum: It is otherwise known as periplasmodial type of tapetum. In this type, the cells loose their inner tangential and radial walls and the protoplast of all tapetal cells coalesces to form periplasmodium.

Question 3.
Draw the different stages of the development of ovule and embryo sac of polygonum type.
Answer:

Question 4.
Enumerate the characteristic features of anemophilous plants.
Answer:

1. Pendulous, catkin-like flower or spike inflorescence are present.
2. The flowers are brought well above the leaves with an elongated axis of the inflorescence.
3. The perianth is absent or highly reduced.
4. The stamens are numerous with long filaments, exerted and versatile anther.
5. Enormous quantities of pollen grains are produced compared to the number of ovules available for pollination.
6. The pollen grains are minute, light, and dry in order to transport long-distance by the wind.
7. In some plants like Urtica, the anthers burst violently and release the pollen into the air.
8. Stigmas are comparatively large protruding, sometimes branched feathery, and adapted to catch the pollen grains.
9. Generally, a single ovule is present.
10. Flowers are produced before the new leaves appear so that the pollen can be carried by wind without any hindrance of leaves.

Question 5.
Explain the term Apomixis. Add a note on its types.
Answer:
Apomixis is the phenomenon in which reproduction does not involve the union of male and female gamete. Whereas the fertilization involving the union of male and female gametes in flowering plants is called amphimixis. Winkler in 1908 introduced the term apomixis. This is the substitution of usual sexual reproduction and this does not involve meiosis and syngamy.
Apomixis was classified into two types as Recurrent and Non-recurrent by Maheswari in 1950.
Recurrent apomixis: This induces vegetative reproduction and agamospermy. Vegetative reproduction is the propagation of plants by any part other than seeds.
Eg: Bulbs – Allium
Bulbils – Fritilaria imparialis
Runner – Mentha arvensis
Sucker – Chrysanthemum
Agamospermy refers to the processes by which embryos are formed by eliminating meiosis and syngamy.
Non-recurrent apomixis: Haploid embryo sac developed after meiosis, develops into an embryo without fertilization.

Choose the correct answers:

1. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(i); (r)-(iv); (s)-(ii)
Answer:
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)

2. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(iv); (r)-(i); (s)-(ii)
(c) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(c) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

3. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(b) (p)-(iii); (q)-(i); (r)-(iv); (s)-(ii)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)
Answer:
(d) (p)-(iii); (q)-(iv); (r)-(ii); (s)-(i)

4. Match the following:


(a) (p)-(iii); (q)-(i); (r)-(iv); (s)-(ii)
(b) (p)-(iv); (q)-(ii); (r)-(iii); (s)-(i)
(c) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
(d) (p)-(ii); (q)-(iii); (r)-(iv); (s)-(i)
Answer:
(a) (p)-(iii); (q)-(i); (r)-(iv); (s)-(ii)

5. Match the following:

(a) (p)-(iv); (q)-(iii); (r)-(i); (s)-(ii)
(b) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)
(c) (p)-(iv); (q)-(i); (r)-(ii); (s)-(iii)
(d) (p)-(ii); (q)-(i); (r)-(iv); (s)-(iii)
Answer:
(b) (p)-(iv); (q)-(iii); (r)-(ii); (s)-(i)

6. Who discovered the process of syngamy?
(a) E. Strasburger
(b) G.B. Amici
(c) Hofmeister
(d) E. Hanning
Answer:
(a) E. Strasburger

7. Vegetative propagation takes place through leaf buds in:
(a) Hibiscus
(b) Begonia
(c) Mango
(d) Malus
Answer:
(b) Begonia

8. The inner tangential wall of anther develops bands of:
(a) Polysaccharides
(b) Glycoprotein
(c) a cellulose
(d) p cellulose
Answer:
(c) a cellulose

9. Matured anther cavity is filled with:
(a) Megaspore
(b) Young microspore
(c) Embryo sac
(d) Pollen grain
Answer:
(d) Pollen grain

10. Epihydrophily type of pollination takes place in:
(a) Hydrilla
(b) Elodea
(c) Ipomea
(d) Pistia
Answer:
(b) Elodea

11. Choose the odd one out.
(a) Protogyny
(b) Cleistogamy
(c) Autogamy
(d) Homogamy
Answer:
(a) Protogyny

12. Find out the odd one:
(a) Cutting
(b) Grafting
(c) Micropropagation
(d) Air layering
Answer:
(c) Micropropagation

13. Choose the odd one.
(a) Endothecium
(b) Nucellus
(c) Tapetum
(d) Epidermis
Answer:
(b) Nucellus

14. Identify the odd one.
(a) Chalaza
(b) Endothelium
(c) Hilum
(d) Ubisch bodies
Answer:
(d) Ubisch bodies

15. Choose the odd one out.
(a) Orthotropous
(b) Microsporous
(c) Hemianatropous
(d) Campylotropous
Answer:
(b) Microsporous

16. Choose the incorrect pair.

Answer:
(d)

17. Choose the correct pair.

Answer:
(c)

18. Choose the incorrect pair.

Answer:
(d)

19. Identify the correct pair.

Answer:
(c)

20. Choose the incorrect pair.


Answer:
(d)

21. Assertion: The cells of endothecium are hygroscopic in nature.
Reason: They absorb water from air.
(a) Assertion is true and the Reason is false.
(b) Assertion is false and the Reason is true.
(c) Both Assertion and Reason are true.
(d) Both Assertion and Reason are false.
Answer:
(c) Both Assertion and Reason are true.

22. Assertion: P0llen grains are the immediate product of meiosis of the microspore mother cell.
Reason: the p0llen grains have a diploid number of chromosomes.
(a) Assertion is true and the Reason is false.
(b) Assertion is false and Reason is true.
(c) Both Assertion and Reason are true.
(d) Both Assertion and Reason are false.
Answer:
(d) Both Assertion and Reason are false.

23. Assertion: The filiform apparatus of synergids guides the pollen tube into the egg.
Reason: It helps in the absorption and conduction of nutrients.
(a) Assertion is true and the Reason is false.
(b) Assertion is false and the Reason is true.
(c) Both Assertion and Reason are true.
(d) Both Assertion and Reason are false.
Answer:
(a) Assertion is true and the Reason is false.

24. Assertion: self-p0llinati0n is possible only in those plants which bear bisexual flowers.
Reason: The availability of pollen and stigma are in the same flower for self-pollination.
(a) Assertion is true and the Reason is false.
(b) Assertion is false and the Reason is true.
(c) Both Assertion and Reason are true.
(d) Both Assertion and Reason are false.
Answer:
(c) Both Assertion and Reason are true.

25. Assertion: In some bisexual flowers, anthers and stigma mature at different times.
Reason:
This is a special adaptation in plants to prevent cross-fertilization.
(a) Assertion is true and the Reason is false.
(b) Assertion is false and the Reason is true.
(c) Both Assertion and Reason are true.
(d) Both Assertion and Reason are false.
Answer:
(d) Both Assertion and Reason are false.

26. Which of the following statement is correct?
(a) Budding is the method of asexual reproduction in spirogyra.
(b) Formation of conidia is the method of asexual reproduction in penicillium.
(c) asexual reproduction in planaria is the production of gametes.
(d) In hydra, the asexual reproduction is through the fragmentation method.
Answer:
(b) Formation of conidia is the method of asexual reproduction in penicillium.

27. Choose the incorrect statement.
(a) In mango, grafting is followed for vegetative propagation.
(b) In moringa, the stem cutting method is followed for vegetative propagation.
(c) In Hibiscus, leaf-cutting method is followed for vegetative propagation.
(d) In the Ixora plant, the layering method is followed by vegetative propagation.
Answer:
(c) In Hibiscus, leaf-cutting method is followed for vegetative propagation.

28. Find out the correct statement.
(a) Androecium and gynoecium are died essential organs for reproduction in plants.
(b) In protandrous flowers die gynoecium matures first.
(c) In protogynous flowers the androecium matures first.
(d) None of the above statements is correct.
Answer:
(a) Androecium and gynoecium are died essential organs for reproduction in plants.

29. Which of the following statement is false?
(a) The formation of haploid microspores from diploid microspore mother cell is through meiosis.
(b) The primary sporogenous cells may undergo a few meiotic divisions to form sporogenous tissue.
(c) The microspore mother cells are formed from the sporogenous tissue.
(d) All the above statements are correct.
Answer:
(b) The primary sporogenous cells may undergo a few meiotic divisions to form sporogenous tissue.

30. Choose the correct statement.
(a) Orthotropous type of ovule is present in Cactaceae.
(b) Anatropous type of ovules are found in dicots and monocots.
(c) Hemianatropous type of Ovule is present in Alismataceae.
(d) Amphitropous type of ovule is present in Cactaceae.
Answer:
(b) Anatropous type of ovules are found in dicots and monocots.