Bhagya

Students can download 10th Social Science Geography Chapter 6 Physical Geography of Tamil Nadu Questions and Answers, Notes, Samacheer Kalvi 10th Social Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Social Science Solutions Geography Chapter 6 Physical Geography of Tamil Nadu

Samacheer Kalvi 10th Social Science Physical Geography of Tamil Nadu Text Book Back Questions and Answers

I. Choose the correct answer

Question 1.
The latitudinal extent of Tamil Nadu is:
(a) 8°4’N to 13°35’N
(b) 8°5’S to 13°35’S
(c) 8°0’N to 13°5’N
(d) 8°0’S to 13°05’S
Answer:
(a) 8°4’N to 13°35’N

Question 2.
The longitudinal extent of Tamil Nadu is …………………
(a) 76°18′ E to 80°20’E
(b) 76° 18′ W to 80°20′ W
(c) 86°18’Eto 10°20’E
(d) 86°18′ W to 10°20′ W
Answer:
(a) 76°18′ E to 80°20’E

Question 3.
The highest peak in Tamil Nadu is:
(a) Anaimudi
(b) Doddabetta
(c) Mahendragiri
(d) Servarayan
Answer:
(b) Doddabetta

Question 4.
Which of the following passes is not located in the Western Ghats of Tamil Nadu?
(a) Palghat
(b) Shencottah
(c) Bhorghat
(d) Achankoil
Answer:
(c) Bhorghat

Question 5.
Which one of the following rivers is flow into the Arabian Sea?
(a) Periyar
(b) Cauvery
(c) Chittar
(d) Bhavani
Answer:
(a) Periyar

Question 6.
The district with largest mangrove forest cover in Tamil Nadu is ……………
(a) Ramanathapuram
(b) Nagapattinam
(c) Cuddalore
(d) Theni
Answer:
(c) Cuddalore

Question 7.
The forest cover of Tamil Nadu as per 2017 Indian Forest Report is:
(a) 20.21%
(b) 20.31%
(c) 21.20%
(d) 21.30%
Answer:
(a) 20.21%

Question 8.
Retreating monsoon wind picks up moisture from …………….
(a) Arabian sea
(b) Bay of Bengal
(c) Indian Ocean
(d) Timor sea
Answer:
(b) Bay of Bengal

Question 9.
hich of the following district is affected by sand dunes to a large extent?
(a) Theni
(b) Madurai
(c) Thanjavur
(d) Ramanathapuram
Answer:
(d) Ramanathapuram

Question 10.
The district which has the largest forest cover in Tamil Nadu is ………………
(a) Dharmapuri
(b) Vellore
(c) Dindigul
(d) Erode
Answer:
(a) Dharmapuri

II. Fill in the blanks

1. The plateau which lies between the Nilgiris and Dharmapuri districts is ………………
2. ……………… is the highest peak in the southern most part of the Eastern Ghats.
3. The riverine Island of Srirangam is located between ……………… and ……………… branches of cauvery.
4. ……………… soil is suitable for the cultivation of tea and coffee plants.
5. ……………… is the Tamil Nadu state animal which is found in ………………

Answers:

1. Coimbatore
2. Solaikaradu
3. Northern (Coleroon or Kollidam), and Southern (Cauvery)
4. Laterite
5. Nilgiri Tahir, Western Ghats, Tamil Nadu and Kerala

III. Match the following

Answer:
A. (iv)
B. (iii)
C. (ii)
D. (v)
E. (i)

IV. Assertion type Question

Question 1.
Assertion (A): Tamil Nadu does not receive much rainfall from southwest monsoon.
Reason (R): It is situated in the rain shadow area of the Western Ghats.
(a) Both (A) and (R) are true and (R) explains (A).
(b) Both (A) and (R) are true but, (R) does not explain (A).
(c) (A) is true but, (R) is false.
(d) (R) is true but, (A) is false.
Answer:
(a) Both (A) and (R) are true and (R) explains (A).

Question 2.
Assertion (A): Red soil is rich in iron oxides.
Reason (R): It is formed by leaching.
(a) Both (A) and (R) are true and (R) explains (A).
(b) Both (A) and (R) are true but, (R) does not explain (A).
(c) (A) is true but, (R) is false.
(d) (R) is true but, (A) is false.
Answer:
(c) (A) is true but, (R) is false.

V. Answer the following in brief

Question 1.
State the boundaries of Tamil Nadu.
Answer:
Tamil Nadu is surrounded by the Bay of Bengal in the east, Indian ocean in the South, Kerala and Karnataka in the west and Andhra Pradesh on the North.

Question 2.
List out the districts of Tamil Nadu which are partly/fully located on Eastern and Western Ghats separately.
Answer:

• Districts of Tamil Nadu Partly / fully located on Eastern Ghats and Western Ghats.
• Districts on Eastern Ghats: Vellore, Thiruvannamalai, Salem, Nammakal, Trichirapalli, Perambalur.
• Districts on Western Ghats: Nilgiris, Kanyakumari, Dindigul, Virudhunagar.

Question 3.
What is ‘Teri??
Answer:
The sand dunes formed along the coast of Ramanathapuram and Thoothukudi districts are called Teri.

Question 4.
How is coastal plain formed?
Answer:
Coastal plains is formed by die rivers that flow towards east and drain in the Bay of Bengal in Tamil Nadu. It is more than 80 kilometers wide at some places.

Question 5.
Name the major islands of Tamil Nadu.
Answer:
Pamban, Hare, Krusadai, Nallathanni Theevu, Pullivasal, Srirangam, Upputanni, Island Grounds, Kattupalli Island, Quibble Island and Vivekananda Rock Memorial are some major islands of Tamil Nadu.

Question 6.
Name the tributaries of river Thamirabarani.
Answer:
Karaiyar, Servalar, Manimuthar, Gadananathi, Pachaiyar, Chittar, and Ramanathi are the main Tributaries of Thamirabarani.

Question 7.
Define Disaster Risk Reduction.
Answer:
The concept and practice of disaster risks through systematic efforts to analyse and manage the causal factors of disasters including through reduced exposure to hazards, lessened vulnerability of people and property, wise management of land and environment and improved preparedness for adverse events.

Question 8.
During cyclone, how does the Meterological department warn the . fishermen?
Answer:
During Cyclone the Meterological Department warn the fishermen through State Government officials and broadcast of warnings through All India Radio and National Regional (Doordharshan) telecast programme. During Cyclone four stages of warning are given by the Meteorological Department to keep the fishermen alert and to return back who ventured into the sea through coast guards also.

VI. Distinguish between the following

Question 1.
Western Ghats and Eastern Ghats.
Answer:
Western Ghats (in Tamil Nadu):

1. Western Ghats extends from the Nilgiris in the North to Marunthuvazh malai at Swamithope in Kanyakumari in the South.
2. It is a continuous range.
3. Doddabetta (in the Nilgiris) is the highest peak.
4. It’s height ranges from 2000mts to 3000 mts above sea level.
5. Important hills are Nilgiris, Anaimalai and palani hills etc.

Eastern Ghats (in Tamil Nadu):

1. Major hills of the Eastern Ghats of Tamil Nadu are located in the Northern districts of the State.
2. It is discontinuous dissected at many places by the east flowing rivers.
3. Solaikaradu in the Servarayan hills is the highest peak.
4. It’s height ranges from 1,100 mts to 1600 mts above sea level.
5. Javadhu, Kalvarayan and Servarayan etc are some of the major hills.

Question 2.
Southwest monsoon and Northeast monsoon.
Answer:
Southwest Monsoon:

1. Period of Southwest monsoon is from March to May.
2. Tamil Nadu is located in the rainshadow region for the wind hence gets only less rainfall.
3. Rainfall decreases from West to East,
4. CoimbatorePlateau,Kanyakumari and Tirunelveli districts receives 50 – 100 cm rainfall during this period.

Northeast Monsoon:

1. Period of Northeast Monsoon is from October and lasts till mid – December.
2. 48% of annual rainfall to Tamil Nadu is from this wind.
3. It is the rainy season for the districts of Tamil Nadu.
4. Coastal districts get nearly 60% of annual rainfall and interior districts get 40 – 50 cm rainfall.

Question 3.
Tropical evergreen and Tropical deciduous forests.
Answer:
Tropical Evergreen Forests:

1. This types of forest is found in the areas of heavy rainfall.
2. It is dense, multilayered forest.
3. The major type of trees found in the forests are Cinnamon, Malabar ironwood kindal, jamun etc.
4. It is found in the upper slopes of Western Ghats of Tirunelveli, Kanyakumari, Nilgiris and Coimbatore districts.

Tropical Deciduous Forests:

1. It is found in the regions of sub tropical climate with moderate rainfall.
2. The trees in this forest shed their leaves during dry season.
3. The major trees are kapok, kadamba, axle wood, bamboo, dog- teak, silk cotton etc some trees are economically important.
4. It is found in the margin of semi evergreen and evergreen forests – Servarayan, Kollimalai, Pachaimalai Eastern Ghats.

VII. Give reasons for the following

Question 1.
Eastern Ghats are not a continuous range.
Answer:
Eastern Ghats is a discontinuous and irregular one. It is dissected at many places by the rivers, which drain into the Bay of Bengal. Its height ranges from 1,100 to 1,600 metres.

Question 2.
Tamil Nadu receives low rainfall during Southwest monsoon.
Answer:
Tamil Nadu is located in the rainshadow region for the wind which blows from the Arabian sea. As a result Tamil Nadu receives low rainfall during Southwest monsoon.

Question 3.
Alluvial soil is fertile.
Answer:
Alluvial soil are formed by the deposition of silt by the rivers. Alluvial soils are generally fertile as they are rich in minerals such as lime, potassium, magnesium, nitrogen and phosphoric acid. It is deficient in nitrogen and humus. It is porous and loamy.

Question 4.
Cuddalore is a multiprone disaster zone.
Answer:
Cuddalore is a multiprone disaster zone, because it is located under the very high cyclone prone zone and flood prone zone. More over it is an coastal area often affected by the vulnerable natural disasters.

VIII. Answer the following in a paragraph

Question 1.
Describe the nature of the plateau region of Tamil Nadu.
Answer:

• Plateau of Tamil Nadu is located between the Western Ghats and the Eastern Ghats.
• It is roughly triangular in shape and covers an area of about 60,000 sq. km.
• Its height increases from east to west. Its height ranges between 150 and 600 m.
• This plateau is broader in the north and very narrow in the south and it has many subdivisions.
• Bharamahal plateau is a part of the Mysore plateau situated in the northwestern part of Tamil Nadu. Dharmapuri and Krishnagiri districts are located in this region.
• Coimbatore plateau lies between the Nilgiris and Dharmapuri districts. Its height varies from 150 to 450 metres. Moyar river separates this plateau from the Mysore plateau.
• Rivers like Bhavani, Noyyal and Amaravathi, which originate from Western Ghats form Valleys in the region. Many intermontane plateaus are found in the region of the Nilgiris. Sigur plateau is one such plateau.
• Madurai plateau found in Madurai district extends up to the foothills of the Western Ghats. Vaigai and Thamirabarani basins are located in the zone.

Question 2.
Write an account on river Kaveri.
Answer:
Origin of River Kaveri: The river Kaverioriginates in the Brahmagiri hills of Kodagu (coorg) district of Karnataka in the Western Ghats. It serves as the boundary between Karnataka and Tamil Nadu for a distance of 64 k.m.

Length of its course in Tamil Nadu: 416 km

Upper course: It enters into Tamil Nadu in the form of Hogenakkal falls in Dharmapuri district. Mettur Dam (Stanely Reservoir) is built across the river in Salem District. A tributary called Bhavani joins Cauvery on the right bank about 45 km from the Mettur Reservoir.

Middle course: Then it takes easterly direction to enter into the plains of Tamil Nadu.

1. At Thirumukkudal 10 km from Karur, two more tributaries Noyyal and Amaravathi confluence the river on the right bank. In this region the river is wider and called ‘Agandra Cauvery’.
2. In Tiruchirappalli the river branches into two. The Northern branch is called Coleroon or Kollidam and the Southern branch remains Cauvery. After flowing for about 16 km, the two branches join again to form the ‘Srirangam Island’.
3. The Grand Anaicut, called as Kallanai was built across the river Cauvery. The deltaic stage begins in the middle course.

Lower course: After Kallanai the river breaks into a large number of distributaries and forms a network all over the delta. River Cauvery merges into Bay of Bengal to the South of Cuddalore.

Question 3.
Explain the characteristic features of summer and winter seasons of Tamil Nadu. Summer Seasons:
Answer:
The apparent migration of the sun towards north during March, April and May result in the reception of vertical sun’s rays by South India. Thus there is a steady rise in temperature from the equator. Hence, Tamil Nadu located to the south of Tropic of Cancer experiences high temperature. Generally, the temperature varies from 30°C to more than 40°C. During this season particularly in the month of May, the southern part of the state receives some rainfall from pre-monsoon showers (Mango/Blossom showers) and some parts experience convectional rainfall.

Winter Seasons:
During January’ and February, the vertical rays of the sun fall between the Tropic of Capricorn and the Equator. Hence, Tamil Nadu and India on the whole receive slanting rays from the sun. So, the weather is slightly cooler during these months. The difference between summer and winter temperature is not very high. Winter temperature in Tamil Nadu varies from 15°C to 25°C. However, in the hill stations, the winter temperature drops below 5°C occasionally. Some valleys in the Nilgiris record even 0°C. This drop in temperature leads to the formation of thick mist and frost. This season is practically dry.

Question 4.
What is desertification and write about the areas affected by it in Tamil Nadu.
Answer:

1. The process by which fertile land becomes desert due to inappropriate agriculture, deforestation, and drought is termed as desertification. It is a type of land degradation which lead to the extension of desert area.
2. In Tamil Nadu Theni, the Nilgiris and Kanyakumari are the worst affected districts by desertification.
3. About 12,000 hectares (120sq. km) were affected by sand deposition in Theni and Rajapalayam.

Question 5.
Bring out the types and distribution of soils in Tamil Nadu.
Answer:
According to their characteristics, soils of Tamil Nadu are classified into five types.

Soil Types	Distribution
Alluvial soil	River valley regions and coastal plains – Thanjavur, Nagapattinam, Cuddalore, Villupuram, Tirunelveli and Kanyakumari.
Black soil	Semi arid regions – Coimbatore, Madurai, Virudhunagar, Tirunelveli and Thoothukudi.
Red soil	Cover two-third areas of Tamil Nadu – particularly in the central district and mainly in Sivagangai and Ramanathapuram.
Laterite soil	Intense leaching areas – parts of Kanchipuram, Thiruvallur and Thanjavur, patches over the mountainous region in the Nilgiris.
Saline soil	Confined to the Coromandel coast – Vedaranyam.

Question 6.
Name the areas which are affected by landslides. What will you do before, during and after landslides?
Answer:
Nilgiris in Tamil Nadu is identified as one of the most vulnerable districts in the country and landslides pose a major threat in this area. The other regions which are prone to land slides are Coimbatore and palani hill of Dindigul district where Kodaikanal hill station is located.

Before: Create awareness; stay alert and awake; monitor the news updates; make evacuation plan; listen for any unusual sounds that might indicate moving debris such as trees cracking, boulders knocking and consider leaving the place of landslide if it is safe to do so.

After: Stay away from the slide area; listen to local radio or television stations for the latest emergency information; watch for flooding, which may occur after a landslide or debris flow; check for injured and trapped persons near the slide, without entering the direct slide area.

IX. Map study

Question 1.
Mark important rivers, distribution of soil and forest types on different Tamil Nadu maps.

(a) Important rivers:

1. Cauvery
2. Palar
3. Then Pennaiyar / Ponnaiyar
4. Vaigai
5. Thamirabarani.

Other rivers:

1. Coleroon or Kollidam
2. Amaravathi
3. Bhavani
4. Noyyal
5. Cheyyar.

(b) Distribution of soil

Soil	Areas
Alluvial	Thiruvarur, Nagapattinam, Villupuram, Cuddalore, Tirunelveli, Kanyakumari and Cauvery Delta.
Black soil	Coimbatore, Madurai, Virudhunagar, Tirunelveli.
Red soil	Sivagangai, Ramanathapuram.
Laterite soil	Kancheepuram, Tiruvallur, Nilgiris.
Saline soil	Coromandel coast, Vedaranyam coast.

img 3

(c) Forest type (Natural vegetation)

1. Tropical evergreen forest: Slopes of Western Ghats Nilgiris, Coimbatore, Tirunelveli, Kanyakumari.
2. Temperature forest: Anaimalai, Palani hills.
3. Tropical deciduous forest: Eastern Ghats, Servarayan, Kollimalai, Pachaimalai.
4. Mangrove forest: Cuddalore, Chidambaram,

TB. PNo: 85
Find Out

Question 1.
Name the first state of India created on linguistic basis.
Answer:

1. Andhra Pradesh was the first State of India created on linguistic basis.
2. Bifurcated from Madras Presidency the Telugu speaking area – Andhra Pradesh on October – 1^st, 1953.

Question 2.
Why was the capital of Tamil Nadu renamed?
Answer:
After India got independence in 1947, the city became the capital of Madras state, which was renamed as Tamil Nadu on 1969. On 17 July 1996 the city known as Madras was officially renamed as Chennai.

Question 3.
What is the meaning of the word Chennai
Answer:
Face of the city.

TB. PNo: 86
Activity

Question 1.
Find out the coastal districts of Tamil Nadu with the help of a map.
Answer:
13 Districts – Thiruvallur, Chennai, Kaneheepuram, Villupuram, Cuddalore, Tiruvarur, Nagapattinam, Thanjavur, Pudukottai, Ramanathapuram, Thoothukudi, Tirunelveli and Kanyakumari are the coastal districts.

Question 2.
Group the districts of Tamil Nadu which share their boundary with the states of Andhra Pradesh, Karnataka and Kerala separately.
Answer:
Andhra Pradesh – Krishnagiri, Vellore and Tiruvallur.
Karnataka – Krishanagiri. Dharmapuri, Erode, Nilgiris.
Kerala – Nilgiris, Coimbatore, Theni, Tirunelveli, Kanyakumari, Virudhunagar.

TB. PNo: 90
Find Out

Question 1.
Why are mountain heights measured from mean sea level and not from ground level?
Answer:
(i) Ocean is one continuous water body on the earth’s surface. Its surface tend to seek the same level whatever be the landform around.
(ii) It is difficult to establish the base of the mountain from the rest of the ground around as their elevation is not the same on all sides.

Question 2.
Name the hill resorts of Western Ghats and Eastern Ghats in Tamil Nadu.
Answer:
Hill resorts of Western Ghats: Nilgiri hills, Anaimalai, Yelamalai, Varusanadu and Pothigai hills, Megamalai.
Hill resorts of Eastern Ghats: Servarayan hills, Kalvarayan hills, Pachaimalai and Kolli hills.

Question 3.
Is Ooty located on western Ghats?
Answer:
Yes.

Question 4.
Name the hill stations located in Western and Eastern Ghats of Tamil Nadu. Western Ghats:
Answer:
Ooty and coonoor – Nilgiri hills Valparai – Anaimalai hills Kodaikanal -Palani hills Kurangani -Kurangani hills (Theni)
Eastern Ghats:
Yercaud – Servarayan hills

Question 5.
Why is the Nilgiri hills called as Blue Mountains?
Answer:
Nilgiri hills are called as Blue Mountains, inspired by the Kurunji flower which blooms every twelve years giving the slopes a bluish tinge.

TB. PNo: 94
Find Out

Question 1.
What is Agni Nakshatram?
Answer:
Agni Nakshatram period marks the onset of summer season in the month of May – June a period of 21 days. Peak summer with very high temperature, scorching heat all over parts of India.

Question 2.
Group the districts of Tamil Nadu into low, moderate and heavy rainfall regions.
Answer:

Samacheer Kalvi 10th Social Science Physical Geography of Tamil Nadu Additional Important Questions and Answers

I. Choose the correct answer

Question 1.
Initially after bifurcation in Madras State there were only ………………. districts.
(a) 13
(b) 14
(c) 15
(d) 16
Answer:
(a) 13

Question 2.
Tamil Nadu lies in the ……………. part of India.
(a) Northeast
(b) Southwest
(c) Southeast
Answer:
(c) Southeast

Question 3.
Palk Strait and Gulf of Mannar separates Tamil Nadu from :
(a) Andaman and Nicobar Island
(b) Lakshadweep Island
(c) Nepal
(d) Srilanka
Answer:
(d) Srilanka

Question 4.
…………… hill is located in Eastern Ghats.
(a) Nilgiri
(b) Kalrayan
(c) Palani
Answer:
(b) Kalrayan

Question 5.
Tamil Nadu has Loksabha constituencies.
(a) 19
(b) 92
(c) 39
(4)21
Answer:
(c) 39

Question 6.
Mukuruthi is a peak located in the …………….
(a) Eastern Ghats
(b) Nilgiri Hills
(c) Palani Hills
Answer:
(b) Nilgiri Hills

Question 7.
The highest peak in Palani hills is :
(a) Vembadi Shola
(b) Vandaravu
(c) Doddabetta
(d) Ooty
Answer:
(b) Vandaravu

Question 8.
Mangrove forests are found in …………….
(a) Vedaranyam
(b) Coimbatore
(c) Nilgiris
Answer:
(a) Vedaranyam

Question 9.
………………. hills separate Vellore and Tiruvanamalai districts.
(a) Kolli
(b) Andipatti
(c) Pothigai
(d) Javadhu
Answer:
(d) Javadhu

Question 10.
…………. hills seperates Vellore and Thiruvanamali districts.
(a) Pothigai
(b) Andipatti
(c) Javadhu
Answer:
(c) Javadhu

Question 11.
Bharamahal Plateau is a part of ………………. Plateau.
(a) Mysore
(b) Chota Nagpur
(c) Maharashtra
(d) Madurai
Answer:
(a) Mysore

Question 12.
……………. helps in the prevention of coastal erosion from waves and stroms.
(a) Mangroves
(b) trees
(c) Land slide
Answer:
(a) Mangroves

Question 13.
………………. is one of the main tributary of Thamirabarani.
(a) Noyyal
(b) Amaravathi
(c) Moyar
(d) Manimuthar
Answer:
(d) Manimuthar

Question 14.
Tamil Nadu depends mostly on ……………… monsoon.
(a) South west
(b) Northeast
(c) Cyclone
Answer:
(b) Northeast

Question 15.
About ………………… % of the total area of the Tamil Nadu is drought prone.
(a) 26
(b) 62
(c) 64
(d) 46
Answer:
(c) 64

II. Fill in the blanks

1. ………………. is the branch of geography that deals with different physical aspects like landform soil etc.
2. For a short time Tamil country was ruled by the ………………. not much known.
3. Tamil Nadu coast is the second longest in India after ……………….
4. Kallakurichi, Thenkasi and ………………. are the newly formed districts of Tamil Nadu.
5. Our state has ………………. Assembly Constituencies.
6. All districts of Tamil Nadu except the ………………. the Nilgiris and Kanyakumari were bifurcated at different points of time.
7. The Nilgiri hills consists ………………. peaks with more than 2000 metres.
8. ………………. hills are located to the South of Palghat gap.
9. ISRO propulsion complex is situated on the lower slopes of ……………….
10. Vainu Bappu Observatory is in ……………….
11. The Kalvarayan hills separates the river basins of ……………….
12. The name Kalvarayan came from the name of ancient tribes.
13. ………………. temple an important pilgrim centre is located on Kolli hills range.
14. ………………. river separates Coimbatore plateau and Mysore plateau.
15. ………………. is one of the intermontane plateau found in the region of Nilgiri hills.
16. ………………. are found at the head of Gulf of Mannar in the East Coastal regions.
17. The Reservoir of ………………. is called Stanely Reservoir.
18. The network of distributaries of River Cauvery is called ……………….
19. Palar river enters into Bay of Bengal near ……………….
20. The origin of Thamirabarani river is associated with sage ……………….
21. Pre monsoon showers are also known as ………………. showers.
22. Black soil is also known as ……………….
23. ………………. reduces the fertility of the soil.
24. Trees of ………………. forests are economically important.
25. ………………. is the second largest Mangrove forest in the world found in Tamil Nadu.
26. Koonthankulam bird sanctuary is in ………………. district.
27. Pulicat lake bird sanctuary is in ………………. district.
28. A sudden natural catastrophe that causes great damage or less to lives and properties is called ……………….
29. The number of Municipal Corporations in Tamil Nadu is ……………….
30. Ancient Gondwana land broke away 135 years ago during ………………. period.
31. ………………. hills are the eastward extension of Western Ghats.
32. Coastal plains of Tamil Nadu extend from ………………. to ……………….
33. The ………………. coast along the Bay of Bengal consists of many beautiful exotic beaches.
34. ………………. of Tamil Nadu are its life line.
35. Except ………………. river all the other rivers of Tamil Nadu state are non – perennial.
36. Palar river originates beyond ………………. village in Kolar district of Karnataka.
37. The ………………. river is extensively dammed for irrigation especially in Tamil Nadu.
38. The surplus water in Vaigia river is discharged into ………………. tank.
39. The colour of the Red soil is due to the presence of high content of ……………….
40. ………………. soil is suitable for tea and coffee plants.
41. The systematic efforts taken to reduce the risks during disasters is ……………….
42. Water is the most common trigger of a ……………….
43. Tamil nadu was the worst affected state by the flood occured in ……………….

Answers:

1. Physical geography
2. Kalabras
3. Gujarat
4. Chengalpet
5. 234
6. Chennai
7. 24
8. Anaimalai
9. Mahendragiri hills
10. Kavalur
11. Cauvery and Palar
12. Karalar
13. Arapaleeswarar
14. Moyar
15. Slgur
16. Coral rocks
17. Mettur Dam
18. Garden of Southern India
19. Kuvattur
20. Agasthiyar
21. Mango I Blossm
22. Regur soil
23. Soll erosion
24. Tropical Deciduous forest
25. Pichavaram mangrove forest
26. Tirunelveli
27. Trruvallur
28. Disaster
29. 15
30. cretaceous
31. Palam
32. Chennai, Kanyakumari
33. Coromandel Coast
34. Rivers
35. Tharnirabarani
36. Talagavara
37. Then pennaiyar/ Then ponnaiyar
38. Ramnad big tank
39. Iron Oxides
40. Laterite
41. Disaster Risk Reduction
42. landslide
43. 2015

III. Match the following

Question 1.
Match the Column I with Column II.


Answer:
A. (v)
B. (i)
C. (iv)
D. (ii)
E. (iii)

Question 2.
Match the Column I with Column II.

Answer:
A. (iv)
B. (v)
C. (ii)
D. (iii)
E. (i)

Question 3.
Match the Column I with Column II.

Answer:
A. (iii)
B. (v)
C. (iv)
D. (i)
E. (ii)

Question 4.
Match the Column I with Column II.

Answer:
A. (iii)
B. (v)
C. (iv)
D. (i)
E. (ii)

IV. Assertion type question

Question 1.
Assertion (A): Tamil Nadu state was reorganised several times even recently.
Reason (R): For the purpose of administrative convenience.
(a) Both (A) and (R) are true but R does not explain (A).
(b) (A) is true but (R) is false.
(c) (A) is false but(R) is true.
(d) Both (A) and (R) are true and (R) explains (A).
Answer:
(d) Both (A) and (R) are true and (R) explains (A).

Question 2.
Assertion (A): Pothigai hills are called by different names.
Reason (R): It has rich evergreen forest, waterfalls and Ancient temples.
(a) Both (A) and (R) are correct (R) explains (A).
(b) (A) is true but (R) is false.
(c) (A) is false but (R) is true.
(d) Both (A) and (R) are true but (R) does not explains (A).
Answer:
(d) Both (A) and (R) are true but (R) does not explains (A).

Question 3.
Assertion (A): Yercaud is known as poor man’s Ooty.
Reason (R): It is on the Kolli hills.
(a) (A) is true (R) is false
(b) (A) is false (A) is true
(c) Both (A) and (R) are true (R) explains (A).
(d) Both (A) and (R) are true but (R) does not explains (A).
Answer:
(a) (A) is true (R) is false

Question 4.
Assertion (A): Tamil Nadu experiences mild tremor.
Reason(R): The state is located in the moderately low risk seismic zone.
(a) (A) is true (R) is false.
(b) Both (A) and (R) are true (R) explains (A).
(c) (A) is false (R) is true.
(d) Both (A) and (R) are true but (R) does not explains (A).
Answer:
(b) Both (A) and (R) are true (R) explains (A).

V. Answer the following in brief

Question 1.
What do you know about the land features of Tamil Nadu?
Answer:
Tamil Nadu has many unique land features that include high eroded mountains. Shallow deep valleys and plains. The topography of the State slopes towards east.

Question 2.
Mention the Latitudinal and Longitudial extent of Tamil Nadu.
Answer:
Tamil Nadu extends 8° 4′ N to 13° 35′ N latitudes and from 76° 18′ E to 80° 20′ E longitudes.

Question 3.
Name the hills of Western Ghats in Tamil Nadu.
Answer:
The Nilgiris, Anaimalai, Palani hills, Cardomom hills, Varusanadu, Andipatti and Agasthiyar hills.

Question 4.
Name the major physical divisions of Tamil Nadu.
Answer:

• Western Ghats
• Eastern Ghats
• Plateaues
• Coastal plains and
• Inland plains

Question 5.
What are the other names of Pothigai hills?
Answer:
Pothigai hills are called by different names such as Shiva Jothi Parvath, Agasthiyar hills and Southern Kailash.

Question 6.
Name the rivers that flow in the South Of Tamil Nadu?
Answer:

• Vaigai (Madurai)
• Vaippar (Virudhunagar)
• Thamirabarani (Thirunelveli)
• Kodaiyar (Kanyakumari) flows in the south of Tamil Nadu.

Question 7.
What do you mean by Coriolis Force?
Answer:
‘Coriolis Force” refers to the apparent force acts as a result of the earth’s rotation deflects the moving objects (such as projectiles or air currents) to the right in the Northern hemisphere and to the left in the Southern hemisphere. It is one of the main reason for the movement of the monsoon winds originates from the Indian Ocean.

Question 8.
Define Soil.
Answer:

• Soil is a loose material
• It forms the uppermost layer of the earth.
• It is essential for the development of agriculture.

Question 9.
Define soil and its significance.
Answer:
Soil is the loose material mainly formed by the weathering and erosion rocks. It forms an important elements of agriculture. It provides essential minerals and nutrients for the growth vegetation.

Question 10.
Bring out the significance of Kallanai in Tamil Nadu.
Answer:

1. Kallanai built around first century, by Karikalan is still in use.
2. It is considered to be the oldest water regulatory structure in the world.

Question 11.
What are all major factors that control the distribution of natural vegetation?
Answer:
Landforms, nature of the soil, temperature, rainfall and skspe of the relief features are the major factors that control the distribution of natural vegetation.

Question 12.
What is the role played by the mangroves in coastal zone management?
Answer:

1. Mangroves help in the prevention of coastal erosion from waves and storms.
2. It also protects coral reefs and sea grass meadows from being smothered in sediments.

Question 13.
Where the mangrove forests are found in general?
Answer:
In general the mangrove forests are found in the coastal areas, river deltas, tails of islands and over sea faces where accretion is in progress.

Question 14.
Name the places in Tamil Nadu where mangrove forest is found to a considerable extent.
Answer:
Pichavaram, Vedaranyam, Muthupet, Chatram and Thoothukudi are the places in Tamil Nadu where the mangrove forest is found to a considerable extent.

Question 15.
Name the three major Biosphere reservation in Tamil Nadu.
Answer:
The three major Bio – sphere Reservation in Tamil Nadu are:

1. Nilgiris Biosphere Reserve
2. Gulf of Mannar Biosphere Reserve (marine)
3. Agasthiyarmalai Biosphere Reserve

Question 16.
What does Disaster Risk Reduction include?
Answer:
The Disaster Risk Reduction includes:

1. Reducing exposure to hazards.
2. Lessening the vulnerability of people and property.
3. Wise management of land and environment.
4. Improving preparedness and early warning for adverse events.

Question 17.
How does the Government classify the ground water blocks?
Answer:

1. 145 out of 385 are classified as safe ground water blocks.
2. The others are in various stages of depletion such as over exploited, critical and semi-critical.
3. 2% of the blocks are saline and 64% of total area of the state is drought probe.

VI. Distinguish between the following

Question 1.
Distinguish between the plains and plateaus of Tamil Nadu.
Answer:
Plains:

1. Plains of Tamil Nadu is divided into Inland plains and Coastal Plains.
2. Inland plains are formed by the rivers of Tamil Nadu coastal plains are formed along the Bay of Bengal coast by the lower course of the river.
3. Height increases from West to East.
4. It covers the districts of Salem, Erode, Karur, Trichy, Thanjavur, Thiruvarur and Nagapattinam.

Plateaus:

1. Plateaus are subdivided into three – Dharmapuri plateau, Coimbatore plateau and Madurai plateau.
2. Plateaus are oldest region formed by the disintegration of lava rocks and they are located between Western Ghats and Eastern Ghats.
3. Height increases from East to West.
4. Dharmapuri, Krishnagiri, Coimbatore, Nilgiris, Salem and Madurai are the districts lie in the plateau region.

Question 2.
Summer season and winter season in Tamil Nadu.
Answer:
Summer season:

1. Period of summer season begins from March – May.
2. Much variation in summer temperature increases from South to North (30°C – 40°C).
3. Pre monsoon showers and convection rainfall occurs in this season.

Winter season:

1. Period of winter season is from January – February.
2. Not much difference in winter temperature (15°C – 25°C).
3. Generally this season is dry.

Question 3.
Black soil and Alluvial soil.
Answer:
Black soil:

1. Its formation is by weathering of igneous rocks.
2. Clayey in nature when wet develop cracks when dry.
3. Cotton grows well in this soil.
4. It is developed over the Deccan lava granite region under semi arid condition.
5. Found in the districts of Coimbatore, Madurai, Tirunelveli, Virudhunagar.

Alluvial soil:

1. Formed by the deposition of silt by the rivers.
2. Fertile in nature as they are rich in minerals.
3. Paddy and sugar cane grows well in this soil.
4. It is found in the river valley regions and the coastal planis.
5. Found in the districts of Thanjavur, Tiruvarur, Nagapattinam, Cuddalore.

Question 4.
Montane Temperature forest and Tropical Thorn forest.
Answer:
Montane Temperature Forest:

1. Found over an altitude of 1000 mts in sheltered valleys of Anaimalai, Nilgiris and Palani hills.
2. Trees in these forest are evergreen and usually short.
3. Nilgiri champa, wights litsea and rose apple are the common trees.

Tropical Thom Forest:

1. Found where there is little rainfall from plains up to 400 mts altitude.
2. Trees are sturdy and withstand dry condition. Shmbs are common.
3. Palm, neem, rusty acacia, wheel are some of the varieties.

VII. Give reasons for the following

Question 1.
Black soil is also known as Black cotton soil.
Answer:

1. Black soil retails moisture which is very essential for yarning of thread.
2. As cotton grows well in this soil, it is also known as black cotton soil.

Question 2.
It is necessary to conserve the soil resources with intensive care.
Answer:

1. Soil forms the basis mainly for agriculture and other purposes. It is a non-renewable resource and difficult to replace it once it gets degraded.
2. Soil erosion reduces the fertility of the soil which in turn reduces agricultural productivity. So it is necessary to take intensive care to conserve the soil resources.

Question 3.
It is necessary to aware the measures to be adopted during different types of natural disasters.
Answer:
The alteration of natural environment by the technology and developmental activities increase the frequency of disaster all over the world. So it is necessary to aware the measures to be adopted during different types of natural disasters.

Question 4.
Tamil Nadu Government has banned trekking in the state for two months every year (Feb -15 to April 15).
Answer:

1. The high temperature during summer leads to occasional forest fire in deciduous and thorn forests in Tamil Nadu.
2. 23 people were killed as they were stuck in the forest fire at Kurangani hills while trekking. On March 11th, 2018.
3. Thus in the aftermath of this incident made the Tamil Nadu Government to ban trekking for two months during peak summer.

Question 5.
Always avoid roads and bridge during earthquake.
Answer:
Roads may develop crack and bridges may collapse and damaged by the earthquake so we should be causious.

Question 6.
Cardamom hills are also known as Yelamala.
Answer:
The hill acquires its name from the cardamom spice, which is commonly grown here.

VIII. Answer the following in a paragraph

Question 1.
Write about the location and size of Tamil Nadu.
Answer:
Location: Tamil Nadu is located in the Southern most part of the country. It is one among the 29 states of India.

Extent: Latitudinally this land mass extends from 8°4’N to 13°35’N and longitudinally from 76°18’E to 80°20’E longitudes.

Extremities: Its Eastern and Western extremities are defined by the point calimere and the hills of Anaimalai respectively.

The Northern extremity of the state is Pulicate lake and the Southern most point is Cape Comorin.

Area: It covers an area of 1,30,058 sq.km covering 4% of the area of our country.

Size: It is the 11th largest state.

Question 2.
Tabulate the administrative Divisions of Tamil Nadu.
Answer:
The administrative divisions of the Tamil Nadu state are given under.

Division	Number
Districts	35 (32 + 3)
Revenue Divisions	76
Taluks	226
Firkas (Local Revenue Sub-divisions)	1,127
Revenue villages	16,564
Municipal Corporation	15
Municipalities	125
Panchayat Unions (Blocks)	385
Town Panchayats	561
Village Panchayats	12,618
Lok Sabha Constituencies	39
Assembly Constituencies	234

Question 3.
What are the users of forests?
Answer:
Tamil Nadu’s wealth of flora and fauna lies in the hilly and forest regions.

1. Forests are the sanctuaries for wild animals.
2. It provides valuable forest products like Cinchona, Eucalyptus, which are used as medicine for cold, malaria and as a pain reliever.
3. Palmyrah trees are useful for construction works.
4. Forest products are used as raw materials for several cottage industries.
5. Sandalwood is useful for making furniture.
6. These forests not only provide for the large economy of the state but also to the local livelihood.

Question 4.
Give an account of the River Thamirabarani.
Answer:

1. The name is interpreted as Thamiram (copper) Varuni (streams of river).
2. The water of this river gives a copper like appearance due to the presence of dissolved red soil.
3. The river originates from a peak in Pothigai hills on the Western Ghats above Papanasam in the Ambasamudram taluk, (only river originates in Tamil Nadu).
4. The origin of the river is associated with Sage Agasthiyar.
5. It courses through the districts of Tirunelveli and Thoothukudi.
6. It flows into Bay of Bengal near Punnaikayal in Thoothukudi district.
   Tributaries: Karaiyar, Servalar, Manimuthar, Gadananathi, Pachaiyar, Chittar and Ramanathi.
7. It is the only Perennial river of Tamil Nadu as it is fed by both the Southwest and Northeast monsoons.

Question 5.
Write about Pichavaram mangrove forest.
Answer:

1. Pichavaram mangrove forest is located near Chidambaram, Cuddalore district.
2. This is the second largest mangrove forest in the world covering about 1,100 hectares (11 sq.km) of area.
3. It is separated from the Bay of Bengal by a sandbar.
4. It consists of species like Avicennia and Rhizophora.
5. It also supports the existence of rare varieties of shell and fin fishes.

Question 6.
Name any five wild life (Animal) sanctuaries and Bird Sancturies in Tamil Nadu and their location.
Answer:

S.No	Name of the Wildlife Sanctuary	Location
1.	Mudumalai	Nilgiris
2.	Indira Gandhi	Coimbatore
3.	Sathyamangalam	Erode
4.	Grizzled Giant Squirrel	Virudhunagar
5.	Kalakad	Tirunelveli

S.No	Name of the Bird Sanctuary	Location
1.	Pulicat Lake	Tiruvallur
2.	Kanjirankulam	Ramanathapuram
3.	Vedanthangal	Kancheepuram
4.	Koonthankulam-kadankulam	Tirunelveli
5.	Karaivetti	Ariyalur

Question 7.
Write a paragraph on Tropical cyclonic rainfall in Tamil Nadu.
Answer:

1. Tropical cyclones are common during the North – East monsoon season. (October – December)
2. Cyclone originating from Bay of Bengal bring heavy rainfall to the east coastal regions of Tamil Nadu.
3. More than 50% of the state’s rainfall is received from tropical cyclones during this period amount of rainfall.
4. East coastal regions receive 100 to 200 cms of rainfall.
5. Central and North western parts receives 50 – 100 cm of rainfall.
6. The cyclones some times disturb the cultivation of crops and cause severe damage to life and property.

Question 8.
How Tamil Nadu can be classified in to based on cyclone prone zone? Mention the areas of very high and high zone.
Answer:
Based on the cyclone hit areas that ares often hit by the tropical cyclone formed in Bay of Bengal during Northeast monsoon season. Tamil Nadu is classified into five zones. Namelys

Very high, high, medium, low and veiy low cyclone prone zone.

Areas:
Very high zone: Southern part of Chennai, Eastern part of Kanchipuram and Villupuram, North Eastern part of Cuddalore and Union territory of Puduchery.

High zone: Nagapattinam, Thiruvallur, Tiruvarur (except North Western part) Southern part of Tanjavur, Eastern part of Pudukottai, Cuddalore, Tiruvannamalai, North Eastern part of Vellore, Northern part of Chennai, North Western part to Kanchipuram and Middle portion of Villupuram.

Question 9.
How can we manage water scarcity? Suggest some methods of water conservation.
Answer:

1. Tamil Nadu is water deficit state.
2. To manage water deficit, rain water harvesting and water conservation methods have to be implemented strictly.

Methods of water conservation:

1. Protect water conservation.
2. Rational use of ground water.
3. Renovation of traditional water source.
4. Increasing forest cover.
5. Recycling of water for other uses.
6. Changing crop pattern.
7. Flood management.
8. Use of geo-thermal water.

IX. Map study

Question 1.
On the given map of Tamil Nadu mark the following.
Answer:
(a) (i) Boundaries of Tamil Nadu
(ii) Capital of Tamil Nadu and its District.

Districts: (i) Any two coastal districts on the east
(ii) Kanyakumari, Cape Comorin, Nilgiris, Vellore
(iii) Pulicate lake.

(b)

1. Gulf of Mannar
2. Palk Strait
3. Palk Bay
4. Pamban
5. Rameswaram
6. Coromandel coast
7. Kaveri plains
8. Dharmapuri
9. Kollidam
10. Mettur Dam

(c)

1. Ooty
2. Kodaikanal
3. Doddabetta
4. Mukurti lake
5. Sathuragiri
6. Perumalmalai
7. Palani hills
8. Javadhi hills
9. Elagiri
10. Point calimere
11. Agathiyamalai

Students can download 10th Science Chapter 17 Reproduction in Plants and Animals Questions and Answers, Notes, Samacheer Kalvi 10th Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 17 Reproduction in Plants and Animals

Samacheer Kalvi 10th Science Reproduction in Plants and Animals Text Book Back Questions and Answers

I. Choose the correct answer:

Question 1.
The plant which propagates with the help of its leaves is:
(a) Onion
(b) Neem
(c) Ginger
(d) Bryophyllum
Answer:
(d) Bryophyllum

Question 2.
Asexual reproduction takes place through budding in ______.
(a) Amoeba
(b) Yeast
(c) Plasmodium
(d) Bacteria.
Answer:
(b) Yeast

Question 3.
Syngamy results in the formation of:
(a) Zoospores
(b) Conidia
(c) Zygote
(d) Chlamydospores
Answer:
(c) Zygote

Question 4.
The essential parts of a flower are ______.
(a) Calyx and Corolla
(b) Calyx and Androecium
(c) Corolla and Gynoecium
(d) Androecium and Gynoecium.
Answer:
(d) Androecium and Gynoecium.

Question 5.
Anemophilous flowers have:
(a) Sessile stigma
(b) Small smooth stigma
(c) Colored flower
(d) Large feathery stigma
Answer:
(d) Large feathery stigma

Question 6.
Male gametes in angiosperms are formed by the division of ______.
(a) Generative cell
(b) Vegetative cell
(c) Microspore mother cell
(d) Microspore.
Answer:
(a) Generative cell

Question 7.
What is true of gametes?
(a) They are diploid
(b) They give rise to gonads
(c) They produce hormones
(d) They are formed from gonads
Answer:
(d) They are formed from gonads

Question 8.
A single highly coiled tube where sperms are stored, get concentrated and mature is known as ______.
(a) Epididymis
(b) Vasa efferentia
(c) Vas deferens
(d) Seminiferous tubules.
Answer:
(d) Seminiferous tubules.

Question 9.
The large elongated cells that provide nutrition to developing sperms are:
(a) Primary germ cells
(b) Sertoli cells
(c) Leydig cells
(d) Spermatogonia
Answer:
(b) Sertoli cells

Question 10.
Estrogen is secreted by ______.
(a) Anterior pituitary
(b) Primary follicle
(c) Graafian follicle
(d) Corpus luteum.
Answer:
(b) Primary follicle

Question 11.
Which one of the following is an IUCD?
(a) Copper – T
(b) Oral pills
(c) Diaphragm
(d) Tubectomy
Answer:
(a) Copper – T

II. Fill in the blanks:

1. The embryo sac in a typical dicot at the time of fertilization is ………
2. After fertilization the ovary develops into ………
3. Pianaria reproduces asexuallv by ………
4. Fertilization is ……….. in humans.
5. The implantation of the embryo occurs at about ……….. day of fertilization.
6. ………. is the first secretion from the mammary gland after child birth.
7. Prolactin is a hormone produced by …………

Answer:

1. Double fertilization
2. Fruits
3. Regeneration
4. Internal
5. 6 to 7
6. Colostrum
7. Anterior pituitary

III. Match the following:

Question 1.

Answer:
A. (ii)
B. (iii)
C. (i)

Question 2.
Match the following terms with their respective meanings

Answer:
A. (iii)
B. (i)
C. (iv)
D. (ii)

IV. State whether the following statements are True or False. Correct the false statement.

1. Stalk of the ovule is called pedicle.
2. Seeds are the product of asexual reproduction.
3. Yeast reproduces asexually by means of multiple fission.
4. The part of the pistil which serves as a receptive structure for the pollen is called as style.
5. Insect pollinated flowers are characterized by dry and smooth pollen.
6. Sex organs produce gametes which are diploid.
7. LH is secreted by the posterior pituitary.
8. Menstrual cycle ceases during pregnancy.
9. Surgical methods of contraception prevent gamete formation.
10. The increased level of oestrogen and progesterone is responsible for menstruation.
Answer:
1. False – Stalk of the ovule is called Funiculus
2. False – Seeds are the product of sexual reproduction
3. False – Budding reproduces asexually by means of multiple fission.
4. False – The part of the pistil which serves as a receptive structure or the pollen is called as stigma.
5. False – Wind pollinated flowers are characterized by dry and smooth pollen.
6. False – Sex organs produce gametes which are haploid
7. False – Anterior pituitary (LH is secreted by the Anterior pituitary)
8. True
9. True
10. True

V. Answer in a word or sentence.

Question 1.
If one pollen grain produces two male gametes, how many pollen grains are needed to fertilize 10 ovules?
Answer:
Atleast 10 pollen grains required to fertilise 10 ovules because only one male gamete is involved in the fusion of male gamete with the egg cell.

Question 2.
In which part of the flower germination of pollen grains takes place?
Answer:
Pollen grains reach the stigma and begin to germinate.

Question 3.
Name two organisms which reproduces through budding.
Answer:
Yeast and hydra reproduce through budding.

Question 4.
Mention the function of the endosperm.
Answer:
The endosperm provides food to the developing embryo.

Question 5.
Name the hormone responsible for the vigorous contractions of the uterine muscles.
Answer:
Oxytocin from the posterior pituitary stimulates the uterine contraction.

Question 6.
What is the enzyme present in the acrosome of sperm?
Answer:
Hyaluronidase is the enzyme, present in the acrosome of sperm, which helps the sperm to enter the ovum during fertilization.

Question 7.
When is World Menstrual Hygiene Day observed?
Answer:
Every year May 28th is observed as Menstrual Hygiene day to make girls and women aware of maintaining menstrual hygiene and importance of menstrual hygiene for good health.

Question 8.
What is the need for contraception?
Answer:
Contraception is used to prevent pregnancy, to check population growth.

Question 9.
Name the part of the human female reproductive system where the following occurs, (a) Fertilization (b) Implantation
Answer:
(a) Fertilization: Occurs in the oviduct of the female genital tract. It takes place usually in the ampulla of the fallopian tube.
(b) Implantation: Blastocyst reaches the uterus (uterine wall) (endometrium)

VI. Short Answer Questions

Question 1.
What will happen if you cut planaria into small fragments?
Answer:
Each fragment will develop into a new individual by a specialized mass of cell. It is called regeneration. It is the ability of the lost body parts of an individual organism to give rise to a whole new organism.

Question 2.
Why is vegetative propagation practised for growing some type of plants?
Answer:
The vegetative part of plant, root, stem, leaf or budgets detached from the parent body and grows into an independent daughter plant by mitotic division. The daughter plants are genetically similar to the parent plant.

Question 3.
How does binary fission differ from multiple fission?
Answer:

Question 4.
Define triple fusion.
Answer:
The fusion involving two polar nuclei and a sperm nucleus, that occurs in double fertilization in a seed plant and results in the formation of endosperm, is called the triple fusion.

Question 5.
Write the characteristics of insect-pollinated flowers.
Answer:

1. The flowers are brightly coloured to attract insects which have smell and nectar.
2. The pollen grains are larger in size, the exine is pitted, spiny, so they can be adhered firmly on the stucky stigma.

Question 6.
Name the secondary sex organs in male.
Answer:
The secondary sex organs in the male are vas deferens, Epididymis, seminal vesicle, prostate gland and penis.

Question 7.
What is colostrum? How is milk production hormonally regulated?
Answer:
The milk produced from the breast during the first 2 to 3 days after child birth is called colostrum. Milk production from alveoli of mammary glands is stimulated by prolactin secreted from the anterior pituitary.

Question 8.
How can menstrual hygiene be maintained during menstrual days?
Answer:
Maintaining menstrual hygiene is important for the overall health of women.

• Sanitary pads should be changed regularly, to avoid infections due to microbes from vagina and sweat from genitals.
• Use of warm water to clean genitals, to get rid of menstrual cramps.
• Wearing loose clothing, to ensure the airflow around the genitals, to prevent sweating.

Question 9.
How does developing embryo gets its nourishment inside the mother’s body?
Answer:
The developing embryo gets nutrition from the mother’s blood with the help of a special tissue called placenta. It is embedded in the uterine wall. This is a disc like tissue which develops between the uterine walls and embryo. It has villi of embryo side of the tissue. On the mother side are blood spaces with the villi. This gives a large surface area for oxygen and glucose to pass from the mother to the embryo.

Question 10.
Identify the parts A, B, C and D.

Answer:
A – Exine
B – Intine
C – Generative nucleus
D – Vegetative nucleus

Question 11.
Write the events involved in the sexual reproduction of a flowering plant.

1. Discuss the first event and write the types.
2. Mention the advantages and disadvantages of that event.

Answer:

1. The transfer of pollen grains from the anther to the stigma of a flower is called pollination. Self – Pollination and Cross-Pollination are the two types of Pollination.
2. Advantages:
   • It results in fertilization, which leads to the formation of fruits and seeds.
   • New varieties of plants are formed, through a new combination of genes,
3. Disadvantages:
   • More wastage of pollen grains.
   • Pollination may fail due to the distance barrier.
   • Flowers depend on external agencies for pollination.

Question 12.
Why are the human testes located outside the abdominal cavity? Name the pouch in which they are present.
Answer:
Human testes responsible for synthesis of male gametes(sperms) need slightly lower temperature than the normal body temperature for this function. Thus, they are located outside the abdominal cavity in a sac like structure called scrotum.

Question 13.
The luteal phase of the menstrual cycle is also called the secretory phase. Give reason.
Answer:
During the Luteal phase of the menstrual cycle in the uterus, the hormone progesterone is produced by the ovaries. Progesterone and estrogen are secreted by the Corpus Luteum, which develops from the Graafian follicle. So this phase of the menstrual cycle is called the secretory phase.

Question 14.
Why are family planning methods not adopted by all the people of our country?
Answer:
Family planning is a way of living that is adopted voluntary by couples on the basis of knowledge and responsible decision to promote the health and welfare of the family group and society. As it is voluntary many people are not aware of the importance of family planning.

VII. Long Answer Questions.

Question 1.
With a neat labelled diagram describe the parts of a typical angiospermic ovule.
Answer:
Structure of the Ovule : The main part of the ovule is the nucellus which is enclosed by two integuments leaving an opening called as micropyle. The ovule is attached to the ovary wall by a stalk known as funiculus. Chalaza is the basal part.

The embryo sac contains seven cells and the eighth nuclei located within thenucellus. Three cells at the micropylar end form the egg apparatus and the three cells at the chalaza end are the antipodal cells. The remaining two nuclei are called polar nuclei found in the centre. In the egg apparatus one is the egg cell (female gamete) and the remaining two cells are the synergids.

Question 2.
What are the phases of menstrual cycle? Indicate the changes in the ovary and uterus.
Answer:

VIII. Higher Order Thinking Skills: (HOTS)

Question 1.
In angiosperms, the pollen germinates to produce a pollen tube that carries two gametes. What is the purpose of carrying two gametes when single gamete can fertilize the egg?
Answer:
One sperm fuses with the egg (syngamy) and forms a diploid zygote. The other sperm fuses with the secondary nucleus (Triple fusion) to form the primary endosperm. After triple fusion, the primary endosperm nucleus develops into an endosperm. The purpose of carrying two gametes is, endosperm provides food to the developing embryo.

Question 2.
Why menstrual cycle does not take place before puberty and during pregnancy?
Answer:
Menstruation occur when the egg is not fertilized. Every month uterus prepares itself to receive the fertilized egg to nourish the embryo, its lining becomes thick and spongy for implantation of the fertilized egg.
In case egg is not fertilized thin lining breaks and discharged out of the body through the vagina in the form of blood.
This condition will not happen before puberty and during pregnancy.

Question 3.
Read the following passage and answer the questions that follow:
Rohini and her parents were watching a television programme. An advertisement flashed on the screen which was promoting the use of sanitary napkins. Rohini’s parents suddenly changed the channel, but she objected to her parents and explained the need and importance of such advertisement.
(a) What is first menstruation called? When does it occur?
(b) List out the napkin hygiene measures taken during menstruation?
(c) Do you think that Rohini’s objection towards her parents was correct? If so, Why?
Answer:
(a) The first period or menstruation is a point in time, known as Menarche. It usually begins between 12 to 15 years of age.

(b)

1. The sanitary pad and tampons should be wrapped properly and discarded because they can spread infections.
2. Sanitary pad or tampon should not be flushed down the toilet.
3. Napkin incinerators are to be used properly for disposal of used Napkins.

(c) No, it was not correct. The parents and teachers have to create awareness among the school girls about the use of Napkins and their proper disposal. Girls should be educated and should know the importance of such advertisement on Television.

Samacheer Kalvi 10th Science Reproduction in Plants and Animals Additional Important Questions and Answers

I. Choose the correct answer:

Question 1.
In a pollen grain the small nucleus is:
(a) Generative nucleus
(b) Tube nucleus
(c) Vegetative nucleus
(d) Pollen nucleus
Answer:
(a) Generative nucleus

Question 2.
The female part of the flower is ______.
(a) Androecium
(b) Anemophily
(c) Gynoecium
(d) Micropyle.
Answer:
(c) Gynoecium

Question 3.
Spirogyra is an:
(a) Virus
(b) Fungi
(c) Bacteria
(d) Algae
Answer:
(d) Algae

Question 4.
During pregnancy, the uterus expands, it’s normal size up to ______.
(a) 200 times
(b) 500 times
(c) 600 times
(d) 800 times.
Answer:
(b) 500 times

Question 5.
In wind pollinated flowers, the pollen grains are:
(a) sticky and powdery
(b) small and powdery
(c) dry and powdery
(d) wet and powdery
Answer:
(c) dry and powdery

Question 6.
Androecium is the part of the flower.
(a) upper
(b) male
(c) lower
(d) female
Answer:
(b) male

Question 7.
Zygote is a resulting product of:
(a) Germination
(b) Pollination
(c) Fusion of Embryosac
(d) Fertilization
Answer:
(d) Fertilization

Question 8.
Pick out the correct statement:
(a) Endosperm is a connective tissue
(b) Endosperm is a muscular tissue
(c) Endosperm is a nutritive tissue
(d) Endosperm is a nervous tissue
Answer:
(c) Endosperm is a nutritive tissue

Question 9.
The follicle that ruptures at the time of ovulation promptly fills with blood, forming:
(a) Corpus Luteum
(b) Corpus albricans
(c) Corpus Collosum
(d) Corpus Haemorrhagueim
Answer:
(a) Corpus Luteum

Question 10.
The endometrium is the lining of:
(a) bladder
(b) vagina
(c) uterus
(d) oviduct
Answer:
(c) uterus

Question 11.
Menstrual flow occurs due to lack of:
(a) Progesterone
(b) FSH
(c) Oxytocin
(d) Vasopressin
Answer:
(a) Progesterone

Question 12.
Testosterone is secreted by:
(a) Leydig cells
(b) Sertoli cells
(c) Seminiferous tubule
(d) None of these
Answer:
(d) None of these

Question 13.
In mammals, maturation of sperms take place at a temperature:
(a) Equal to that of body
(b) Higher than that of body
(c) Lower than that of body
(d) At any piece of mammalian sperm
Answer:
(c) Lower than that of body

Question 14.
If menstrual cycle is 30 days and bleeding starts on 1st day, then ovulation occur on:
(a) 14th day
(b) 18th day
(c) 30th day
(d) 16th day
Answer:
(d) 16th day

Question 15.
The symbol of family planning in India is:
(a) Square
(b) Inverted red triangle
(c) Rectangle
(d) Circle
Answer:
(b) Inverted red triangle

II. Fill in the blanks.

1. Purpose of tubectomy is to prevent ………
2. Progesterone is secreted by ………..
3. Sertoli cells are found mg in ………….
4. Hormone responsible for ovulation and development of corpus luteum is ………..
5. First menstrual cycle starts is ………..
6. The functional maturation of sperms takes place in ………..
7. Seeds develops from …………
8. In ……… buds are produced in the notches along the leaf margin.
9. Androecium is a group of …………
10. In self pollination, flowers need not to depend on ………… of pollination.
11. Pollination by wind is called ………..
12. The point of attachment of ovule to the funicle is known as …………..
13. In Angiosperm pollen tube liberate their male gametes into the …………
14. Double fertiliztaion is essential for formation of ……….
15. During spore formation a structure called ………… develops from the fungal hypha
Answer:
1. Fertilization
2. Corpus luteum
3. Seminiferous tubule
4. LH
5. Menarche
6. Epididyms
7. Ovule
8. Bryophyllum
9. Stamens
10. Agents
11. Anemophily
12. Hilum
13. Synergids
14. Endosperm
15. Sporangium

III. Match the following

Question 1.
Match the Column I with Column II.

Answer:
A. (v)
B. (i)
C. (ii)
D. (iii)
E. (iv)

Question 2.
Match the Column I with Column II

Answer:
A. (ii)
B. (i)
C. (iv)
D. (v)
E. (iii)

IV. Assertion and Reasoning:

Direction: In each of the following questions a statement of assertion (A) is given and a corresponding statement of reason (R) is given just below it. Mark the correct statement as.
Question 1.
Assertion (A): Some of the Angiospermic plants are propagated only by vegetative propagation.
Reason (R): They have lost the capacity of seed formation.
(a) If both A and R are true and R is correct explanation of A.
(b) If both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) Both A and R are false.
Answer:
(a) If both A and R are true and R is correct explanation of A.

Question 2.
Assertion (A): Double fertilization is the universal features of all plants.
Reason (R): In this fusion only male gametes and secondary nucleus takes place.
(a) If both A and R are true and R is correct explanation of A.
(b) If both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) Both A and R are false.
Answer:
(d) Both A and R are false.

Question 3.
Assertion (A): The unit of Androecium is called stamen.
Reason (R): The most important part of androecium is anther.
(a) If both A and R are true and R is correct explanation of A.
(b) If both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) Both A and R are false.
Answer:
(c) A is true but R is false.

Question 4.
Assertion (A): Anemophily includes wastage of pollen grains.
Reason (R): Anemophilous flowers are neither attractive nor fragrant.
(a) If both A and R are true and R is correct explanation of A.
(b) If both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) Both A and R are false.
Answer:
(b) If both A and R are true but R is not the correct explanation of A.

Question 5.
Assertion (A): Sexual reproduction takes place with the participation of two different type of gametes.
Reason (R): Sexual reproduction is also known as Apomixies.
(a) If both A and R are true and R is correct explanation of A.
(b) If both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) Both A and R are false.
Answer:
(c) A is true but R is false.

Question 6.
Assertion (A): In India, IUDS most widely accepted methods of contraception.
Reason (R): IUDS are injectable contraceptives, which prevent pregnancy for three months.
(a) If both A and R are true and R is correct explanation of A.
(b) If both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) Both A and R are false.
Answer:
(c) A is true but R is false.

Question 7.
Assertion (A): Over population has become a serious problem in developing countries.
Reason (R): It may exhaust natural resources, cause unemployment and lead to pollution.
(a) If both A and R are true and R is correct explanation of A.
(b) If both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) Both A and R are false.
Answer:
(a) If both A and R are true and R is correct explanation of A.

V. State whether True or false, If false write the correct statement

1. Tubectomy a method of population control performed on males.
2. Oral pills are very popular contraceptives among the rural women.
3. The germ pore of dicot seed is known as micropyle.
4. Vegetative reproduction is a kind of asexual reproduction.
5. The protective wall of the pollen is intine.

Answer:

1. False – Tubectomy a method of population control performed on females
2. False – Oral pills are very popular contraceptives among the urban women
3. True
4. True
5. False – The protective wall of the pollen is exine.

VI. Answer in a word or sentence:

Question 1.
Define reproduction.
Answer:
Reproduction is the process of producing offspring of their own kind.

Question 2.
Define Fertilization.
Answer:
The fusion of male gamete with female gamete to form zygote is called fertilization.

Question 3.
Where the fertilization takes place in human female?
Answer:
Fertilization in human female occurs in the oviduct of the female genetal tract. It takes place usually in the ampulla of the fallopian tube.

Question 4.
Name two types of reproduction.
Answer:
Asexual and Sexual reproduction.

Question 5.
Define Menstruation.
Answer:
Menstruation is a periodical phenomenon that continues from puberty to menopause. This will happen if the released ovum is not fertilized by the sperm.

Question 6.
Write the name of male and female reproductive part of a flower.
Answer:
Androecium and Gynoecium.

Question 7.
Define gestation period.
Answer:
Gestation is the time period during which the embryo attains its development in the uterus.

Question 8.
What is the gestation period in human?
Answer:
Normally gestation period of human last for about 280 days.

Question 9.
Write the full form of IUD and AIDS.
Answer:
IUD – Intra Uterine devices
AIDS – Acquired Immuno Deficiency Syndrome

Question 10.
What is Menopause?
Answer:
A natural decline in reproductive hormones when a woman reaches 48-50 years of age.

Question 11.
Define Pollination.
Answer:
The transfer of pollen grains from anther to stigma of a flower is called pollination.

Question 12.
What are the agents of pollination?
Answer:
Animals, Insects, Wind and Water are the agents of Pollination.

Question 13.
What is Parturition?
Answer:
Parturition is the expulsion of young one from the mother uterus at the end of gestation.

Question 14.
What is endometrium?
Answer:
The endometrium is the inner epithelial layer along with its mucous membrane of the mammalian uterus.

Question 15.
What are gonads?
Answer:
Organs of the reproductive system are gonads. Testes are male gonads and ovaries are female gonads.

Question 16.
Name two sexually transmitted disease.
Answer:
Syphilis. AIDS

Question 17.
What is Vitelline membrane?
Answer:
The membrane forming the surface layer of the ovum is called vitelline membrane.

Question 18.
Which parts of the flower transform into the seed and fruit?
Answer:
Ovule develops into seed.
Ovary develops into fruit.

Question 19.
Name two sex hormones.
Answer:
Testosterone and Progesterone

Question 20.
What is umblical cord?
Answer:
A cord containing blood vessels that connects the placenta with the foetus is called the umblical cord.

VII. Short Answer Questions

Question 1.
What is vegetative reproduction? Give an example.
Answer:
New plantlets, which are formed from the vegetative (somatic) parts of plants, such as root, stem, leaf or bud from the parent body is called vegetative reproduction, eg. In Bryophyllum, small plants grow at the leaf notches.

Question 2.
What happens when the egg is not fertilized?
Answer:
If the egg is not fertilized, corpus luteum degenerates, the egg disintegrates and the uterine lining slowly breaks, discharges as blood and mucus leading to menstrual events.

Question 3.
Explain the types of Urinary Tract Infection?
Answer:
Woman are susceptible to Urinary Tract Infection from the bacteria, that are present on skin, rectum or vagina. The types of UTI are:

• Cystitis or Bladder infection: Bacteria lodged in the urinary bladder, thrive and multiply leading to inflammation, at the age group of 20 to 50.
• Kidney Infection: The bacteria travels from the urinary bladder and upward to ureter and affect one or both the kidneys. It also infects the bloodstream and leads to serious life-threatening complications.
• Asymptomatic Bacteriuria: The bacteria present in the urinary bladder, which may not show any symptoms.

Question 4.
How does reproduction help in providing stability to population of species?
Answer:
Reproductive ensures the continuity and survival of the species. This process is to preserve individual species and it is called self perpetuation.

Question 5.
What is vegetative propagation? Write two examples where it is used.
Answer:
In vegetative propagation, new plantlets are formed from vegetative cells, buds or organs of plant. The vegetative part of plant get detached from the parent body and grow into an independent daughter plant. Root – Sweet potato, Stem – Strawberry.

Question 6.
What could be the reasons for adopting contraceptive methods?
Answer:

1. To avoid frequent pregnancies, which in turn helps in population control.
2. To prevent the spread of sexually transmitted diseases.

Question 7.
State in brief the function of the following organ,
(a) Ovary
(b) Fallopian tube
Answer:
(a) Ovary – Produce Oocytes (egg) for fertilization and produce hormones – Oestrogen and Progesterone.
(b) Fallopian tube – Transport the egg from the ovary to uterus.

Question 8.
Surgical methods can be used to create a block in the reproductive system for contraceptive purpose. Name such parts where block are created in
(i) Male
(ii) Female.
Answer:
(i) Male – Vasectomy – ligation of vas deferens
(ii) Female – Tubectomy – ligation of Fallopian tube

VIII. Long Answer Questions

Question 1.
List out the different methods of contraceptive. Explain any two.
Answer:
Common contraceptive methods used to prevent pregnancy are:
(i) Barrier methods
(ii) Hormonal methods
(iii) Intra-Uterine Devices (IUDs)
(iv) Surgical methods

(i) Barrier Methods : This method prevents sperms from meeting the ovum. Its entry into the female reproductive tract is prevented by barrier.

1. Condom : Condom prevents deposition of sperms in the vagina. Condoms are made of thin rubber or latex sheath. Condom also protect against sexually transmitted diseases (STD) like syphilis, AIDS.
2. Diaphragm (Cervical cap) : Vaginal diaphragm fitting into the vagina or a cervical cap fitting over the cervix. This prevents the entry of sperms into the uterus.

(ii) Hormonal Methods : Hormonal preparations are in the form of pills or tablets (contraceptive pills). These hormones stop (interfere with ovulation) the release of egg from the ovary.

Question 2.
Explain the structure of pollen grain with a labelled diagram.
Answer:
Pollen grains are usually spherical in shape. It has two layered wall. The hard outer layer is known as exine. It has prominent apertures called germpore. The inner thin layer is known as intine. It is a thin and continuous layer made up of cellulose and pectin. Mature pollen grains contain two cells, the vegetative and the generative cell. Vegetative cell contains a large nucleus. The generative cell divides mitotically to form two male gametes.

Question 3.
Write the advantages and disadvantages of self and cross pollination.
Answer:
Advantages of self-pollination:

1. Self-pollination is possible in certain bisexual flowers.
2. Flowers do not depend on agents for pollination.
3. There is no wastage of pollen grains.

Disadvantages of self-pollination:

1. The seeds are less in numbers.
2. The endosperm is minute. Therefore, the seeds produce weak plants.
3. New varieties of plants cannot be produced.

Advantages of cross pollination:

1. The seeds produced as a result of cross pollination, develop and germinate properly and grow into better plants, i.e., cross pollination leads to the production of new varieties.
2. More viable seeds are produced.

Disadvantages of cross-pollination:

1. Pollination may fail due to distance barrier.
2. More wastage of pollen grains.
3. It may introduce some unwanted characters.
4. Flowers depend on the external agencies for pollination.

Question 4.
Explain the structure of human sperm with diagram.
Answer:

Structure of Human Sperm: The spermatozoan consists of head, a middle piece and tail. The sperm head is elongated and formed by the condensation of nucleus. The anterior portion has a cap like structure called acrosome. It contains hyaluronidase an enzyme that helps the sperm to enter the ovum during fertilization. A short neck connects the head and middle piece which comprises the centrioles. The middle piece contains the mitochondria which provides energy for the movement of tail. It brings about sperm motility which is essential for fertilization.

Question 5.
Explain the structure of ovum with diagram.
Answer:
The mature ovum or egg is spherical in shape. The ovum is almost free of yolk. It contains abundant cytoplasm and the nucleus. The ovum is surrounded by three membranes. The plasma membrane is surrounded by inner thin zona pellucida and an outer thick corona radiata. The corona radiata is formed of follicle cells. The membrane forming the surface layer of the ovum is called vitelline membrane. The fluid-filled space between zona pellucida and the surface of the egg is called perivitelline space.

IX. Give Reason:

Question 1.
If a women is using copper – T, will it help in protecting her from sexual transmitted diseases?
Answer:
No, Copper-T does not prevent the transmission of sexually transmitted diseases. Copper-T only prevents implantation. The only safe method used to prevent the transmission of sexually transmitted diseases is the use of condoms.

Question 2.
Leaves of the Bryophyllum fallen on the ground produce new plants whereas the leaves of rose do not. Why?
Answer:
The leaves of Bryophyllum is levoad and fleshy, has notches at its margins. Buds arise from the notches, but in rose plant notches are absent.

Question 3.
The organisms formed by asexual reproduction are considered as clones. Why?
Answer:
Offspring produced by a asexual reproduction are not only identical to parents, but are also exact copies of their parent because it involves only miotic cell division.

X. Higher Order Thinking Skills (HOTS)

Question 1.
Organism A needs water to multiply and organism B needs sugar solution to multiply. Identify the organism A and B and their method of Reproduction.
Answer:
Organism A is Amoeba – which multiplies by binary fusion.
Organism B is Yeast – which needs sugar medium for budding.

Question 2.
If ovaries from a pregnant woman arc removed in 4th month of pregnancy. What will happen?
Answer:
Embryo develops normally till birth as it grows in the utreus.

Question 3.
A pregnant female not able to delivers the baby due to lack of ‘X’ hormones. Identify ‘X’ hormone. Write its function.
Answer:
The ‘X” hormone is oxytocin. It provides force to expel the baby from the uterus causing birth.

Students can download 10th Science Chapter 15 Nervous System Questions and Answers, Notes, Samacheer Kalvi 10th Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 15 Nervous System

Samacheer Kalvi 10th Science Nervous System Text Book Back Questions and Answers

I. Choose the correct answer:

Question 1.
Bipolar neurons are found in:
(a) retina of eye
(b) cerebral cortex
(c) embryo
(d) respiratory epithelium
Answer:
(a) retina of eye

Question 2.
The site for processing of vision, hearing, memory, speech, intelligence, and thought is ______
(a) kidney
(b) ear
(c) brain
(d) lungs
Answer:
(c) brain

Question 3.
In reflex action, the reflex arc is formed by:
(a) brain, spinal cord, muscle
(b) receptor, muscle, spinal cord
(c) muscle, receptor, brain
(d) receptor, spinal cord, muscle
Answer:
(d) receptor, spinal cord, muscle

Question 4.
Dendrites transmit impulse ______ cell body and axon transmit impulse ______ cell body.
(a) away from, away from
(b) towards, away from
(c) towards, towards
(d) away from, towards
Answer:
(b) towards, away from

Question 5.
The outer most of the three cranial meninges is:
(a) arachnoid membrane
(b) piamater
(c) duramater
(d) myelin sheath
Answer:
(c) duramater

Question 6.
There are …….. pairs of cranial nerves and ………. pairs of spinal nerves.
(a) 12, 31
(b) 31, 12
(c) 12, 13
(d) 12, 21
Answer:
(a) 12, 31

Question 7.
The neurons which carries impulse from the central nervous system to the muscle fibre _____
(a) afferent neurons
(b) association neuron
(c) efferent neuron
(d) unipolar neuron
Answer:
(c) efferent neuron

Question 8.
Which nervous band connects the two cerebral hemispheres of brain?
(a) thalamus
(b) hypothalamus
(c) corpus callosum
(d) pons
Answer:
(c) corpus callosum

Question 9.
Node of Ranvler is found in:
(a) muscles
(b) axons
(c) dendrites
(d) cyton
Answer:
(b) axons

Question 10.
Vomiting centre is located in ______
(a) medulla oblongata
(b) stomach
(c) cerebrum
(d) hypothalamus
Answer:
(a) medulla oblongata

Question 11.
Nerve cells do not possess:
(a) neurilemma
(b) sareolemma
(c) axon
(d) dendrites
Answer:
(b) sareolemma

Question 12.
A person who met with an accident lost control of body temperature, water balance, and hunger. Which of the following part of the brain is supposed to be damaged?
(a) medulla oblongata
(b) cerebrum
(c) pons
(d) hypothalamus
Answer:
(d) hypothalamus

II. Fill in the blanks:

1. ……….. is the longest cell in our body.
2. Impulses travels rapidly ……….. in ……….. neurons.
3. A change in the environment that causes an animal to react is called ………..
4. ………. carries the impulse towards the cell body.
5. The two antagonistic component of autonomic nervous system are ……….. and ……….
6. A neuron contains all cell organelles except …………
7. ………. maintains the constant pressure inside the cranium.
8. ………… and ………… increases the surface area of cerebrum.
9. The part of human brain which acts as relay center is ………….

Answer:

1. Nerve cell or neuron
2. sensory
3. stimulus
4. Dentrites
5. sympathetic and parasympathetic system
6. Nucleus
7. Cerebro Spinal Fluid (CSF)
8. Gyri and sulci
9. thalamus

III. State whether true or false, if false write the correct statement:

1. Dendrons are the longest fibres that conducts impulses away from the cell body.
2. Sympathetic nervous system is a part of central nervous system.
3. Hypothalamus is the thermoregulatory centre of human body.
4. Cerebrum controls the voluntary actions of our body.
5. In the central nervous system myelinated fibres form the white matter.
6. All the nerves in the body are covered and protected by meninges.
7. Cerebrospinal fluid provides nutrition to brain.
8. Reflex arc allows the rapid response of the body to a stimulus.
9. Pons helps in regulating respiration.

Answer:

1. False – Axons are the longest fibres that conducts impulses away from the cell body.
2. False – Autonomic nervous system is a part of central nervous system.
3. True
4. False – Cerebellum controls the voluntary actions of our body.
5. True
6. False – Brain is covered and protected by meninges.
7. True
8. True
9. True

IV. Match the following:

Answer:
A. (iii)
B. (i)
C. (iv)
D. (ii)

V. Understand the assertion statement. Justify the reason given and choose the correct choice:

(a) Assertion is correct and reason is wrong.
(b) Reason is correct and the assertion is wrong.
(c) Both assertion and reason are correct.
(d) Both assertion and reason are wrong.
1. Assertion: Cerebrospinal fluid is present throughout the central nervous system.
Reason: Cerebrospinal fluid has no such functions.
Answer:
(a) Assertion is correct and reason is wrong.

2. Assertion: Corpus callosum is present in space between the duramater and . piamater.
Reason: It serves to maintain the constant intracranial pressure.
Answer:
(d) Both assertion and reason are wrong.

VI. Short Answer Questions:

Question 1.
Define the stimulus.
Answer:
The changes in the environmental condition that are detected by the receptors present in the body is called stimulus.

Question 2.
Name the parts of the hindbrain.
Answer:
The hindbrain is formed of three parts. Cerebellum, Pons and Medulla Oblongata.

Question 3.
What are the structures involved in the protection of brain?
Answer:
Cranium (skull) and three connective tissue membrane meninges – Duramater, Arachnoid membrane and piamater protect the brain.

Question 4.
Give an example for conditioned reflexes.
Answer:
The conditioned reflexes are the result of practice and learning. Playing the harmonium by striking a particular key, on seeing a music note is an example of conditioned reflexes.

Question 5.
Which acts as a link between the nervous system and endocrine system?
Answer:
Hypothalamus is the link between nervous system and endocrine system as it controls the secretion of hormones from anterior pituitary gland.

Question 6.
Define reflex arc.
Answer:
The path taken by nerve impulse to accomplish reflex action is called a Reflex arc.

VII. Differentiate between:

Question 1.
Voluntary and involuntary actions.
Answer:

Question 2.
Medullated and non-medullated nerve fibre.
Answer:

VIII. Long Answer Questions:

Question 1.
Illustrate the structure and functions of brain.
Answer:
The human brain is divided into 3 major parts. Fore brain, Mid brain and Hind brain.
Fore brian consists of Cerebrum, Thalamus and Hypothalamus.

Mid brain
Parts of the brain is Corpora quadrigemina
Function is control visual and auditory reflexes.

Hind brain consists of Pons, Cerebellum and Medulla Oblongata.

Question 2.
What will you do if someone pricks your hand with a needle? Elucidate the pathway of response with a neat labelled diagram.
Answer:
If we touch a sharp pointed object, we immediately withdraw our hand.
Here the skin is the receptor and it receives the stimulus, that is the pain. This stimulus (pain) in turn triggers an impulse in sensory neuron. The sensory neuron transmits or convey the message to the spinal cord. Spinal cord interprets the stimulus and the impulse is passed on to the relay neuron which in turn transmits it to a motor neuron. Motor neuron carry command from the spinal cord to our arm. Muscle in our arm contracts and we withdraw our hand immediately

Question 3.
With a neat labelled diagram explain the structure of a neuron.
Answer:

A neuron is the basic structural and functional unit of the nervous system. A neuron consists of Cyton, Dendrites and Axon.
Cyton : It has a central nucleus with abundant cytoplasm called neuroplasm. The cytoplasm has large granular body called Nissl’s granules and the other cell organelles like mitochondria, ribosomes, lysosomes, and endoplasmic recticulum.

Dendrites : These are the numerous branched cytoplasmic processes that project from the surface of the cell body. They conduct nerve impulses towards the cyton.

Axon : The axon is a single, elongated, slender projection. The end of axon terminates as fine branches which terminate into knob like swellings called synaptic knob. The plasma membrane of axon is called axolemma, while the cytoplasm is called axoplasm. It carries impulses away from the cyton. The axons may be covered by a protective sheath called myelin sheath which is further covered by a layer of Schwann ceils called neurilemma. Myelin sheath breaks at intervals by depressions called Nodes of Ranvier. The region between the nodes is called as internode. Myelin sheath acts as insulator and ensures rapid transmission of nerve impulses.

Question 4.
Describe the structure of spinal cord.
Answer:
Spinal cord is a cylindrical structure lying in the neural canal of the vertebral column. It is also covered by meninges.
It extends from the lower end of medulla oblongata to the first lumbar vertebra. The posterior most region of spinal cord tapers into a thin fibrous thread like structure called filum terminale.

Internally, the spinal cord contains a cerebrospinal fluid filled cavity known as the central canal. The grey matter of spinal cord is ‘H’ shaped. The upper end of letter ‘H” forms posterior horns and lower end forms anterior horns. A bundle of fibres pass into the posterior horn forming dorsal or afferent root. Fibres pass outward from the anterior hom forming ventral or efferent root. These two roots joins to form spinal nerves. The white matter is external and have bundle of nerve tracts. Spinal cord conducts sensory and motor impulses to and from the brain. It controls reflex actions of the body.

Question 5.
How nerve impulses are transferred from one neuron to next neuron?
Answer:
The information from the environment are detected by the receptors located in our sense organs such as the eyes, the nose, the skin etc..
Information from the receptors is transmitted as electrical impulse and is received by the dendritic tips of the neuron.
This impulse travels from the dendrite to the cell body and then along the axon to its terminal end.

On reaching the axonal end, it causes the nerve endings to release a chemical (neuro transmitter) which diffuses across a synapse and starts a similar electrical impulse in the dendrites of the next neuron, then to their cell body to be carried along the axon.

In this way, the electrical signal reaches the brain or spinal cord. The response from brain (or spinal cord) is similarly passed on to the effector organs such as the muscle or gland cell, that undergoes the desired response.

The flow of nerve impulses from axonal end of one neuron to dendrite of another neuron through a synapse is called synaptic transmission.

Question 6.
Classify neurons based on its structure.
Answer:
The neurons may be of different types based on their structure and functions. Structurally the neurons may be of the following types:

(i) Unipolar neurons: Only one nerve process arises from the cyton which acts as both axon and dendron.
(ii) Bipolar neurons: The cyton gives rise to two nerve processes of which one acts as an axon while another as a dendron.
(iii) Multipolar neurons: The cyton gives rise to many dendrons and an axon.

IX. Higher Order Thinking Skills: (HOTS)

Question 1.
‘A’ is a cylindrical structure that begins from the lower end of the medulla and extends downwards. It is enclosed in bony cage 4B’ and covered by membranes ‘C’. As many as ‘D’ pairs of nerves arise from the structure ‘A’.
(i) What is A?
(ii) Name (a) bony cage ‘B’ and (b) membranes ‘C’
(iii) How much is D?
Answer:
(i) Spinal cord
(ii) (a) Cranium
(b) Duramater, Arachnoid membrane, Piamater
(iii) 31 pairs of Spinal nerves

Question 2.
Our body contains a large number of cells ‘L’ which are the longest cells in the body.
L has long and short branch called as ‘M’ and ‘N’ respectively. There is a gap ‘O’ between two ‘l’ cells, through which nerve impulse transfer by release of chemical substance ‘P’.

1. Name the cells L.
2. what are M and N?
3. What is the gap O?
4. Name the chemical substance P.

Answer:

1. L is Nerve cell or Neuron
2. M is axon and N is dendrite
3. Gap O is synaptic junction
4. P is neuro transmitter – Acetylcholine

Samacheer Kalvi 10th Science Nervous System Additional Important Questions and Answers

I. Choose the correct answer:

Question 1.
Inner layer of Axon is:
(a) Myelin sheath
(b) Neurilemma
(c) Meninges
(d) Sarcolemma
Answer:
(b) Neurilemma

Question 2.
Which one is thin and vascularised?
(a) Piamater
(b) Duramater
(c) Arachnoid membrane
(d) Pleural membrane
Answer:
(b) Duramater

Question 3.
Uni polar neurons are found in:
(a) Adult nervous tissue
(b) Stem cells
(c) Embryonic stem cells
(d) Embryonic nervous tissue
Answer:
(d) Embryonic nervous tissue

Question 4.
Among the following which one controls our anger.
(a) Hypothalamus
(b) Cerebrum
(c) Cerebellum
(d) Thalamus
Answer:
(a) Hypothalamus

Question 5.
………. form the cerebral cortex of our brain.
(a) Grey neuron
(b) Fibrous tissue
(c) White neurons
(d) Ganglions
Answer:
(c) White neurons

Question 6.
……… is fitted with neuro transmitter.
(a) Synaptic knob
(b) Synaptic plate
(c) Synaptic cleft
(d) Synaptic branch
Answer:
(a) Synaptic knob

Question 7.
The functional connection between two neurons is called:
(a) Synapse
(b) Synapsis
(c) Chiasma
(d) Chiasmata
Answer:
(a) Synapse

Question 8.
Which of the following pair is correct?
(a) Sensory nerve – afferent
(b) Motor nerve – afferent
(c) Sensory nerve – ventral
(d) Motor nerve-dorsal
Answer:
(a) Sensory nerve – afferent

Question 9.
A healthy person got injured resulting in damage and death of a few cells. Which of the cells are least likely to be replaced by new cells:
(a) Liver cell
(b) Neuron
(c) Nephron
(d) Osteocytes
Answer:
(b) Neuron

Question 10.
The number of pairs of spinal nerves in human being is:
(a) 12
(b) 18
(c) 31
(d) 24
Answer:
(c) 31

II. Fill in the blanks:

1. ………lies at the base of the thalamus.
2. ………. transmit electrical impulses towards the cyton.
3. The sensory organs contain ………. neuron.
4. Mid brain with ………. together form the brain stems.
5. Chemical substances which take part in synaptic transmission is ……….
6. The membrane which cover the brain and the spinal cord is ………..
7. If the corpus collosum is removed in Mammalian brain then ……… will be affected.
8. Last end of spinal cord is called ………..
9. The …………. is the continuation of medulla oblongata.
10. ………. is the part of the brain which helps to maintain balance.
Answer:
1. Hypothalamus
2. Dendrites
3. Bypolar
4. Hind brain
5. acetycholine
6. Meninges
7. coordination of cerebrum
8. filum terminate
9. spinal cord
10. Cerebellum

III. State whether true or false, if false write the correct statement.

1. The gaps on the cyton are called Nodes of Ranvier.
2. Corpus callosum is a sheet of Nervous tissue that unites the right and left Cerebral Hemisphere.
3. Cerebral aqueduct is found in Mid brain.
4. Dendrites transmit chemical impulse towards the cyton.
5. The lower end of medulla oblongata is filum terminate.

Answer:

1. False – The gaps on the axon are called Nodes of Ranvier.
2. True
3. False – Cerebral aqueduct is found in fore brain.
4. False – Dendrites transmit electrical impulse towards the cyton.
5. True

IV. Match the following:

Answer:
A. (ii)
B. (iv)
C. (i)
D. (v)
E. (iii)

V. Understand the assertion statement.Justify the reason given and choose the correct choice:

(a) Assertion is correct and reason is wrong.
(b) Reason is correct and the assertion is wrong.
(c) Both assertion and reason are correct.
(d) Both assertion and reason are wrong.
1. Assertion: Medulla oblongata is very important for our body.
Reason: Medulla oblongata regulates all in voluntary activities.
Answer:
(c) Both assertion and reason are correct.

2. Assertion: With drawl reflex is controlled by spinal cord.
Reason: Initially cerebrum is involved and require alertness for perform this reflex.
Answer:
(a) Assertion is correct and reason is wrong.

3. Assertion: In human being, cerebrum is most developed part of brain. Reason: Cerebrum is having large surface area and analyzing centre for maintaining body activity.
Answer:
(c) Both assertion and reason are correct.

VI Answer in one or two Sentences.

Question 1.
List the components of Nervous system.
Answer:
The components of Nervous system are brain, spinal cord and brain.

Question 2.
What is Motor or efferent neuron?
Answer:
Motor or efferent neuron carries impulses from the Central Nervous System to effector organs such as muscle fibre or gland.

Question 3.
What is synapse?
Answer:
The paint of contract between the neighbouring nerve cells is called synapse.

Question 4.
Name the outermost fibrous membrane of the brain.
Answer:
Dura mater.

Question 5.
Name the two components, ANS (Autonomic Nervous System).
Answer:
The two antagonistic components of ANS are sympathetic and para sympathetic system.

VII. Short answer questions:

Question 1.
What is Coordination?
Answer:
The various organs working in a systematic controlled and efficient way to produce proper response to various stimuli is called coordination.

Question 2.
What are simple or basic reflexes? Give a few actions, as examples.
Answer:
These simple reflexes are inbuilt and unlearned responses. Many of the actions we perform in our day to day life are simple reflexes, eg. Winking of eyes, Sneezing, Coughing and Yawning. We perform these actions without thinking.

Question 3.
Name the second largest part of the brain. What is its functions?
Answer:
The cerebellum is the second largest part of the brain, formed of two large-sized hemispheres and middle vermis. Maintenance of posture and balance, co-ordinate voluntary muscle activity, are some of the functions of the cerebellum.

Question 4.
Differentiate simple reflexes and conditioned reflexes.
Answer:

VIII. Higher Order Thinking Skills: (HOTS).

Question 1.
Give two examples of conditional reflexion.
Answer:

• Applying the brake while driving, when a red or yellow traffic light appears. We do not have to think about pressing the brake.
• Producing saliva is a response of a dog naturally have, when they smell or see food or when a bell sound was followed by food.

Question 2.
Injury to medulla oblongata can cause death. Why?
Answer:
Medulla Oblongata emerges from the base of the brain and joins the brain to the spinal cord. It controls the involuntary functions.

IX. Long Answer Question:

Question 1.
Classify peripheral nervous based on the nerves arising from the brain and the spinal cord.
Answer:
Peripheral nervous system is formed by the nerves arising from the brain and the spinal cord. The nerves arising from the brain are called cranial nerves. Nerves arising from spinal cord are called spinal nerves.

Cranial Nerves : In man, there are 12 pairs of cranial nerves. Some of the cranial nerves are sensory Eg: optic nerve which innervates the eye. Some are motor nerves which helps in rotation of eyeball. It also innervates the eye muscles, muscles of iris and tear gland.

Spinal Nerves : There are 31 pairs of spinal nerves. Each spinal nerve has a dorsal sensory root and the ventral motor root. The direction of impulses in dorsal spinal root is towards the spinal cord and in ventral spinal root away from the spinal cord.

Question 2.
List out the components of Nervous system and its function.
Answer:
The nervous system is formed of three distinct components namely the neurons, neuroglia and nerve fibres.
(i) Neuron or nerve cell : A neuron or nerve cell is the structural and functional unit of the nervous system. It is the longest cell of the human body with a length of over 100μm. These cells are highly specialised to detect, receive and transmit different kinds of stimuli. Information is conducted through neurons in the form of electrical impulses from one part of the body to another.

(ii) Neuroglia : Neuroglia are also called as glial cells. They are non¬exciting, supporting cell of the nervous system. They do not initiate or conduct nerve impulses.

(iii) Nerve fibres : The nerve fibres are the long slender processes of neurons. A number of nerve fibres are bundled up together to form nerves.

Question 3.
Explain Autonomic Nervous system.
Answer:
Autonomic Nervous System (ANS) is also called as visceral nervous system as it regulates the function of internal visceral organs of our body through its two antagonistic (opposite) components sympathetic and parasympathetic systems. They enable the body to perform rapid and specific visceral activities in order to maintain steady state. It controls the involuntary functions of the visceral organs.

Students can download 10th Social Science Geography Chapter 5 India: Population, Transport, Communication, and Trade Questions and Answers, Notes, Samacheer Kalvi 10th Social Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Social Science Solutions Geography Chapter 5 India: Population, Transport, Communication, and Trade

Samacheer Kalvi 10th Social Science India: Population, Transport, Communication, and Trade Text Book Back Questions and Answers

I. Choose the correct answer

Question 1.
The scientific study of different aspects of population is called:
(a) Photography
(b) Demography
(c) Choreography
(d) Population density
Answer:
(b) Demography

Question 2.
The state with highest literacy rate as per 2011 census is ……..
(a) Tamil nadu
(b) Karnataka
(c) Kerala
(d) Uttarpradesh
Answer:
(c) Kerala

Question 3.
Human Development is measured in terms of:
(a) Human Resource Index
(b) Per capita index
(c) Human Development Index
(d) UNDP
Answer:
(c) Human Development Index

Question 4.
……… Transport provides door to door services.
(a) Railways
(b) Roadways
(c) Airways
(d) Waterways
Answer:
(b) Roadways

Question 5.
The length of Golden Quadrilateral superhighways in India is:
(a) 5846 km
(b) 5847 km
(c) 5849 km
(d) 5800 km
Answer:
(a) 5846 km

Question 6.
The length of navigable Inland waterways in India is ……..
(a) 17,500 km
(b) 5000 km
(c) 14,500 km
(d) 1000 km
Answer:
(c) 14,500 km

Question 7.
The National Remote sensing Centre(NRSC) is located at:
(a) Bengaluru
(b) Chennai
(c) Delhi
(d) Hyderabad
Answer:
(d) Hyderabad

Question 8.
The transport useful in the inaccessible areas is ……..
(a) Roadways
(b) Railways
(c) Airways
(d) Waterways
Answer:
(c) Airways

Question 9.
Which of the following is associated with helicopter service?
(a) Air India
(b) Indian Airlines
(c) Vayudoot
(d) Pavan Hans
Answer:
(d) Pavan Hans

Question 10.
The major import item of India is
(a) Cement
(b) Jewells
(c) Tea
(d) Petroleum
Answer:
(d) Petroleum

II. Match the following

Question 1.
Match the Column I with Column II.


Answer:
A. (v)
B. (i)
C. (iv)
D. (ii)
E. (iii)

III. Answer the following questions briefly

Question 1.
What is Human Development?
Answer:
It is a process of enlarging the range of people’s choice, increasing their opportunities for education, health care, income and empowerment. It covers a full range of human choices from a sound physical environment to economic, social and political freedom.

Question 2.
What is migration? State its types.
Answer:
Migration is the movement of people across regions and territories. It can be internal (within a country) or international (between the countries). Migration depends on

Push factor: Unemployment and underemployment in rural areas.

Pull factor: higher wages, employment opportunity, industrial development.

Question 3.
Write any four advantages of railways.
Answer:

1. Railways are the price mode of transport for goods and passengers in India.
2. They make it possible to conduct varied activities like business, sightseeing and pilgrimage along with transportation of goods over longer distances.
3. They are suitable for long-distance travel and play an important role in national integration.
4. They bind the economic life of the country as well as the accelerate the development of the industry and agriculture.

Question 4.
Write a note on Pipeline network transport in India.
Answer:
Pipelines are the very convenient transport to connect oil and natural gas fields, refineries and to the markets.
It can be laid through difficult Terrain as well as under water.
It ensures steady supply of goods and reduces the transhipment loss and delays.

Three important network of pipeline:

1. Oil fields in upper Assam and Kanpur.
2. From Salaya in Gujarat to Jalandhar in Punjab.
3. From Hazira in Gujarat to Jagadispur in Uttar Pradesh

Question 5.
State the major Inland waterways of India.
Answer:
The major inland waters ways of India are :

1. National Waterway I: It extends between Haldia and Allahabad, measures 1620 km and includes the stretches of the Ganga – Bhagirathi – Hooghly river system.
2. National Waterway 2: This waterway includes the stretch of the Brahmaputra river between Dhubri and Sadiya a distance of 891 km.
3. National Waterway 3: This waterway extends between Kollam and Kottappuram in the state of Kerala. It is the first national waterway in the country with 24 hour navigation facilities along its entire stretch of 205 km.

Question 6.
What is communication? What are its types?
Answer:
Communication is a process that involves exchange of information, thoughts , and ideas. lt is categorized into two types.

Personal Communication: Post and telegraph, telephone, mobile phone, short message services, fax, internet, e-mail etc.
Mass Communication: Electronic media-Radio, T.V, internet and print media-News papers.

Question 7.
Define “International trade”.
Answer:
When trade takes place between two countries it is known as international trade.

Question 8.
State the merits of Roadways.
Answer:

1. Roadways can provide door to door services.
2. Easy and cheap to construct and maintain. Indian roads are cost-efficient.
3. The most universal mode of transport. It is used by all sections of people in society.
4. Can establish easy contact between farms, fields, factories and markets.

IV. Distinguish between

Question 1.
Density of population and Growth of population.
Answer:
Density of Population:

1. Density of population is the number of persons living per square kilometre.
2. It is calculated per 1000.
3. As per 2011 census the average density of population in India is 382 persons living in per sq.km.

Growth of Population:

1. Growth of population refers to the change in the number of in habitants of a country/territory in a specific period of time.
2. It is expressed in percentage.
3. The year 1921 is called the year of Great Demographic Divide.

Question 2.
Persona! communication and Mass communication.
Answer:
Personal communication:

1. Exchange of communication between the individuals.
2. Enables the user to establish direct contact.
3. It includes post and telegraph, telephones, mobile phones, short message service (SMS) fax, Internet, e-mail etc.

Mass communication:

1. Millions of people get the information at the same time.
2. Provide information through print media and electronic media.
3. It includes Radio, Television and Internet. Electronic media, News paper, Magazines, books, journals etc.

Question 3.
Print Media and Electronic Media.
Answer:
Print Media:

1. Most powerful means of communication.
2. Many news papers carry information on local national and international events to the people.
3. Knowledge of reading is essential.

Electronic Media:

1. Communication to millions of people through electronic gadgets at the same time.
2. Radio, Television, Internet provide and create awareness on various national policies and programme.
3. A powerful audio-visual medium.

Question 4.
Roadways and Railways.
Answer:
Roadways:

1. Highly suitable for short distance services.
2. Most common mode of transport, easy, cheap to construct and maintain.
3. Based on the construction and maintenance divided into National Highways, State Highways, District Roads, Village roads, Border roads, International highways, Express ways.
4. Second longest network in the world.
5. Door to door services possible

Railways:

1. Ideal for long distance services.
2. Construction depend upon the climatic and physical factors like terrain. Costly when compared with roadways.
3. On the basis of width of the track falls under 4 types, Broad gauge, meter gauge, narrow gauge and light gauge.
4. Largest in Asia and second largest in the World.
5. Cannot provide door to door services.

Question 5.
Waterways and Airways.
Answer:
Waterways:

1. Oldest and Cheapest means of transport.
2. Most suitable for carrying heavy and bulky materials.
3. Two types, inland waterways-river and backwaters and canals and oceanic routes connect coastal areas.

Airways:

1. Modem and costliest means of transport.
2. Only limited weight can be carried. Cannot carry heavy and bulky materials.
3. Domestic air sendee within the country and International Airways connect major cities of the World.

Question 6.
internal trade and International trade.
Answer:
Internal trade:

1. Trade is carried on within the domestic territory.
2. Land transport plays a major role (Roadways and Railways).
3. Local currency is used.
4. Helps to promote a balanced regional growth.

International trade:

1. Trade is carried on between two or more countries.
2. Waterways and Airways play a vital role.
3. Foreign currency is involved.
4. Helps to promote country’s economy and raise the standard of living

V. Answer the following in a paragraph

Question 1.
What is urbanization? Explain its impacts.
Answer:
The process of society’s transformation from rural to urban is known as urbanization. The level of urbanization of a place is assessed based on the size of population of the towns and cities and the proportion of population engaged in non agricultural sectors. These two are closely linked to the process of industrialization and expansion of the secondary and tertiary sectors of economy.
Impacts of urbanization:

• Urbanization and population concentration go hand – in – hand and are closely related to each other. A rapid rate of urbanization in a society is taken as an indicator of its economic development.
• Urbanization is increasing rapidly in the developing countries including India.
• Rural to urban migration leads to population explosion in urban areas. Metropolitan cities like Mumbai, Kolkatta and Delhi have more population than that can accommodate.
  The following are the major problem of urbanization in India.
• It creates urban sprawl.
• It makes overcrowding in urban centres.
• It leads to shortage of houses in urban areas.
• It leads to the formation of slums.
• It increases traffic congestion in cities.
• It creates water scarcity in cities.
• It creates drainage problems.
• It poses the problem of solid waste management.
• It increases the rate of crime.

Question 2.
Explain the importances of satellite communication in India.
Answer:

1. The communication through satellites emerged as a new era in the system of communication in our country.
2. The use of Satellite in getting a continuous and synoptic view of larger area has made this communication system very vital for the country.
3. Satellite images are used for weather forecasting.
4. Monitoring of natural calamities.
5. Surveillance of border areas.
6. The INSAT (series) is a multipurpose system for telecommunication, meterological observation and for various other programs.
7. They are used for relaying signals to television, telephone, radio and mobile phone.
8. And also useful in weather detection, internet and military applications.

Question 3.
Bring out the distribution and density of population in India.
Answer:
The term ‘Population Distribution’ refers to the way the people are spaced over the earth’s surface. The distribution of population in India is quite uneven because of the vast variation ki the availability of resources. The population is mostly concentrated in the regions of industrial centres and the good agricultural lands. On the other hand, the areas such as high mountains and lands thickly forested areas and some remote comers are very thinly populated and some areas are even uninhabited.

Terrain, climate, soil, water bodies, mineral resources, industries, transport and urbanization are the major factors which affect the distribution of population in our country. Population density is a better measure of understanding the variation in distribution of population. It is expressed as number of person per unit area usually per sq.km. According to 2011, the average density of population of India is 382 person per sq.km. India is one of the most thickly populated ten countries of the world. The most densely populated state of India is Bihar and the state with lest population density is Arunachal Pradesh. Among union territories, Delhi is the densely populated one with 11,297 per sq.km, while Andaman and Nicobar Islands have the lowest density of population.

Question 4.
Explain the process of measuring Human Development.
Answer:
Dr. Mahabub-ul-haq defined Human Development as “It is a process of enlarging the range of people’s choice, increasing their opportunities for education, health care, income and empowerment. It covers the full range of human choices from a. sound physical environment to economic, social and political freedom”.

Measuring of Human Development (HDI): Human Development Index is a composite index focusing on three basic dimensions of human development.

1. Health: Life expectancy at birth.
2. Education: Expected years of schooling for school age children and average years of schooling for the adult population.
3. Income: Measured by gross national income and per capita income.

Question 5.
Classify and explain the roadways in India.
Answer:

1. The Indian roads are cost-efficient and the most popular dominant mode of transport
   linking different parts of our country.
2. Roads stretch across the length of people in society.
3. It is used by all sections of people in society.
4. Road network in India is the second-longest in the world accounting for 3,314 millions of km.

Types of Roadways:

1. Village Roads:

• Village roads link different villages with towns.
• They are maintained by Village Panchayath.
• In India village roads run to a length of 26,50,000 kms.

2. District Roads:

• District roads link the towns with the district headquarters.
• They are maintained by the Corporations and Municipalities.
• It is used by all sections of people in the society.
• In India district roads run to a total length of 4,67,763 kms.

3. State Highways:

• State Highways links the State capitals with the different district headquarters.
• These roads are maintained by the State Public Works Department.
• The State Highways run to a length of 1,31,899 kms. (Ex: Cudalore – Chittor Road).

4. National Highways:

• National Highways link the State Capitals with the National Capital.
• They are the primary road system of our country and are maintained by the Central Public Works Department.
• It runs to a length of 70,548 kms. (Ex: NH47 is a National Highway which connects Tamil Nadu and Kerala)

5. Golden Quadrilateral Super Highways:

• It is a major road development project launched by the Government of India.
• It runs to a length of 14,846 kms connecting the major cities of India.
• The major objective of these roads is providing ‘connectivity’, ‘speed’ and ‘safety’.

6. Expressways:

• Expressways are the technologically improved high class roads in the Indian Road network.
• They are six lanes roads. They run to a length of more than 200 kms.
• New Mumbai – Pune Road is an example for Expressway.

7. Border Road:

• Border Roads are the roads constructed along the northern and north eastern borders of our country.
• These roads are constructed and maintained by Border Roads Organization.
• The Organization has constructed 46,780 km of roads in difficult terrain.

8. International Highways:
International Highways are the roads that link India with neighbouring countries for promoting harmonious relationship with them.

VI. On the outline map of India mark the following

Question 1.
National Highway NH-7.
Answer:

Question 2.
Major seaports in India.
Answer:

Question 3.
Major International Airports in India.
Answer:

Question 4.
Densely populated state of India – Uttarpradesh
Answer:

Question 5.
State of highest literacy in India – Kerala
Answer:

Question 6.
Railways zones of India.
Answer:

TB Page No. 151
Hots:

Question 1.
What could be the reasons for uneven distribution of population in India?
Answer:

• Topography, favourable climate, fertility of soils, availability of fresh water, minerals are major geographical factors affecting population density of a region.
• People prefer to live on plains more than mountains or plateaus and they live more in moderate climates than extreme hot or cold. From the agriculture point of view, fertile lands are preferred.
• Areas with mineral deposits are more populated.
• Some social factors that boost the density of population in a region are better housing, education and health facilities.
• Places with cultural or historical significances are usually populated.
• Employment opportunities is another attraction for large chunks of the population.

Question 2.
What are the reasons for the rapid growth of population in India?
Answer:

1. The reasons for the rapid growth of population in India is mainly the , high birth rate and low death rate.
2. Birth rate is high, death rate declined due to advanced medical facilities and immunization to dreadful diseases.
3. And also migration of population due to employment, education and industrial development.

TB Page No. 154

Question 3.
The sex ratio in our country is always unfavourable to females. Give reasons.
Answer:
The number of females per thousand men is called the sex ratio.
Reasons:

• Lesser care of female children.
• Greater risk to womens’ life especially at the time of child brith.
• Women are also killed or forced to die by the dowry seekers.
• Due to illiteracy.
• Lack of medical facilities for women, etc.

TB Page No. 158

Question 4.
Find out what are the functions of NHAI?
Answer:

1. National Highway Authority of India was established in 1995.
2. It is an autonomous body under the ministry of Surface Transport.
3. Management of all major National Highways and the highways entrusted to it.
4. Maintenance, development and operation of the National Highways is undertaken by NHAI.

Question 5.
What are the highlights and benefits of the Golden Quadrilateral Highways? Highlights:
Answer:

• It is the largest Highway project completed in India.
• It is the fifth largest highway project in the world.
• The overall length of the Golden Quadrilateral is 5,846 km.
• The Golden Quadrilateral passes through 13 states of India.
• It connects four major metropolitan cities of the country in four directions.

Benefits:

• Provides faster transport networks between major cities and ports.
• Provides connectivity to major agricultural industrial and cultural centres of India.
• Provides smoother movement of goods and people within the country.
• Enables industrial development and job creation in smaller town through access to varied markets.
• Farmers are able to transport their produce to major cities and towns for sale and export and there is less wastage and spoils.
• More economic growth through construction and indirect demand for steel, cement, and other construction materials.
• Giving an impetus to truck transports.

TB Page No. 162

Question 6.
Why is air travel preferred in the North Eastern State?
Answer:
The North Eastern States are mountainous and forested. So construction of roadways or railways is very difficult due to terrains. Air transport has made accessibility easier. So air travel is preferred in the North eastern states.

TB Page No. 165

Question 7.
Find out the major trade blocs which are useful for multilateral trade.
Answer:
Trading blocs are usually groups of countries in specific regions that manage and promote trade activities. Trading blocs lead to trade liberalisation and trade creation between members, since they are treated favourably in comparison to non-members. The World Trade Organisation (WTO) permits the existence of trading bloc provided that they result in lower protection against outside countries than existed before the creation trading bloc.
The most significant trading blocs currently are:

1. European Union (EU): A customs union, a single market and now with a single currency.
2. European Free Trade Area (EFTA)
3. North American Free Trade Agreement (NFATA) between the USA, Canada and Mexico.
4. Mercosur: A customs union between Argentina, Brazil, Paraguay, Uruguay, and Venezuela.
5. Association of Southeast Asian Nations (ASEAN)
6. Association of Free Trade Area (AFTA)
7. Common market of Eastern and Southern Africa (COMESA)
8. South Asian Free Trade Area (SAFTA) created in 2006 with countries such as India and Pakistan.
9. Pacific Alliance: 2013 – a regional trade agreement between Chile, Colombia, Mexico and Peru.

TB Page No. 159
Activity:

Question 1.
Prepare a seminar topic about “Role of Railways in Indian Economy”Key Points:
Answer:

1. Large scale movement
2. National integration promotion
3. Commercialisation of agriculture
4. Movement of perishable goods
5. Avoids traffic congestion how?
6. Engineering marvel
7. Quiz regarding railways

TB Page No. 165

Question 2.
Collect the countries names and make it as a table of Bilateral trade and multilateral trade countries.
Answer:
India has made bilateral trade agreement with these countries.

Bilateral Trade Countries: U.S.A . China, Hongkong, Singapore, United Kingdom, Germany, Bangladesh.

Multilateral Trade Countries: The members of the SAARC (South Asian Association for Regional Cooperation) Korea, Japan, Bangladesh, Bhutan, Maldives, Nepal, Pakistan, Afghanistan, Srilanka, U.S.A and United Kingdom.

Samacheer Kalvi 10th Social Science India: Population, Transport, Communication, and Trade Additional Important Questions and Answers

I. Choose the correct answer

Question 1.
…………………. is the second-most populous country next to China.
(a) India
(b) Pakistan
(c) Bangladesh
(d) Nepal
Answer:
(a) India

Question 2.
The fast movement of traffic are established by ……
(a) national highways
(b) Express highways
(c) International highways
Answer:
(a) national highways

Question 3.
As per 2011 census the average density of population of India is …………………. persons per Sq.Km.
(a) 302
(b) 382
(c) 100
(d) 365
Answer:
(b) 382

Question 4.
The ………. have more railways than the Himalayan Mountains.
(a) Northern Plains
(b) Coastal Plains
(c) Deccan Plateau
Answer:
(a) Northern Plains

Question 5.
The Grand Trunk Road extends from …………………. to ………………….
(a) Delhi to Mumbai
(b) Amritsar to Kolkatta
(c) Mumbai to Thane
(d) Srinagar to Amritsar.
Answer:
(b) Amritsar to Kolkatta

Question 6.
The cheapest mode of transport is …….
(a) roadways
(b) railways
(c) waterways
Answer:
(c) waterways

Question 7.
…………………. are multi-lane good quality highways for high speed traffic.
(a) National Highways
(b) State highways
(c) Border roads
(d) Express highways.
Answer:
(d) Express highways.

Question 8.
Trade carried on within the domestic territory of a country is known as …… trade.
(a) External
(b) Foreign
(c) Internal
Answer:
(c) Internal

Question 9.
The …………………. railway accounts for the longest route length.
(a) Northern Railways
(b) Central Railway
(c) Eastern railway
(d) Southern Railway
Answer:
(a) Northern Railways

Question 10.
A cost-efficient and most popular mode of transport in our country is ……..
(a) Airways
(b) Roadways
(c) Waterways
Answer:
(b) Roadways

Question 11.
India is the …………………. largest ship owning country in Asia.
(a) First
(b) Second
(c) Third
(d) Fourth
Answer:
(b) Second

Question 12.
The costliest and most modem means of transport is ……..
(a) Air transport
(b) Road transport
(c) Rail transport
Answer:
(a) Air transport

Question 13.
The is the first communication Satellite in INSAT Series.
(a) G.SAT
(b) EDUSAT
(c) INSAT-IB
(d) Kalpana-1
Answer:
(c) INSAT-IB

Question 14.
The major ports are managed and controlled by …….
(a) National Ports Corporation
(b) Port Trust of India
(c) Indian Airlines
Answer:
(b) Port Trust of India

Question 15.
Indian space Research organisation was established in the year:
(a) 1959
(b) 1969
(c) 1979
(d) 1996
Answer:
(b) 1969

II. Match the following

Question 1.
Match the Column I with Column II.


Answer:
A. (v)
B. (iv)
C. (i)
D. (iii)
E. (ii)

Question 2.
Match the Column I with Column II.

Answer:
A. (iii)
B. (iv)
C. (v)
D. (i)
E. (ii)

III. Answer the following questions briefly

Question 1.
Describe the three population density zones of India.
Answer:
The three population density zones of India are :

1. High-density zone: The Northern plains above 500 people per sq.km. Northern plains and Kerala in the. South.
2. Moderate or Medium density zone: Mountain region 250-500 people per sq.km. Ex. Assam and Peninsular states.
3. Low-density zone: Plateau region below 250 people per sq.km. Ex. Jammu and Kashmir, Sikkim, Arunachal Pradesh.

Question 2.
What are the reasons for the uneven distribution of population in India?
Answer:
The uneven distribution of population in the country is the result of several factors such as physical, socio-economic and historical factors.

Physical factors: Relief, climate, water, natural vegetation, minerals and energy resources.

Socio-economic factors: Religion, culture, political issues, economy, human settlements, transport network, industrialization, urbanization, employment opportunity etc.

Question 3.
What is the major objective to develop the Super Highways?
Answer:
The major objective to develop the Super Highways is to reduce the time and distance between
the megacities of India facilitating the fast movement of traffic.

Question 4.
Which phase period in population growth of India is often referred as period of population explosion?
Answer:
During the third phase (1951-1981) the population of India grew from 361 million in 1951 to 683 million in 1981. Growth rate in this period is almost doubled. So this period (1951-1981) is often referred as the period of “population explosion”.

Question 5.
State some problems of road transport in our country.
Answer:

1. Distribution of road is not uniform in the country.
2. Keeping in view the volume of traffic and passengers, the road network is inadequate.
3. About half of the roads are unmetalled and this restricts their usage during the rainy season.
4. The roadways are highly congested in cities.
5. Poor maintenance is also a big problem.

Question 6.
What are the four major shipyards in India?
Answer:
India as four major shipyards:

1. Hindustan shipyard – Vishakapatnam
2. Garden Reach workshop – Kolkata
3. Mazagaon Dock – Mumbai
4. Kochi shipyard – Kochi

Question 7.
State the highlights of India’s foreign trade policy since 2004.
Answer:

1. Merchandise trade has been doubled.
2. Thrust is given for employment generation; especially in semi-urban and rural areas.
3. Trade procedure is simplified and transaction cost is reduced.
4. Special focus is given to make India a global hub.
5. A new scheme called Vishesh Krishi Upay Yojna has been introduced to boost exports of fruits, vegetables, flowers and minor forest products.

Question 8.
Mention the services provided by the Indian postal system in India.
Answer:
Pcstai system is one among the personal communication system. The postal service was open to the public in the country in 1837.

1. Collecting and delivering mail is the primary function of the postal department.
2. It introduced Quick Mail Service in 1975 on the basis ofPIN code (1972)
3. The premium products include the Money order. E-money order, Speed post. Express parcel post, Business post, Media post, Retail post, Data post, Satellite post, Greeting post, Speed net and Speed passport services,

Question 9.
What are the advantages of communication network?
Answer:

1. It has enhanced the efficiency of communication. Because it enables quick exchange of information with people any where in the world.
2. It leads to enormous growth of trade.
3. It helps the government to tackle various socio – economic problems in the society.
4. It improves the quality of human life.
5. It opens the door to the information age.
6. It promotes Edusat programs.
7. It plays a significant role in the economic and social growth of our country.

Question 10.
Write the full form of STD, ISD, PCO, Internet.
Answer:

• STD – Subscriber Trunk Dialing
• ISD – International Subscriber Dialing
• PCO – Public Call Office
• Internet – Inter connected network.

Question 11.
What are major ports along the West Coast and East Coast?
Answer:
West Coast Ports :

1. Kandla,
2. Mumbai,
3. Jawahar Lal Nehru,
4. Marmagoa,
5. New Mangalore and
6. Cochin East Cost Ports:
   • Tuticorin,
   • Chennai,
   • Ennore,
   • Vishakhapatnam,
   • Paradip,
   • Haldia and
   • Kolkota.

Question 12.
Name the major ports on the East coast and on the West Coast of India.
Answer:
There are 13 major ports in India. They are administered by the Central Government.

1. The major ports on the East coast are Kolkata, Haldia, Paradip,Visakhapatnam, Chennai, Ennore and Tuticorin.
2. The major ports on the West Coast are Kandla, Mumbai, Nhava Seva (Jawaharial Nehru Port), New Mangalore, Marmagao and Kochi.

Question 13.
Write a short note on Internet.
Answer:

1. Internet is a vast network of computers, Internet means interconnected network of net , works.
2. It connects many of the world’s business institutions and individuals.
3. It enables computer users throughout the world to send and receive messages and information in a variety of forms.
4. It is fully a multimedia based system with capacity to deliver pictures, images, video and audio.
5. The basic services of internet are e-mail. The World Wide Web and Internet Phone.

IV. Distinguish between

Question 1.
Exports and Imports.
Exports:

1. Goods and services sold for foreign currency.
2. Major exports of India are tea, ores and minerals, marine products, textiles etc.
3. Value of exports are more than the value of imports favourable balance of trade.
4. India exports goods to nearly 190 countries of the world.

Imports:

1. Goods and services bought from overseas producers.
2. Major imports are petroleum products, gold, telecom instruments.
3. Value of imports exceeds value of exports unfavourable balance of trade.
4. Imports we get from nearly 140 countries.

Question 2.
Low Density and High Density of population.
Answer:
Low Density of Population:

1. Areas that have 150 to 300 persons living per sq.km.
2. Extreme climate, high mountains, remote areas, forested regions have low density of population.
3. In India Arunachal Pradesh, Sikkim, Mizoram, Andaman and Nicobar islands are some states with low population density.

High Density of Population:

1. Areas that have 500 to 1000 persons living per sq.km.
2. Favourable climate, plains, employment opportunities, industrial centres area have high density of population.
3. Punjab, Tamil Nadu, Uttar Pradesh and Kerala are the states with high population density.

Question 3.
National and State Highways.
Answer:
National Highways:

1. Connects Capitals of States, major ports, rail junctions, industrial and tourist centres.
2. Ministry of Road transport and Highways of India is responsible development and maintenance.
3. Runs to a length of 1,01,011 kms as of 2016.

State Highways:

1. Link important cities, towns and district head quarters within the State and connect them with national highways or highways of neighbouring states.
2. Administered and financed by state Governments.
3. Runs to the length of 1,76,166 kms as of 2016.

Question 4.
Domestic and International Airways.
Answer:
Domestic Airways:

1. Fly within the boundaries of the country.
2. Indian Airlines provides the domestic air services. NACIL (I)
3. There are about 80 domestic airports and about 25 civil enclaves at defence air fields.

International Airways:

1. Fly across the world and connect major cities of the world.
2. Air India provides international air services. NACIL (A)
3. There are 19 designated international airports in the country.

Question 5.
Harbour and Port.
Answer:
Harbour:

1. Extensive stretch of deep water near the seashore.
2. Vessels can anchor securely.

Port:

1. Commercial part of a harbour.
2. Facility of loading and unloading of goods and space for the storage of cargo
3. Cuddalore, Ennore.

Question 6.
Birth and Death.
Answer:
Birth Rate:

1. No. of live Births per 1000 people in a year.
2. Also known as Nationality rate.

Death Rate:

1. No. of Deaths per 1000 people in a year.
2. Also known as Mortality rate.

V. Answer the following in a paragraph

Question 1.
What is the importance of railway transport?
Answer:

1. The Indian Railways have been a great integrating force for more than 150 years.
2. They have a network of about 7,112 stations spread over a route length of 66,687 km with a fleet of 11,122 locomotives, 70,241 passenger coaches and 2,54,000 wagons.
3. Railways are the prime mode of transport for goods and passengers in India.
4. They make it possible to conduct varied activities like business, sightseeing and pilgrimage along with transportation of goods over longer distances.
5. They are suitable for long distance travel and play an important role in national integration.
6. They bind the economic life of the country as well as accelerate the development of the industry and agriculture.
7. The Indian Railways is the largest public sector undertaking in the country. The first train streamed of from Mumbai to Thane in 1853, covering a distance of 34 km.

Question 2.
What do you mean by Census? How it is useful?
Answer:

1. Population census is the total process of collecting, compiling, analyzing or otherwise disseminating demographic, economic and social data pertaining at a specific time, of all persons in a country or a well defined part of a country.
2. Census is being taken in an interval of ten years.
3. The data collected through the census are used for administration, planning, policy making, management and evaluation of various programmes by the government.
4. In India 1st census was carried out in the year 1872.
5. But the first complete and synchronous census was conducted in 1881 The 2011 census represents the fifteenth census of India.

Question 3.
Describe the importance of pipelines in India. Name three important networks of pipelines transportation in the country.
Answer:
Pipeline transport network is a new arrival on the transportation of India.

1. Transport of crude oil, petroleum products and natural gas from oil and natural gas fields to refineries, fertiliser factories and big thermal power plants. ‘
2. Even solids can be transported through pipelines when converted into slurry.
3. The far inland locations of refineries and gas based fertiliser plants could be transported.
4. Initial cost of lying pipelines is high but subsequent running costs are tninimal.
5. It rules out trans-shipment losses or delays.

Three important networks of pipeline transportation in the country:

• From oil field in the upper Assam to Kanpur (UP), via Guwahati, Baraumi and Allahabad.
• From Salaya in Gujarat to Jalandhar in Punjab. Via Viramgam, Mathura, Delhi and Sonipat.
• Gas pipeline from Hazira in Gujarat connects Jagdishpur in UP, via Vijaipur in MP.

Question 4.
What are the problems created by over population in India?
Answer:
In India, growing pressure of Population on resource base, created many socio economic, cultural, political, ecological and environmental problems. The population problem varies in space and time and differ from region to region.

Major issues created by the over population are – overcrowding, unemployment and under employment, low standard of living mal nutrition, mismanagement of natural and agricultural resources, unhealthy environment etc.

Question 5.
Write about the significance of Indian Railways.
Answer:

1. Indian Railway system is the main artery of the country’s inland transport.
2. Indian Railway network is the largest in Asia and second largest in the world.
3. Railways are considered as the back bone of the surface transport system of India.
4. Significances: It caters to the needs of large scale movement of traffic both for freight and passengers, there by contributing to economic growth.
5. It promotes trade, tourism, education etc.
6. It promotes national integration by bringing people together.
7. Railways help in the commercialization of the agricultural sector by facilitating the quick movements of perishable goods.
8. It provides invaluable service by transporting raw materials to industries and finished goods to market.

Question 6.
What is trade? What are the two types of trade? State its components:
Answer:

1. Trade is an act (or) process of buying selling or exchanging of goods and services. Trade in general is of two types. They are Internal trade and International trade.
2. Internal Trade: Trade carried on within the domestic territory of a country.
3. International trade: Trade carried on between two or more countries.
4. Exports and imports are the two components of international trade.
5. The difference between value of exports and imports is called balance of trade.
6. If the value of exports exceeds the value of imports trade is said to be favourable balance of trade.
7. If the value of Imports exceeds value of exports it is said to be unfavourable balance of trade.
8. The value of currency of a country depends upon the balance of trade of that country.

VI. On the outline map of India mark the following

Question 1.
North-South corridor
Answer:

Question 2.
East-West corridor
Answer:

Question 3.
Head quarters of Indian Railway – Delhi.
Answer:

Students can download 10th Science Chapter 14 Transportation in Plants and Circulation in Animals Questions and Answers, Notes, Samacheer Kalvi 10th Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 14 Transportation in Plants and Circulation in Animals

Samacheer Kalvi 10th Science Transportation in Plants and Circulation in Animals Text Book Back Questions and Answers

I. Choose the best answer:

Question 1.
Active transport involves:
(a) movement of molecules from lower to higher concentration
(b) expenditure of energy
(c) it is an uphill task
(d) all of the above
Answer:
(d) all of the above

Question 2.
Water which is absorbed by roots is transported to aerial parts of the plant through ______.
(a) cortex
(b) epidermis
(c) phloem
(d) xylem.
Answer:
(d) xylem.

Question 3.
During transpiration there is loss of:
(a) carbon dioxide
(b) oxygen
(c) water
(d) none of the above
Answer:
(c) water

Question 4.
Root hairs are ______.
(a) cortical cell
(b) projection of the epidermal cell
(c) unicellular
(d) both b and c.
Answer:
(b) projection of the epidermal cell

Question 5.
Which of the following process requires energy?
(a) active transport
(b) diffusion
(c) osmosis
(d) all of them
Answer:
(a) active transport

Question 6.
The wall of the human heart is made of ______.
(a) Endocardium
(b) Epicardium
(c) Myocardium
(d) All of the above.
Answer:
(d) All of the above.

Question 7.
Which is the sequence of correct blood flow?
(a) ventricle – atrium – vein – arteries
(b) atrium – ventricle – veins – arteries
(c) atrium – ventricle – arteries – vein
(d) ventricles – vein – atrium – arteries
Answer:
(c) atrium – ventricle – arteries – vein

Question 8.
A patient with blood group O was injured in an accident and has blood loss. Which blood group the doctor should effectively use for transfusion in this condition?
(a) O group
(b) AB group
(c) A or B group
(d) all blood group.
Answer:
(d) all blood group.

Question 9.
‘Heart of heart’ is called:
(a) SA node
(b) AV node
(c) Purkinje fibres
(d) Bundle of His
Answer:
(a) SA node

Question 10.
Which one of the following regarding blood composition is correct?
(a) Plasma – Blood + Lymphocyte
(b) Serum – Blood + Fibrinogen
(c) Lymph – Plasma + RBC + WBC
(d) Blood – Plasma + RBC + WBC + Platelets.
Answer:
(d) Blood – Plasma + RBC+ WBG + Platelets.

II. Fill in the blanks:

1. ……….. involves evaporative loss of water from aerial parts.
2. Water enters the root cell through a ………. plasma membrane.
3. Structures in roots that help to absorb water are …………
4. Normal blood pressure is …………
5. The normal human heartbeat rate is about ……….. time per minute.

Answer:

1. Transpiration
2. Semipermeable
3. Root hairs
4. 120 mm / 80 mm Hg
5. 72 – 75 times

III. Match the following:

Section – I

Answer:
A. (ii)
B. (i)
C. (iv)
D. (iii)

Section – II

Answer:
A. (iv)
B. (i)
C. (ii)
D. (iii)
E. (viii)
F. (vii)
G. (v)
H. (vi)

IV. State whether True or False. If false write the correct statement:

1. The phloem is responsible for the translocation of food.
2. Plants lose water by the process of transpiration.
3. The form of sugar transported through the phloem is glucose.
4. In apoplastic movement the water travels through the cell membrane and enter the cell.
5. When the guard cells lose water the stoma opens.
6. Initiation and stimulation of heart beat take place by nerves.
7. All veins carry deoxygenated blood.
8. WBC defend the body from bacterial and viral infections.
9. The closure of the mitral and tricuspid valves at the start of the ventricular systole produces the first sound ‘LUBB’.

Answer:

1. True
2. True
3. False – The form of sugar transported through the phloem is sucrose.
4. False – Apoplastic movement does not involve crossing the cell membrane.
5. False – When the guard cells lose water the stoma closes.
6. False – Initiation and stimulation of heart beat take place by Sino-atrial node.
7. False – All veins carry deoxygenated blood except the pulmonary veins,
8. True
9. True.

V. Answer in a word or sentence:

Question 1.
Name two layered protective covering of human heart.
Answer:
Pericardium is the two layered protective covering of human heart.

Question 2.
What is the shape of RBC in human blood?
Answer:
The shape of RBC in human blood is biconcave and disc – shaped.

Question 3.
Why is the colour of the blood red?
Answer:
The blood is red in colour due to the presence of respiratory pigment – haemoglobin.

Question 4.
Which kind of cells are found in the lymph?
Answer:
Lymphocytes in the lymph, which defend the body from infection.

Question 5.
Name the heart valve associated with the major arteries leaving the ventricles.
Answer:
Aortic valve present at the base of aorta.

Question 6.
Mention the artery which supplies blood to the heart muscle.
Answer:
Coronary arteries.

VI. Short Answer Questions.

Question 1.
What causes the opening and closing of guard cells of stomata during transpiration?
Answer:
The general mechanism of stomatal movement is based on entry and exit of water molecules in guard cells. When the turgidity increases within the guard cells the stomata open. When the guard cells lose water it becomes flaccid and the stomata closes.

Question 2.
What is cohesion?
Answer:
The force of attraction between molecules of water is called Cohesion.

Question 3.
Trace the pathway followed by water molecules from the time it enters a plant root to the time it escapes into the atmosphere from a leaf.
Answer:
Soil → root hair → cortex → endodermis → Pericycle → xylem → stem → leaves.

Question 4.
What would happen to the leaves of a plant that transpires more water than its absorption in the roots?
Answer:
When transpiration exceeds than water absorption by roots, the plant dehydrates. It affects plant processes such as growth, Photosynthesis and transpiration.

Question 5.
Describe the structure and working of the human heart.
Answer:
The heart is thick muscular organ located in the thoracic cavity. It is covered by a two layered sac called pericardium. The heart is four chambered with two auricles and two ventricles. Right Auricle receives deoxygenated blood from superior and inferior vena cava and passes to right ventricles from right ventricles impure blood passes to pulmonary artery and reaches the lungs.

Question 6.
Why is the circulation in man referred to as double circulation?
Answer:
The blood circulates twice, through the heart in one complete cycle, in the circulation of blood in man. So it is called double circulation.

Question 7.
What are heart sounds? How are they produced?
Answer:
‘Lubb’ and ‘Dupp’ are the sounds of the heart. ‘Lubb’ sound is produced by the ventricle- contraction. It arises due to closing of mitral and tricuspid valve.
‘Dupp’ is produced by ventricular diastole. This arises due to the closing of the semi-lunar valves of two auricles.

Question 8.
What is the importance of valves in the heart?
Answer:
The valves are the muscular flaps, that regulate the flow of blood in a single direction and prevent backflow of blood.

Question 9.
Who discovered Rh factor? Why was it named so?
Answer:
Landsteiner and Wiener discovered Rh factor of blood in 1940. Rh factor is a protein CD antigen present on the surface of the red blood cells in majority of humans. This protein is similar to the protein present in Rhesus monkey, hence the term Rh.

Question 10.
How are arteries and veins structurally different from one another?
Answer:

Question 11.
Why is the Sinoatrial node called the pacemaker of the heart?
Answer:
Sinoatrial node is called the pacemaker of the heart because it is capable of initiating impulse, which can stimulate the heart muscles to contract.

Question 12.
Differentiate between systemic circulation and pulmonary circulation.
Answer:

Question 13.
The complete events of the cardiac cycle last for 0.8 sec. What is the timing for each event?
Answer:

1. Atrial Systole: Contraction of auricles (0.1 sec)
2. Ventricular Systole: Contraction of ventricles (0.3 sec)
3. Ventricular diastole: Relaxation of Ventricles (0.4 sec).

VII. Give reasons for the following statements:

Question 1.
Minerals cannot be passively absorbed by the roots.
Answer:
All minerals cannot be passively absorbed by the roots because, minerals are present in the soil as charged particles that cannot move across the cell membranes and the concentration of minerals in the soil is usually lower than the. concentration of minerals in the root. So, the minerals enter the root by active absorption through the cytoplasm of epidermal cells which needs energy.

Question 2.
Guard cells are responsible for opening and closing of stomata.
Answer:
Guard cells are responsible for the opening and closing of stomata because, during transpiration, the movement of ions (Potassium) in and out of the guard cells causes the opening and closing of Stomata. When the water moves inside the guard cells, causing them to swell up and become turgid making the stomata open. When guard cells cause water to move out of the cell and make guard cells shrunk and stomata pores close.

Question 3.
The movement of substances in the phloem can be in any direction.
Answer:
Phloem transports food from the source to sink. The source is part in which plant synthesize food, sink is the part that needs or stores food. Since the source-sink relationship is variable, the direction of movement in the Phloem can be upwards or downwards, i.e., bidirectional.

Question 4.
Minerals in the plants are not lost when the leaf falls.
Answer:
Minerals like Phosphorus, Sulphur, Nitrogen and Potassium are remobilised in the soil from older dying leaves to younger leaves. This phenomenon is seen in deciduous plants. So minerals in the plants are not lost, when the leaf falls.

Question 5.
The walls of the right ventricle are thicker than the right auricles.
Answer:
Because the right ventricle have to pump out the deoxygenated blood with force away from the heart through pulmonary artery to lungs.

Question 6.
Mature RBC in mammals does not have cell organelles.
Answer:
Mature RBC in mammals does not have cell organelles because

• The lack of Nucleus in RBC makes the cells, biconcave and disc – shaped. RBC involved in the transport of oxygen from lungs to tissues.
• They do not have cell organelles in order to accommodate maximum space for haemoglobin.
• The loss of endoplasmic reticulum allows more flexibility, for RBC to move through narrow capillaries.

VIII. Long Answer Questions:

Question 1.
How do plants absorb water? Explain.
Answer:
Water present in the soil must reach the xylem of roots. Root hair is in contact with soil water. Their cell wall is thin and water easily diffuses in the passage of water from the soil to leaf is
Soil water → Root hair → Epidermis → Cortex → Endodermis → Pericycle → Xylem → Stem and leaf.
Once water is absorbed by the root hairs, it can move deepers into root layers by two pathways. Apoplast and Symplast.

1. Apoplast : This is the non living path in plants. It occurs through the intercellular spaces and walls of the cells. This movement dependent on the gradient.
2. Symplast : This is the living passage. The movement of water from cell to cell through plasmodesmato and cytoplasm, Movement is again down a potential gradient.

Question 2.
What is transpiration? Give the importance of transpiration.
Answer:
Transpiration is the evaporation of water in plants through stomata in the leaves.
Importance of Transpiration

• Creates transpirational pull for the transport of water.
• Supplies water for photosynthesis.
• Transports minerals from the soil to all parts of the plant.
• Cools the surface of the leaves by evaporation.
• Keeps the cells turgid; hence, maintains their shape.

Question 3.
Why are leucocytes classified as granulocytes and agranulocytes? Name each cell and mention its functions.
Answer:
Depending on the presence and absence of granules, leucoytes are divided into two types Granulocytes and Agranulocytes.
Granulocytes : They are characterised by the presence of granules in cytoplasm. The granulocytes include neutrophils, eosinophils and basophils.

1. Neutrophils : They constitute about 60-65% of total WBC’s. They are large and have many lobed nucleus. They are phagocytic in nature and appear in large,number in and around the infected tissue.
2. Eosinophils : They have bilobed nucleus and constitute about 2-3% of total WBC’s. Eosinophil increase during certain types of parasitic infection and allergic reaction. It bring about detoxification of toxin.
3. Basophils: Basophil have lobed nucleus. They form 0.5 – 1.0% of the total leucocytes. They release chemicals during the process of inflammation.

Agranulocytes : They are characterised by the absence of granules in the cytoplasm. These are of two types Lymphocytes and Monocytes.

1. Lymphocytes: These are about 20-25% of the total leucocytes. They produce antibodies during bacterial and viral infections.
2. Monocytes: They are the largest leucocytes and amoeboid in shape. These cells form 5-6% of the total leucocytes. They are phagocytic and can engulf bacteria.

Question 4.
Differentiate between systole and diastole. Explain the conduction of the heartbeat.
Answer:
One complete contraction (Systole) and relaxation (diastole) of the atrium and ventricles of the heart constitutes Heartbeat. The human heart is myogenic. Contraction is initiated by the sino – atrial (SA) node, which is situated in the wall of the right atrium, near the opening of the superior vena cava. SA node is broader at the top and tapering below and made up of thin fibres.

SA node acts as the ‘pacemaker’ of the heart because it is capable of initiating impulse which can stimulate the heart muscles to contract. The impulse spreads like a wave of contraction over the right and left atrial wall, pushing the blood, through the atrioventricular valves into the ventricles and the same wave from SA node reaches the atrioventricular node (AV), to emit an impulse of contraction, spreading to the ventricular muscle, through the atrioventricular bundle and the Purkinje fibres. The expansion of the artery every time, the blood is forced into the arteries, is called pulse. Normal pulse rate ranges from 70 – 90 / min.

Question 5.
Enumerate the functions of blood.
Answer:

1. Transport of respiratory gases (Oxygen and CO₂).
2. Transport of digested food materials to the different body cells.
3. Transport of hormones.
4. Transport of nitrogenous excretory products like ammonia, urea and uric acid.
5. It is involved in protection of the body and defense against diseases.
6. It acts as buffer and also helps in regulation of pH and body temperature.
7. It maintains proper water balance in the body.

IX. Assertion and Reasoning:

Direction: In each of the following questions a statement of assertion (A) is given and a corresponding statement of reason (R) is given just below it. Mark the correct statement as.
(a) If both A and R are true and R is correct explanation of A.
(b) If both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) Both A and R are false.
1. Assertion: RBC plays an important role in the transport of respiratory gases.
Reason: RBC do not have cell organelles and nucleus.
Answer:
(a) If both A and R are true and R is correct explanation of A.

2. Assertion: Persons with AB blood group are called an universal recipients, because they can receive blood from all groups.
Reason: Antibodies are absent in persons with AB blood group.
Answer:
(a) If both A and R are true and R is correct explanation of A.

X. Higher Order Thinking Skills (HOTS):

Question 1.
When any dry plant material is kept in water, they swell up. Name and define the phenomenon involved in this change.
Answer:
The process is imbibition’. The type of diffusion in which a solid absorbs water and gets swelled up is Imbibition.

Question 2.
Why are the walls of the left ventricle thicker than the other chambers of the heart?
Answer:
The walls of the left ventricle are about three times thicker than the right ventricle. The left ventricle gives rise to the aorta, which carries oxygenated blood, to various organs of the body. The ventricle walls are thick because they have to pump out blood with force away from the heart.

Question 3.
Doctors use stethoscope to hear the sound of the heart. Why?
Answer:
A stethoscope is an instrument used to detect the sound produced by the internal organs of human body. It is an useful diagnostic tool to identify and localize health problems and diagnose disease.

Question 4.
How do the pulmonary artery and pulmonary vein differ in their function when compared to a normal artery and vein?
Answer:

• All arteries carry oxygenated blood, except pulmonary arteries, which carry deoxygenated blood from the right ventricle to the lungs.
• All veins carry deoxygenated blood, except pulmonary veins, which carry oxygenated blood from the lungs and to the left atrium of the Heart.

Question 5.
Transpiration is a necessary evil in plants. Explain.
Answer:
The water is lost from the leaves due to transpiration, pressure is created in, at the top to pull more water from the xylem to the leaves through the process of transpiration pull. This ensure the continuous flow of water from the roots of the leaves.

Samacheer Kalvi 10th Science Transportation in Plants and Circulation in Animals Additional Important Questions and Answers

I. Choose the correct answer:

Question 1.
Seed swells when placed in water due to:
(a) osmosis
(b) imbibition
(c) hydrolysis
(d) all of these
Answer:
(b) imbibition

Question 2.
Root hairs occurs in:
(a) Meristematic zone
(b) Cell elongation zone
(c) Cell maturation zone
(d) Old root
Answer:
(c) Cell maturation zone

The other name for Red blood corpuscles (RBC) is called ______.
Answer:
Erythrocytes.

Question 3.
Water in plants is transported by ascent of sap takes place through:
(a) cambium
(b) xylem
(c) phloem
(d) epidermis
Answer:
(b) xylem

Question 4.
Absorption of water is increased when:
(a) transpiration is increased
(b) photosynthesis is increased
(c) respiration is increased
(d) root pressure is increased
Answer:
(a) transpiration is increased

Question 5.
Opening of stomata is due to:
(a) Turgidity of guard cells
(b) Size of guard cells
(c) Number of guard cells
(d) Amount of CO₂ in the atmosphere.
Answer:
(a) Turgidity of guard cells

Question 6.
Guard cells help in:
(a) Fighting against infection
(b) Guttation
(c) Protecting against grazing
(d) Transpiration
Answer:
(d) Transpiration

Question 7.
Photosynthetic food material is transported in the form of:
(a) Glucose
(b) Sucrose
(c) Starch
(d) Fructose
Answer:
(b) Sucrose

Question 8.
Coronary artery supplies blood to:
(a) Mammary glands
(b) Rib muscles
(c) Skin
(d) Heart
Answer:
(d) Heart

Question 9.
All arteries carry oxygenated blood except:
(a) systematic
(b) hepatic
(c) pulmonary
(d) cardiac
Answer:
(c) pulmonary

Question 10.
The colour of lymph is:
(a) white
(b) pale yellow
(c) colourless
(d) milky
Answer:
(c) colourless

Question 11.
An artery can be distinguished from a vein in having:
(a) thicker wall
(b) elastic vessels
(c) no valves
(d) all of the above
Answer:
(d) all of the above

Question 12.
Purkinje fibres mainly help in contraction of:
(a) right auricle
(b) left auricle
(c) ventricles
(d) Aorta
Answer:
(c) ventricles

Question 13.
The ‘Lubb’ and ‘Dupp’ heart sound are due to:
(a) opening of heart valves
(b) action of papillary’ muscles
(c) closing of heart valves
(d) activity of pace maker
Answer:
(c) closing of heart valves

Question 14.
The closed circulatory system occurs in:
(a) cockroach
(b) fish
(c) mosquito
(d) house fly
Answer:
(b) fish

Question 15.
Normal pulse rate is:
(a) 80 mm Hg
(b) 120 mm Hg
(c) 40 mg Hg
(d) 90 mm Hg
Answer:
(d) 90 mm Hg

Question 16.
In the ABO system of blood groups, of both antigens are present but no antibody, the blood group of the individual would be?
(a) B
(b) O
(c) AB
(d) A
Answer:
(c) AB

Question 17.
Arteries are branches of:
(a) capillaries
(b) veins
(c) aorta
(d) none of these
Answer:
(c) aorta

Question 18.
Which type of WBCs are found in maximum number?
(a) Monocytes
(b) Basophils
(c) Eosinophils
(d) Neutrophils
Answer:
(d) Neutrophils

Question 19.
Which of the following are granular WBCs?
(a) Neutrophils, Basophils, Lymphocytes
(b) Eosinophil, Basophil, Monocytes
(c) Basophils, Monocytes, Lymphocytes
(d) Neutrophils, Eosinophil, Basophil
Answer:
(d) Neutrophils, Eosinophil, Basophil

Question 20.
RBCs are concerned with carriage of gases.
(a) CO₂
(b) O₂
(c) Respiratory
(d) CO₂ and SO₂
Answer:
(c) Respiratory

II. Fill in the blanks:

1. The contraction of heart is called ………..
2. Oxygenated blood is carried by ………..
3. Sphygmomanometer measures ………..
4. Heart of man is ………..
5. Pace maker of heart is ………..
6. The life span of RBC in human is ……… days.
7. Pulmonary artery carry ………….. blood.
8. ………. discovered the circulation of blood in man.
9. Semilunar valve is present at the base of ………….
10. Human heart beats ………. times in a minute at rest.
11. Red blood pigment is ………..
12. Transpiration helps in the absorption and ………… movement of water and minerals.
13. Water in plants is transported by ascent of sap takes place through ……….
14. The absorption water due to expenditure of energy is called ………….
15. In plants, the translocation of organic solutes takes place through ………….
Answer:
1. systole
2. pulmonary vein
3. blood pressure
4. myogenic
5. sino atrial node
6. 120
7. deoxygenated
8. William Harvey
9. Pulmonary artery
10. 72
11. Haemoglobin
12. upward
13. xylem
14. active absorption
15. phloem

III. Match the following:

Question 1.
Match the Column I with Column II.

Answer:
A. (iv)
B. (iii)
C. (i)
D. (ii)

Question 2.
Match the Column I with Column II.

Answer:
A. (iv)
B. (iii)
C. (i)
D. (v)
E. (ii)

IV. State whether true or false. If false write the correct statement:

1. The human heart beats 72 times per minute.
2. Right half of heart receives and pu mps off oxygenated blood.
3. Between right auricle and right ventricle seen Mitral valve.
4. The force of attraction between water molecule is cohesion.
5. By passive transport sucrose moves into the cells where it is utilised or stored.

Answer:

1. True
2. False – Right half of heart receives and pumps off deoxygenated blood.
3. False – Between right auricle and right ventricle seen tricuspid valve.
4. True
5. False – By active transport sucrose moves into the cells where it is utilised or stored.

V. Creative Question:

Question 1.
Origin of heart beat and its conduction is represented by:
(a) AV node → Bundle of His → SA node → Purkinje fibres
(b) SA node → Purkinje fibres → AV node → Bundle of His
(c) Purkinje fibres → Purkinje node → AV fibres → Bundle of His
(d) SA node → AV node → Bundle of His → Purkinje fibres
Answer:
(d) SA node → AV node → Bundle of His → Purkinje fibres

Question 2.
The cardiac pacemaker in a patient fails to function normally. The doctors find that an artificial pacemaker is to be grafted in him. It is likely that it will be drafted at the site of:
(a) Purkinje system
(b) Sinu atrial node
(c) Atrio ventricular node
(d) Atrio ventricular bundle
Answer:
(b) Sinu atrial node

Question 3.
Doctor use stethoscope to hear the sounds produced during each cardiac cycle. The second sound is heard when:
(a) AV node receives signal from SA node
(b) AV valves open up
(c) Ventricular walls vibrate due to rushing in of blood from atria
(d) Semi lunar valves close down after the blood flows into vessels from ventricles
Answer:
(d) Semi lunar valves close down after the blood flows into vessels from ventricles

VI. Assertion and Reason:

(a) If both the assertion and the reason are true and the reason is the correct explanation of assertion.
(b) If both the assertion and the reason are true, but the reason is not the correct explanation of the assertion.
(c) Assertion is true, but the reason is false.
(d) Assertion is false, but the reason is true.
1. Assertion: RBC impart red colour to the blood due to the presence of respiratory pigment haemoglobin.
Reason: The young RBC contain nucleus in man.
Answer:
(b) If both the assertion and the reason are true, but the reason is not the correct explanation of the assertion.

2. Assertion: Osmosis is the movement of solvent molecule from higher concentration to lower concentration.
Reason: Osmosis is the active movement of water.
Answer:
(c) Assertion is true, but the reason is false.

VII. Answer in a Sentence:

Question 1.
Name the components of circulatory system.
Answer:
The circulation system consists of the circulating fluids, the blood and lymph, the heart and the blood vessels namely arteries, veins and capillaries.

Question 2.
What is the Ascent of Sap?
Answer:
The upward movement of water and minerals from roots to different plant parts is called ascent of sap.

Question 3.
Mention the composition of plasma.
Answer:
Organic substances like protein, glucose, urea, enzyme, hormones, vitamins and minerals are present in plasma.

Question 4.
Define Adhesion?
Answer:
The force of attraction between molecules of different substances is called adhesion.

Question 5.
Why are auricles and ventricles separated by auricular and ventricular septum?
Answer:
The separation of chamber avoids mixing of oxygenated and deoxygenated blood.

Question 6.
What is Single Circulation?
Answer:
In fishes, amphibians and certain reptiles, the oxygenated and deoxygenated blood are mixed ‘ and pass through the heart only once, is called Single Circulation.

Question 7.
Name the instruments used to measure blood pressure.
Answer:
Sphygmomanometer is a clinical instruments used to measure blood pressure when a person is in a relaxed and resting condition. Normal blood pressure in human is 120 mm/ 80 mm Hg.

Question 8.
Which blood group is called as ‘Universal Donor’ and ‘Universal Recipient’.
Answer:
Person with ‘O’ blood group are called Universal Donor.
Person with ‘AB’ blood group are called Universal Recipient.

Question 9.
What is Pulse?
Answer:
During the expansion of the artery, every time, the blood is forced into the arteries is called pulse.

Question 10.
What is transpiration puil?
Answer:
Transpiration through stomata creates vacuum which creates a suction called transpiration pull.

Question 11.
What are Rh antibodies?
Answer:
Rh-negative persons do not have Rh antigen on the surface of RBC. Antibodies developed against this Rh antigen is called Rh antibodies.

Question 12.
What is Adhesion?
Answer:
The force of attraction between molecules of different substances is called . adhesion.

VIII. Short answer question:

Question 1.
What is blood pressure?
Answer:
Blood pressure is the force exerted during the flow of blood against the lateral walls of arteries. The blood pressure is high in the arteries gradually drop in the arterioles and capillaries and become very low in the veins. Blood pressure varies during conditions of physical exercise, anxiety, emotions, stress and sleep. Increase in blood pressure is known as hypertension and decrease in blood pressure is termed as hypotension.

Question 2.
Distinguish between open and closed circulation.
Answer:

Question 3.
Explain the phenomenon of Guttation.
Answer:
The Guttation is a phenomenon caused due to root pressure. It takes place through a specialized cells called hydathodes. Dews on the leaves of grass seen in the early morning, when the climate is humid and excess of water in the soil is an example of Guttation.

Question 4.
What is Coronary circulation?
Answer:
The supply of blood to the heart muscles is called as coronary circulation. Cardiac muscles receives oxygenated blood from coronary arteries that originate from the aortic arch. Deoxygenated blood from the cardiac muscles drains into the right atrium by the coronary sinuses.

IX. Long answer questions:

Question 1.
What is lymph? Write its functions.
Answer:
Lymph is a colourless fluid formed when plasma, proteins and blood cells escape into intercellular spaces in the tissues through the pores present in the walls of capillaries.
Functions of Lymph:

1. Supplies nutrition and oxygen to those parts where blood cannot reach.
2. It drains away excess tissue fluid and metabolites and returns proteins to the blood from tissue spaces.
3. The lymph also carries absorbed fats from small intestine to the blood. The lymphatic capillaries of intestinal villi (lacteals) absorb digested fats.
4. Lymphocytes in the lymph defend the body from infections.

Question 2.
(a) Name the main two components of blood.
(b) What does plasma contain?
Answer:
(a) 1. The fluid plasma
2. Formed elements (blood cells)

• RBC
• WBC
• Blood platelets

(b) Plasma is slightly alkaline, containing non – cellular substance, constitute 55 % of the blood. Organic substances like Proteins, Glucose, Urea, Enzymes, Hormones, Vitamins and Minerals are present in the Plasma.

Question 3.
Demonstrate the process of osmosis with thistle funnel.
Answer:
Aim : To demonstrate the process of osmosis, using Thistle funnel.
Materials Required : Beaker, Thistle funnel, semi permeable membrane, sucrose solution.
Procedure : A thistle funnel whose mouth is covered with a semipermeable membrane, is filled with sucrose solution. It is kept inverted in a beaker containing water.
Observation : The water will diffuse across the membrane due to osmosis and raise the level of the solution in the funnel.
Inference : Raise of liquid in the funnel indicates the process of osmosis.

Question 4.
Explain Double circulation.
Answer:
Diagrammatic representation of the double circulation.

Question 5.
Explain the steps involved in Ascent of sap.
Answer:
The upward movement of water, and minerals from roots to different plant parts is called ascent of sap. A number of factors play a role in ascent of sap and it takes places in following steps.
Root Pressure : Water from soil enters the root hairs due to osmosis. Root pressure is responsible for movement of water up to the base of the stem.

Capillary Action : Water or any liquid rises in a capillary tube because of physical forces, this phenomenon is called capillary action. In the same way, in stem water rises up to certain height because of capillary’ action.
Adhesion-cohesion of Water Molecules : Water molecules form a continuous column in the xylem because of forces of adhesion and cohesion among the molecules.
Cohesion : The force of attraction between molecules of water is called cohesion.
Adhesion : The force of attraction between molecules of different substances is called adhesion.Water molecules stick to a xylem because of force of adhesion.

Question 6.
Explain the causes of the sound of the Heart.
Answer:
The rhythmic closure and opening of the valves cause the sound of the heart.

• The first sound ‘LUBB’ is produced by the closure of the tricuspid and bicuspid valves, after the beginning of ventricular systole. It is a longer duration.
• The second sound ‘DUPP’ is produced by the closure of semilunar valves, at the end of ventricular systole. It is of short duration.

X. Higher Order Thinking Skills (HOTS)

Question 1.
An unconscious patient is rushed into the emergency room and need a fast blood transfusion. Because there is no time to check her medical history or determine her blood type, which type of blood should you as her doctor, give?
Answer:
O^+ve, it is universal donor. In O group individuals, Antigen A or B are absent on the surface of RBC. However the plasma contains both antibodies a and b.

Question 2.
What are the factors affecting the Ascent of Sap?
Answer:

• High Temperature
• Atmospheric Pressure
• Wind Velocity
• Low atmospheric humidity
• Soil water deficit.

Question 3.
Water vapour comes out from the plant leaf through the stomatal opening. Through the same stomatal opening carbon dioxide diffuses into the plant during photosynthesis. Reason out the above statements.
Answer:
Both processes can happen together because the diffusion co-efficient of water and CO₂ is different.

Question 4.
Write a few Strategies, to prevent heart disease.
Answer:

• Exercise for about 30 minutes every day.
• Smoking or use of Tobacco should be avoided.
• Eat a heart-healthy diet – Avoid too much of salt or sugar, use of a diet rich in Vegetables and Fruits.
• Maintain a healthy weight.
• Get enough quality sleep.
• Manage Stress.
• Get regular health screenings (B.P. monitoring, Cholesterol level, Diabetes Screening etc.).

XI. Give reason:

Question 1.
Valves are important in human heart. Give reason.
Answer:
The valves will prevent the back flow of blood.

Question 2.
During rainy season wooden door generally swells up – Give reason.
Answer:
It is due to imbibition. It is a type of diffusion in which a solid absorbs water and gets swelled up.

Question 3.
Para sympathetic neural signals affects the working of the heart. Give reason.
Answer:
It reduce both heart rate and cardiac output.

Question 4.
Grapes placed in salt solution shrink. Give reason.
Answer:
It is due to exosmosis.

Question 5.
Why WBC’s are known as phagocytes?
Answer:
WBC produce antibodies during bacterial and viral infection and engulf the germs.

Students can Download Tamil Nadu 12th Physics Model Question Paper 5 English Medium Pdf, Tamil Nadu 12th Physics Model Question Papers helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

TN State Board 12th Physics Model Question Paper 5 English Medium

General Instructions:

• The question paper comprises of four parts.
• You are to attempt all the parts. An internal choice of questions is provided wherever applicable.
• All questions of Part I, II, III, and IV are to be attempted separately.
• Question numbers 1 to 15 in Part I are Multiple Choice Questions of one mark each.
  These are to be answered by choosing the most suitable answer from the given four
  alternatives and writing the option code and the corresponding answer
• Question numbers 16 to 24 in Part II are two-mark questions. These are to be answered
  in about one or two sentences.
• Question numbers 25 to 33 in Part III are three-mark questions. These are to be answered
  in about three to five short sentences.
• Question numbers 34 to 38 in Part IV are five-mark questions. These are to be answered
  in detaiL Draw diagrams wherever necessary.

Time: 3 Hours
Max Marks: 70

Part – I

Answer all the questions. Choose the correct answer. [15 x 1 = 15]

Question 1.
If voltage applied on a capacitor is increased from V to 2V, Choose the correct conclusion,
(a) Q remains the same, C is doubled
(b) Q is doubled, C doubled
(c) C remains same, Q doubled
(d) Both Q and C remain same
Answer:
(c) C remains same, Q doubled

Question 2.
The electric field in the region between two concentric charged spherical shells
(a) is zero
(b) increases with distance from centre
(c) is constant
(d) decreases with distance from centre
Answer:
(d) decreases with distance from centre

Question 3.
In India electricity is supplied for domestic use at 220 V. It is supplied at 110 V in USA. If the resistance of a 60W bulb for use in India is R, the resistance of a 60W bulb for use in USA will be …………
(a) R
(b) 2R
(c) \(\frac{\mathbf{R}}{4}\)
(d) \(\frac{\mathbf{R}}{2}\)
Answer:
(c) \(\frac{\mathbf{R}}{4}\)

Question 4.
The vertical component of Earth’s magnetic field at a place is equal to the horizontal component. What is the value of angle of dip at this place?
(a) 30°
(b) 45°
(c) 60°
(d) 90°
Answer:
(b) 45°

Question 5.
A step-down transformer reduces the supply voltage from 220 V to 11 V and increase the current from 6 A to 100 A. Then its efficiency is
(a) 1.2
(b) 0.83
(c) 0.12
(d) 0.9
Answer:
(b) 0.83

Question 6.
Faraday’s law of electromagnetic induction is related to the …………….
(a) Law of conservation of charge
(b) Law of conservation of energy
(c) Third law of motion
(d) Law of conservation of angular momentum
Answer:
(b) Law of conservation of energy

Question 7.
The dimension of \(\frac{1}{\mu_{0} \varepsilon_{0}}\) is ……….
(a) [L T^-1]
(b) [L² T^-2]
(c) [L^-1 T]
(d) [L^-2 T²]
Answer:
(b) [L² T^-2]

Question 8.
In a Young’s double-slit experiment, the slit separation is doubled. To maintain the same fringe spacing on the screen, the screen-to-slit distance D must be changed to,…………..
(a) 2D
(b) \(\frac{\mathrm{D}}{2}\)
(c) \(\sqrt{2} \mathrm{D}\)
(d) \(\frac{\mathrm{D}}{\sqrt{2}}\)
Answer:
(a) 2D

Question 9.
The speed of light in an isotropic medium depends on,
(a) its intensity
(b) its wavelength
(c) the nature of propagation
(d) the motion of the source w.r.to medium
Answer:
(b) its wavelength

Question 10.
The mean wavelength of light from sun is taken to be 550 nm and its mean power is 3.8 x 10²⁶ W. The number of photons received by the human eye per second on the average from sunlight is of the order of ……………..
(a) 10⁴⁵
(b) 10⁴²
(c) 10⁵⁴
(d) 10⁵¹
Answer:
(a) 10⁴⁵
Hint:

Question 11.
As the intensity of incident light increases
(a) kinetic energy of emitted photoelectrons increases
(b) photoelectric current decreases
(c) photoelectric current increases
(d) kinetic energy of emitted photoelectrons decreases
Answer:
(c) photoelectric current increases
Hint: As the intensity of incident light increases, photoelectric current increases.

Question 12.
In J.J. Thomson e/m experiment, a beam of electron is replaced by that of muons (particle with same charge as that of electrons but mass 208 times that of electrons). No deflection condition is achieved only if
(a) B is increased by 208 times
(b) B is decreased by 208 times
(c) B is increased by 14.4 times
(d) B is decreased by 14.4 times
Answer:
(c) B is increased by 14.4 times
Hint: In the condition of no deflection \(\frac{e}{m}=\frac{\mathrm{E}^{2}}{2 v \mathrm{B}^{2}}\)
If m is increased by 208 times then B should be increased \(\sqrt{208}\) = 14.4 times

Question 13.
A forward biased diode is treated as
(a) An open switch with infinite resistance
(b) A closed switch with a voltage drop of 0V
(c) A closed switch in series with a battery voltage of 0.7V
(d) A closed switch in series with a small resistance and a battery.
Answer:
(d) A closed switch in series with a small resistance and a battery.

Question 14.
The variation of frequency of carrier wave with respect to the amplitude of the modulating
signal is called …………
(a) Amplitude modulation
(b) Frequency modulation
(c) Phase modulation
(d) Pulse width modulation
Answer:
(b) Frequency modulation

Question 15.
Who is the father of the modem robotics industry formed the world’s first robotic company in 1956?
(a) Joliot
(b) Cormark
(c) Engelberger
(d) Edward purcell
Answer:
(c) Engelberger

Part – II

Answer any six questions in which Q. No 17 is compulsory.

Question 16.
What is the general definition of electric dipole moment?
Answer:
The electric dipole moment vector lies along the line joining two charges and is directed from  – q to +q. The SI unit of dipole moment is coulomb meter (cm).
\(\vec{p}=q a \hat{i}-q a(-\hat{i})=2 q a \hat{i}\)

Question 17.
Calculate the electric flux through the rectangle of sides 5 cm and 10 cm kept in the region of a uniform electric field 100 NC^-1. The angle 0 is 60°. Suppose 0 becomes zero, what is the electric flux?
Answer:

Question 18.
What is meant by hysteresis?
Answer:
The phenomenon of lagging of magnetic induction behind the magnetising field is called hysteresis. Hysteresis means Tagging behind’.

Question 19.
What is meant by wattles current?
Answer:
The component of current (I_pMS sin φ), which has a phase angle of \(\frac{\pi}{2}\) with the voltage is called reactive component. The power consumed is zero. So that it is also known as ‘Wattless’ current.

Question 20.
What is Snell’s window?
Answer:
When light entering the water from outside is seen from inside the water, the view is restricted to a particular angle equal to the critical angle i_c. The restricted illuminated circular area is called Snell’s window.

Question 21.
Define work function of a metal. Give its unit.
Answer:
The minimum energy needed for an electron to escape from the metal surface is called work function of that metal. It’s unit is electron volt (eV).

Question 22.
What is meant by radioactivity?
Answer:
The phenomenon of spontaneous emission of highly penetrating radiations such as α, β and γ rays by an element is called radioactivity.

Question 23.
What is the angular momentum of an electron in the third orbit of an atom?
Answer:
Here n = 3; h = 6.6 x 10^-34 Js
Angular momentum.

Question 24.
Explain the current flow in a NPN transistor
Answer:

• The conventional flow of current is based on the direction of the motion of holes
• In NPN transistor, current enters from the base into the emitter.

Part – III

Answer any six questions in which Q.No. 27 is compulsory. [6×3 = 18]

Question 25.
Define ‘capacitance’. Give its unit.
Answer:
The capacitance C of a capacitor is defined as the ratio of the magnitude of charge on either of the conductor plates to the potential difference existing between the conductors.
\(C=\frac{Q}{V} \text { or } Q \propto V\)
The SI unit of capacitance is coulomb per volt or farad (F).

Question 26.
Distinguish between drift velocity and mobility
Answer:

SNo.	Drift Velocity	Mobility
1.	The drift velocity is the average velocity acquired by the electrons inside the conductor when it is subjected to an electric field.	Mobility of an electron is defined as the magnitude of the drift velocity per unit electric field.
2.	\(\overrightarrow{\mathrm{V}}_{d}=\vec{a} \tau\)	\(\mu=\frac{e \tau}{m} \text { or } \mu=\frac{\left|\overrightarrow{\mathrm{V}}_ {d}\right|}{\overrightarrow{\mathrm{E}}}\)
3.	It’s unit is ms-1.	It’s unit is m2 v_1 s_1

Question 27.
A coil of a tangent galvanometer of diametre 0.24 m has 100 turns. If the horizontal component of Earth’s magnetic field is 25 x 10^-6 T then, calculate the current which gives a deflection of 60°.
Answer:
The diameter of the coil is 0.24 m. Therefore, radius of the coil is 0.12 m.
Number of turns is 100 turns. Earth’s magnetic field is 25 x 10^-6 T

Question 28.
Mention the ways of producing induced emf.
Answer:
Induced emf can be produced by changing magnetic flux in any of the following ways:

• By changing the magnetic field B
• By changing the area A of the coil and
• By changing the relative orientation 0 of the coil with magnetic field

Question 29.
A 400 mH coil of negligible resistance is connected to an AC circuit in which an effective current of 6 mA is flowing. Find out the voltage across the coil if the frequency is 1000 Hz.
Answer:
L = 400 x 10^-3 H; I_eff = 6 x 10^-3A; f= 1000 Hz
Inductive reactance, X_L = Lω = L x 2πf = 2 x 3.14 x 1000 x 0.4 = 2512Ω
Voltage across L, V – IX_L = 6 x 10^-3 x 2512 =15.072 V (RMS)

Question 30.
What are the sign conventions followed for lenses?
Answer:
The sign conventions for thin lenses differ only in the signs followed for focal lengths.
(a) The sign of focal length is not decided on the direction of measurement of the focal length from the pole of the lens as they have two focal lengths, one to the left and another to the right (primary and secondary focal lengths on either side of the lens).

(b) The focal length of the thin lens is taken as positive for a converging lens and negative for a diverging lens.

Question 31.
Write down the draw backs of Bohr atom’model.
Answer:
Limitations of Bohr atom model
The following are the drawbacks of Bohr atom model

• Bohr atom model is valid only for hydrogen atom or hydrogen like-atoms but not for
  complex atoms.
• When the spectral lines are closely examined, individual lines of hydrogen spectrum is
  accompanied by a number of faint lines. These are often called fine structure. This is not explained by Bohr atom model.
• Bohr atom model fails to explain the intensity variations in the spectral lines.
• The distribution of electrons in atoms is not completely explained by Bohr atom model.

Question 32.
What do you mean by leakage current in a diode?
Answer:
The leakage current in a diode is the current that the diode will leak when a reverse voltage is applied to it. Under the reverse bias, a very small current in μA, flows across the junction. This is due to the flow of the minority charge carriers called the leakage current or reverse saturation current.

Question 33.
Distinguish between wireline and wireless communication.
Answer:

Wireline communication	Wireless communication
It is a point-to-point communication.	It is a broadcast mode communication.
It uses mediums like wires, cable and optical fibres.	It uses free space as a communication medium.
These systems cannot be used for long distance transmission as they are connected.	These systems can be used for long distance transmission.
Ex. telephone, intercom and cable TV.	Ex. mobile, radio or TV broadcasting and satellite communication.

Part – IV

Answer all the questions. [5 x 5 = 25]

Question 34.
(a) Derive an expression for the torque experienced by a dipole due to a uniform electric field.
Answer:
Torque experienced by an electric dipole in the uniform electric field: Consider an electric dipole of dipole moment \(\vec{p}\) placed in a uniform electric field \(\vec{E}\) whose field lines are equally spaced and point in the same direction. The charge +q will experience a force q\(\vec{E}\)  in the direction of the field and charge -q will experience a force -q \(\vec{E}\) in a direction opposite to the field. Since the external field \(\vec{E}\) is uniform, the total force acting on the dipole is zero. These two forces acting at different points will constitute a couple and the dipole experience a torque. This torque tends to rotate the dipole. (Note that electric field lines of a uniform field are equally spaced and point in the same direction). The total torque on the dipole about the point O.

Using right-hand corkscrew rule, it is found that total torque is perpendicular to the plane of the paper and is directed into it.
The magnitude of the total torque


where θ is the angle made by \(\vec{p} \text { with } \overrightarrow{\mathrm{E}}\) .
Since p = 2aq, the torque is written in terms of the vector product as \(\vec{\tau}=\vec{p} \times \vec{E}\)
The magnitude of this torque is τ = pE sin θ and is maximum
when θ =90°.
This torque tends to rotate the dipole and align it with the electric field [/latex]\overrightarrow{\mathrm{E}}[/latex] . Once \(\overrightarrow{\mathrm{p}}\) is aligned with \(\overrightarrow{\mathrm{E}}\), the total torque on the dipole becomes zero.

[OR]

(b) Explain the equivalent resistance of a parallel resistor network.
Answer:
Resistors in parallel: Resistors are in parallel when they are connected across the same potential difference as shown in fig. (a).
In this case, the total current I that leaves the battery in split into three separate paths. Let I₁, I₂ and I₃ be the current through the resistors R_{1 ,}R₂ and R₃ respectively. Due to the conservation of charge, total current in the circuit I is equal to sum of the currents through each of the three resistors.
I = I_{1 +} I₂ + I₃ ………………… (1)

Since the voltage across each resistor is the same, applying Ohm’s law to each resistor, we have

Substituting these values in equation (1) we get.

Here R_p is the equivalent resistance of the parallel combination of the resistors. Thus, when a number of resistors are connected in parallel, the sum of the reciprocal of the values of resistance of the individual resistor is equal to the reciprocal of the effective resistance of the combination as shown in the fig. (b).
Note: The value of equivalent resistance in parallel connection will be lesser than each individual resistance.

Question 35.
(a) Obtain a relation for the magnetic induction at a point along the axis of a circular coil ‘ carrying current.
Answer:
Magnetic field produced along the axis of the current carrying circular coil: Consider a current carrying circular loop of radius R and let I be the current flowing through the wire in the direction. The magnetic field at a point P on the axis of the circular coil at a distance z from its center of the coil O. It is computed by taking two diametrically opposite line elements of the coil each of length \(d \bar{l} \) at C and D Let r be the vector joining the current element (I \(d \bar{l}\)) at C to the point P.
PC = PD = r = \(r=\sqrt{\mathrm{R}^{2}+\mathrm{Z}^{2}}\)
PC = PD = r = \(r=\sqrt{\mathrm{R}^{2}+\mathrm{Z}^{2}}\)
angle ∠CPO = ∠DPO = θ
According to Biot-Savart’s law, the magnetic field at P due to the current element \(d \bar{l} \) is


The magnitude of magnetic field due to current element I \(d \bar{l} \) at C and D are equal because of equal distance from the coil. The magnetic field dB due to each current element I dl is resolved into two components; dB sin θ along y-direction and dB cos θ along the z-direction. Horizontal components of each current element cancels out while the vertical components (dB cos θ \(\hat{k}\) ) alone contribute to total magnetic field at the point P.
If we integrate \(d \bar{l} \) around the loop, \(d \bar{B} \) sweeps out a cone, then the net magnetic field \(\overrightarrow{\mathrm{B}}\) at point P is

Using Pythagorous theorem r² = R² + Z² and integrating line element from 0 to 2πR, we get

Note that the magnetic field \(\bar{B} \) points along the direction from the point O to P. Suppose if the current flows in clockwise direction, then magnetic field points in the direction from the point P to O.

[OR]

(b) Explain the working of a single-phase AC generator with necessary diagram.
Answer:
Single phase AC generator: In a single phase AC generator, the armature conductors are connected in series so as to form a single circuit which generates a single-phase alternating emf and hence it is called single-phase alternator.

The simplified version of a AC generator is discussed hire. Consider a stator core consisting of 2 slots in which 2 armature conductors PQ and RS are mounted to form single-turn rectangular loop PQRS. Rotor has 2 salient poles with field windings which can be magnetized by means of DC source.

Working: The loop PQRS is stationary and is perpendicular to the plane of the paper. When field windings are excited, magnetic field is produced around it. The direction of magnetic field passing through the armature core. Let the field magnet be rotated in clockwise direction by the prime mover. The axis of rotation is perpendicular to the plane of the paper.

Assume that initial position of the field magnet is horizontal. At that instant, the direction of magnetic field is perpendicular to the plane of the loop PQRS. The induced emf is zero. This is represented by origin O in the graph between induced emf and time angle.

When field magnet rotates through 90°, magnetic field becomes parallel to PQRS. The induced emfs across PQ and RS would become maximum. Since they are connected in series, emfs are added up and the direction of total induced emf is given by Fleming’s right hand rule.

Care has to be taken while applying this rule; the thumb indicates the direction of the motion of the conductor with respect to field. For clockwise rotating poles, the conductor appears to be rotating anti-clockwise. Flence, thumb should point to the left. The direction of the induced emf is at right angles to the plane of the paper. For PQ, it is downwards and for RS upwards. Therefore, the current flows along PQRS. The point A in the graph represents this maximum emf.

For the rotation of 180° from the initial position, the field is again perpendicular to PQRS and the induced emf becomes zero. This is represented by point B. The field magnet becomes again parallel to PQRS for 270° rotation of field magnet. The induced emf is maximum but the direction is reversed. Thus the current flows along SRQP. This is represented by point C.

On completion of 360°, the induced emf becomes zero and is represented by the point D. From the graph, it is clear that emf induced in PQRS is alternating in nature.

Therefore, when field magnet completes one rotation, induced emf in PQRS finishes one cycle. For this construction, the frequency of the induced emf depends on the speed at which the field magnet rotates.

Question 36.
(a) What is emission spectra? Give their types.
Answer:
Emission spectra: When the spectrum of self luminous source is taken, we get emission spectrum. Each source has its own characteristic emission spectrum. The emission spectrum _ can be divided into three types:

(i) Continuous emission spectra (or continuous spectra): If the light from incandescent lamp filament bulb) is allowed to pass through prism (simplest spectroscope), it splits into seven colours. Thus, it consists of wavelengths containing all the visible colours ranging from violet to red. Examples: spectrum obtained from carbon arc, incandescent solids, liquids gives continuous spectra.

(ii) Line emission spectrum (or line spectrum): Suppose light from hot gas is allowed to pass through prism, line spectrum is observed. Line spectra are also known as discontinuous spectra. The line spectra are sharp lines of definite wavelengths or frequencies. Such spectra arise due to excited atoms of elements. These lines are the characteristics of the element which means it is different for different elements. Examples: spectra of atomic hydrogen, helium, etc.

(iii) Band emission spectrum (or band spectrum): Band spectrum consists of several number of very closely spaced spectral lines which overlapped together forming specific bands which are separated by dark spaces, known as band spectra. This spectrum has a sharp edge at one end and fades out at the other end. Such spectra arise when the molecules are excited. Band spectrum is the characteristic of the molecule hence, the structure of the molecules can be studied using their band spectra. Examples, spectra of hydrogen gas, ammonia gas in the discharge tube etc.

[Or]

(b) Describe the Fizeau’s method to determine speed of light.
Answer:
Fizeau’s method to determine speed of light:
Apparatus: The light from the source S was first allowed to fall on a partially silvered glass plate G kept at an angle of 45° to the incident light from the source. The light then was allowed to pass through a rotating toothed-wheel with N teeth and N cuts of equal widths whose speed of rotation could be varied through an external mechanism.

The light passing through one cut in the wheel will, get reflected by a mirror M kept at a long distance d, about 8 km from the toothed wheel. If the toothed wheel was not rotating, the reflected light from the mirror would again pass through the same cut and reach the eyes of the observer through the partially silvered glass plate.

Working: The angular speed c rotation of the toothed wheel was increased from zero to a value co until light passing through one cut would completely be blocked by the adjacent tooth. This is ensured by the disappearance of light while looking through the partially silvered glass plate.

Expression for speed of light: The speed of light in air v is equal to the ratio of the distance the light travelled from the toothed wheel to the mirror and back 2d to the time taken t.
\(v=\frac{2 d}{t}\) ………………… (1)

The distance d is a known value from the arrangement. The time taken t for the light to travel the distance to and fro is calculated from the angular speed ω of the toothed wheel. The angular speed ω of the toothed wheel when the light disappeared for the first time is,
\(\omega=\frac{\theta}{t}\) ………………….. (2)

Here, θ is the angle between the tooth and the slot which is rotated by the toothed wheel within that time t

Rewriting the above equation for t
\(t=\frac{\pi}{\mathrm{N} \omega}\) ……………….. (3)
Substituting t from equation (3) in equation (1)
\(v=\frac{2 d}{\pi / \mathrm{N} \omega}\)
\(v=\frac{2 d \mathrm{N} \omega}{\pi}\) …………….(4)
Fizeau had some difficulty to visually estimate the minimum intensity blocked by the adjacent tooth, and his value for speed of light was very value.

Question 37.
(a) List out the laws of photoelectric effect.
Answer:
Laws of photoelectric effect:

• For a given frequency of incident light, the number of photoelectrons emitted is directly proportional to the intensity of the incident light. The saturation current is also directly proportional to the intensity of incident light.
• Maximum kinetic energy of the photo electrons is independent of intensity of the incident light.
• Maximum kinetic energy of the photo electrons from a given metal is directly proportional to the frequency of incident light.
• For a given surface, the emission of photoelectrons takes place only if the frequency of incident light is greater than a certain minimum frequency called the threshold frequency.
• There is no time lag between incidence of light and ejection of photoelectrons.

[OR]

(b) Describe the working of nuclear reactor with a block diagram.
Answer:
Nuclear reactor:

• Nuclear reactor is a system in which the nuclear fission takes place in a self-sustained controlled manner and the energy produced is used either for research purpose or for power generation.
• The main parts of a nuclear reactor are fuel, moderator and control rods. In addition to this, there is a cooling system which is connected with power generation set up.

Fuel:

• The fuel is fissionable material, usually uranium or plutonium. Naturally occurring uranium contains only \(0.7 \% \text { of }_{92}^{235} \mathrm{U} \text { and } 99.3 \% \text { are only }^{238} \mathrm{g}_{2} \mathrm{U}\) . So the \(_{ 92 }^{ 235 }{ U }\) must be enriched such that it contains at least 2 to 4% of \(_{ 92 }^{ 235 }{ U }\) .
• In addition to this, a neutron source is required to initiate the chain reaction for the first time. A mixture of beryllium with plutonium or polonium is used as the neutron source. During fission of \(_{ 92 }^{ 235 }{ U }\), only fast neutrons are emitted but the probability of initiating fission by it in another nucleus is very low. Therefore, slow neutrons are preferred for sustained nuclear reactions.

Moderators:

• The moderator is a material used to convert fast neutrons into slow neutrons. Usually the moderators are chosen in such a way that it must be very light nucleus having mass comparable to that of neutrons. Hence, these light nuclei undergo collision with fast neutrons and the speed of the neutron is reduced
• Most of the reactors use water, heavy water (D₂0) and graphite as moderators. The blocks of uranium stacked together with blocks of graphite (the moderator) to form a large pile.

 

Control rods:

• The control rods are used to adjust the reaction rate. During each fission, on an average 2.5 neutrons are emitted and in order to have the controlled chain reactions, only one neutron is allowed to cause another fission and the remaining neutrons are absorbed by the control rods.
• Usually cadmium or boron acts as control rod material and these rods are inserted into the uranium blocks. Depending on the insertion depth of control rod into the uranium, the average number of neutrons produced per fission is set to be equal to one or greater than one.
• If the average number of neutrons produced per fission is equal to one, then reactor is said to be in critical state. In fact, all the nuclear reactors are maintained in critical state by suitable adjustment of control rods. If it is greater than one, then reactor is said to be in super-critical and it may explode sooner or may cause massive destruction.

Shielding:

• For a protection against harmful radiations, the nuclear reactor is surrounded by a concrete wall of thickness of about 2 to 2.5 m.

Cooling system:

• The cooling system removes the heat generated in the reactor core. Ordinary water, heavy water and liquid sodium are used as coolant since they have very high specific heat capacity and have large boiling point under high pressure.
• This coolant passes through the fuel block and carries away the heat to the steam generator through heat exchanger. The steam runs the turbines which produces electricity in power reactors.

Question 38.
(a) Explain the working principle of a solar cell. Mention its applications.
Answer:
Solar cell:
A solar cell, also known as photovoltaic cell, converts light energy directly into electricity or electric potential difference by photovoltaic effect. It is basically a p-n junction which generates emf when solar radiation falls on the p-n junction. A solar cell is of two types: p-type and n-type.

Both types use a combination of p-type and n-type Silicon which together forms the p-n junction of the solar cell. The difference is that p-type solar cells use p-type Silicon as the base with an ultra-thin layer of n-type Silicon as shown in Figure, while n-type solar cell uses the opposite combination. The other side of the p-Silicon is coated with metal which forms the back electrical contact. On top of the n-type Silicon, metal grid is deposited which acts as the front electrical contact. The top of the solar cell is coated with anti-reflection coating and toughened glass.

In a solar cell, electron-hole pairs are generated due to the absorption of light near the junction. Then the charge carriers are separated due to the electric field of the depletion region. Electrons move towards n-type Silicon and holes move towards p-type Silicon layer.

The electrons reaching the n-side are collected by the front contact and holes reaching p-side are collected by the back electrical contact. Thus a potential difference is developed across solar cell. When an external load is connected to the solar cell, photocurrent flows through the load.

Many solar cells are connected together either in series or in parallel combination to form solar panel or module. Many solar panels are connected with each other to form solar arrays. For  high power applications, solar panels and solar arrays are used.

Applications:

• Solar cells are widely used in calculators, watches, toys, portable power supplies, etc.
• Solar cells are used in satellites and space applications
• Solar panels are used to generate electricity.

(b) Elaborate on the basic elements of communication system with the necessary block diagram.
Answer:
Elements of an electronic communication system
Information (Baseband or input signal): Information can be in the form of a sound signal like speech, music, pictures, or computer data which is given as input to the input transducer.

Input transducer
A transducer is a device that converts variations in a physical quantity (pressure, temperature, sound) into an equivalent electrical signal or vice versa. In communication system, the transducer converts the information which is in the form of sound, music, pictures or computer data into corresponding electrical signals. The electrical equivalent of the original information is called the baseband signal. The best example for the transducer is the microphone that converts sound energy into electrical energy.

Transmitter:
It feeds the electrical signal from the transducer to the communication channel. It consists of circuits such as amplifier, oscillator, modulator, and power amplifier. The transmitter is located at the broadcasting station.

Amplifier:
The transducer output is very weak and is amplified by the amplifier. Oscillator: It generates high-frequency carrier wave (a sinusoidal wave) for long distance transmission into space. As the energy of a wave is proportional to its frequency, the carrier wave has very high energy.

Modulator:
It superimposes the baseband signal onto the carrier signal and generates the modulated signal.

Power amplifier:
It increases the power level of the electrical signal in order to cover a large distance.

Transmitting antenna:
It radiates the radio signal into space in all directions. It travels in the form of electromagnetic waves with the velocity of light (3 ^x 10⁸ ms^-1).

Communication channel:
Communication channel is used to carry the electrical signal from transmitter to receiver with less noise or distortion. The communication medium is basically of two types: wireline communication and wireless communication.

Noise:
It is the undesirable electrical signal that interfaces with the transmitted signal. Noise attenuates or reduces the quality of the transmitted signal. It may be man-made (automobiles, welding machines, electric motors etc .) or natural (lightening, radiation from sun and stars and environmental effects). Noise cannot be completely eliminated. However, it can be reduced using various techniques.

Receiver:
The signals that are transmitted through the communication medium are received with the help of a receiving antenna and are fed into the receiver. The receiver consists of electronic circuits like demodulator, amplifier, detector etc. The demodulator extracts the baseband signal from the carrier signal. Then the baseband signal is detected and amplified using amplifiers. Finally, it is fed to the output transducer.

Repeaters:
Repeaters are used to increase the range or distance through which the signals are sent. It is a combination of transmitter and receiver. The signals are received, amplified, and retransmitted with a carrier signal of different frequency to the destination. The best example is the communication satellite in space.

Output transducer:
It converts the electrical signal back to its original form such as sound, music, pictures or data. Examples of output transducers are loudspeakers, picture tubes, computer monitor, etc.

Attenuation:
The loss of strength of a signal while propagating through a medium is known as attenuation.

Range:
It is the maximum distance between the source and the destination up to which the signal is received with sufficient strength.

Students can download 10th Science Chapter 13 Structural Organisation of Animals Questions and Answers, Notes, Samacheer Kalvi 10th Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 13 Structural Organisation of Animals

Samacheer Kalvi 10th Science Structural Organisation of Animals Text Book Back Questions and Answers

I. Choose the best answer:

Question 1.
In leech locomotion is performed by:
(a) Anterior sucker
(b) Posterior sucker
(c) Setae
(d) None of the above
Answer:
(a) Anterior sucker

Question 2.
The segments of leech are known as _____.
(a) Metameres (somites)
(b) Proglottids
(c) Strobila
(d) All the above.
Answer:
(a) Metameres (somites).

Question 3.
Pharyngeal ganglion in leech is a part of:
(a) Excretory system
(b) Nervous system
(c) Reproductive system
(d) Respiratory system
Answer:
(b) Nervous system

Question 4.
The brain of leech lies above, the _____.
(a) Mouth
(b) Buccal Cavity
(c) Pharynx
(d) Crop.
Answer:
(c) Pharynx

Question 5.
The body of leech has:
(a) 23 segments
(b) 33 segments
(c) 38 segments
(d) 30 segments
Answer:
(b) 33 segments

Question 6.
Mammals are animals.
(a) Cold blooded
(b) Warm blooded
(c) Poikilothermic
(d) All the above
Answer:
(b) Warm blooded

Question 7.
The animals which give birth to young ones are _____.
(a) Oviparous
(b) Viviparous
(c) Ovoviviparous
(d) All the above.
Answer:
(d) All the above

II. Fill in the blanks:

1. The posterior sucker is formed by the fusion of the ………. segments.
2. The existence of two sets of teeth in the life of an animal is called ……….. dentition.
3. The anterior end of leech has a lobe-like structure called ………..
4. The blood sucking habit of leech is known as ………..
5. ………. separate nitrogenous waste from the blood in rabbit.
6. ……… spinal nerves are present in rabbit.

Answer:

1. last seven
2. diphyodont
3. anterior sucker
4. sanguivorous
5. Nephrons (kidney)
6. 37 pair

III. Identify whether the statements are True or False. Correct the false statement:

1. An anticoagulant present in saliva of leech is called heparin.
2. The vas deferens serves to transport the ovum.
3. The rabbit has a third eyelid called tympanic membrane which is movable.
4. Diastema is a gap between premolar and molar teeth in rabbit.
5. The cerebral hemispheres of rabbit are connected by band of nerve tissue called corpora quadrigemina.

Answer:

1. True
2. False – Vas deferens serves to transport the sperm.
3. True
4. False – The gap between the incisors and premolars.
5. False – The cerebral hemispheres of rabbit are connected by band of nerve tissue called corpora corpus callosum.

IV. Match columns I, II and III correctly:

Answer:

V. Answer in a sentence:

Question 1.
Give the common name of the Hirudinaria granulosa.
Answer:
The common name of Hirundinaria granulosa is Indian Cattle Leech.

Question 2.
How does leech respire?
Answer:
Leech respire through the skin.

Question 3.
Write the dental formula of rabbit.
Answer:
The dental formula of rabbit is \(\frac{2033}{1023}\)

Question 4.
How many pairs of testes are present in leech?
Answer:
There are 11 pairs of testes are present in Leech.

Question 5.
How is diastema formed in rabbit?
Answer:
Diastema is due to the absence of canine. It is a gap between incisors and premolars in the upper jaw and lower jaw.

Question 6.
What organs are attached to the two bronchi?
Answer:
The organs attached to the two bronchi are lungs.

Question 7.
Which organ acts as a suction pump in leech?
Answer:
The Pharynx acts as a suction pump in Leech.

Question 8.
What does CNS stand for?
Answer:
The full form of CNS is Central Nervous System.

Question 9.
Why is the teeth of rabbit called heterodont?
Answer:
The dentition of rabbit is called heterodont, as they have different types of teeth (Incisors, premolars and molars).

Question 10.
How does leech suck blood from the host?
Answer:
The Anterior sucker helps in feeding, while both the suckers, help in attachment and locomotion.

VI. Short answer questions:

Question 1.
Why are the rings of cartilages found in trachea of rabbit?
Answer:
The wall of larynx which serves as the voice box is supported by 4 cartilaginous plates. When the air passes the vocal cord, it vibrates resulting in sound production.

Question 2.
List out the parasitic adaptations in the leech.
Answer:
Leeches lead a parasitic mode of life, by sucking the blood of vertebrates. The adaptations are

• Blood is sucked by the pharynx.
• Anterior and Posterior Suckers are provided, by which the animal attaches itself to the body of the host.
• The three Jaws, inside the mouth, causes a painless Y – shaped wound in the skin of the host,
• The salivary glands produce Hirudin, which does not allow the blood to coagulate. So, the continuous supply of blood is maintained.
• Parapodia and Setae are absent.
• Blood is stored in the crop. It gives nourishment to the leech for several months. So there is no elaborate secretion of the digestive juices and enzymes.

VII. Long answer questions:

Question 1.
How is the circulatory system designed in leech to compensate the heart structure?
Answer:
The circulation in Leech is Haemocoelic system. There are no true blood vessels. The blood vessels are replaced by channels called Haemocoelic channels or canals, filled with blood like a fluid. The coelomic fluid contains Haemoglobin.

There are four longitudinal channels. One channel lies above (dorsal) to the Alimentary canal, one below (ventral) to the Alimentary canal. The other two channels lie on either (lateral) side of the Alimentary canal, which serves as a heart and have inner valves. All the four channels are connected together posteriorly in the 26th segment. Thus the circulatory system is designed in Leech to compensate the heart structure.

Question 2.
How does locomotion take place in leech?
Answer:

1. Looping or Crawling movement : Looping movement is brought about by the contraction and relaxation of muscles. The two suckers serve for attachment during movement. The animal fixes its posterior sucker on the substratum.
2. Swimming movement : The animal swims in the water by undulating movements of the body.

Question 3.
Explain the male reproductive system of rabbit with a labelled diagram.
Answer:
The male rabbit has a pair of testes. They are oval in shape. They are kept in two sacs called scrotal sacs hanging down from the abdomen. Each testes is formed of numerous fine tubules called seminiferous tubules. A coiled tubule called epididymis is formed at the end of seminiferous tubules. Epididymis lead into the sperm duct called vas deferens. The vas deferens run forward and enters abdominal cavity through urinary bladder. The urethra runs back and passes into the penis. There are three accessory glands associated with the male reproductive system. They are prostate glands, cowper’s gland and perineal glands. Their secretion nourishes and activates the reproduction.

VIII. Higher Order Thinking Skills (HOTS).

Question 1.
Arjun is studying in the tenth standard. He was down with fever and went to meet the doctor. As he went to the clinic he saw a patient undergoing treatment for severe leech bite. Being curious, Arjun asked the doctor why leech bite was not felt as soon as it attaches to the skin? What would have been the reply given by the doctor?
Answer:
The doctors would have replied that the leeches inject an anaesthetic substance, that prevents the host from feeling their bite.

Question 2.
Shylesh has some pet animals at his home. He has few rabbits too, one day while feeding them he observed something different with the teeth. He asked his grandfather, why is it so? What would have been the explanation of his grandfather?
Answer:
The rabbit has three types of teeth – Incisors are front teeth used for cutting, premolar and molar are used for grinding. Canine is absent as rabbit are herbivores. The gap between the incisor and premolar is called diastema. It helps in mastication and chewing of food in herbivores animal.

IX. Value-Based Questions:

Question 1.
Leeches do not have an elaborate secretion of digestive juices and enzymes. Why?
Answer:
The digestion in leeches in very slow. So, the blood stored in the crop gives nourishment to the leech for several months. So there is not elaborate secretion of digestive juices and enzymes.

Question 2.
How is the digestive system of rabbit suited for herbivorous mode of feeding?
Answer:
Rabbit are herbivores which feed on plants. The plant contain cellulose which need cellulose to digest. The laccum of Rabbit contain large number of symbiotic bacteria that helps in digestion of cellulose.

Samacheer Kalvi 10th Science Structural Organisation of Animals Additional Important Questions and Answers

I. Choose the correct answer:

Question 1.
(a) Vas deferens and Epididymis
(b) Ovary and Caeca
(c) Hirudin and Stomach
(d) Nephridia and Papillae.
Answer:
(a) Vas deferens and Epididymis

Question 2.
Diastema is:
(a) A part of pelvic girdle in rabbit
(b) A type of tooth in rabbit
(c) Space in teeth line in mammals
(d) Structure in eye of rabbit
Answer:
(c) Space in teeth line in mammals

Question 3.
(a) Suckers and Mammary glands
(b) Cowper’s gland and Perineal gland
(c) Forebrain and Oesophagus
(d) Cellulose and Colouration.
Answer:
(b) Cowper’s gland and Perineal gland

Question 4.
If the dental formula of rabbit is \(\frac{2023}{1023}\) What does it show?
(a) Total number of teeth in Rabbit is 15
(b) Number of total incisors in Rabbit is 3
(c) Diastema is present between incisors and premolars
(d) In the formula 2033 is for adult and 1023 is for young ones
Answer:
(c) Diastema is present between incisors and premolars

Question 5.
Number of pairs of salivary glands present in Rabbit is:
(a) one
(b) three
(c) four
(d) five
Answer:
(c) four

Question 6.
Number of Vertebrae in rabbit is:
(a) 44 – 47
(b) 40 – 44
(c) 42 – 48
(d) 47 – 50
Answer:
(a) 44 – 47

Question 7.
If the diaphragm of a rabbit is perforated breathing is:
(a) Not affected
(b) Increased
(c) Decreased
(d) Stopped
Answer:
(d) Stopped

Question 8.
Tracheal rings in rabbit are:
(a) complete
(b) dorsally incomplete
(c) lateral incomplete
(d) incomplete
Answer:
(b) dorsally incomplete

Question 9.
Which one of the following is not a characteristic of leech?
(a) closed circulatory system
(b) segmentation
(c) pseudo coelom
(d) ventral nerve cord
Answer:
(c) pseudo coelom

Question 10.
The blood vascular system, of rabbit is:
(a) open type
(b) closed type
(c) semi closed type
(d) semi open type
Answer:
(b) closed type

Question 11.
The wall of Rabbit’s heart is thick due to the presence of:
(a) Inner layer endocardium
(b) Middle layer myocardium
(c) Outer layer pericardium
(d) Outer layer epicardium
Answer:
(b) Middle layer myocardium

Question 12.
Leech belongs to the class:
(a) polychaeta
(b) oligochaeta
(c) hirundinea
(d) archiannelida
Answer:
(c) hirundinea

Question 13.
A temporary clitellum occur during the breeding season in:
(a) Pheretima
(b) Heteroneris
(c) Hirundinaria
(d) Aphrodile
Answer:
(c) Hirundinaria

Question 14.
Saliva of leeches contains an anti coagulation called:
(a) Heparin
(b) Histamine
(c) Hirudin
(d) Haematin
Answer:
(c) Hirudin

II. Fill in the blanks:

1. Hirudinaria granulosa belong to the phylum ……..
2. The scientific name of the rabbit is ………
3. ………. is the segmentation of the body.
4. The type of movement is brought by the contraction and relaxation of muscles in leeches is ………
5. In leech, the digestion takes place in stomach by the action of …………
6. The ……….. prevents the entry of food into the trachea through the glottis.
7. The existence of two sets of teeth in the life of an animal is called ………… dentition.
8. ……….. contains bacteria that helps in digestion of cellulose.
9. The anterior part of the oviduct in rabbit is …………
10. Breathing movement in mammals are brought by ………..
Answer:
1. Annelida
2. Oryctolagus cuniculus
3. Metamerism
4. Looping or crawling movement
5. Proteolytic enzyme
6. Epiglottis
7. Diphyodont
8. Caecum
9. Fallopian tube
10. Diaphragm

III. Identify whether the statements are True or False. Correct the false statement:

1. Mammary gland in male is the most striking feature of mammals.
2. The leech makes a triradiate or y-shaped incision in the skin of the host by the joins protrude through the mouth.
3. Crop and its diverticular in leech can store large amount of blood which can be slowly digested.
4. Breathing movement in Rabbit are brought by the movement of vibrissae.
5. In rabbit pair of cowper’s gland and perineal gland are present only in the male.

Answer:

1. False – Mammary gland in female is the most striking feature of mammals.
2. True
3. True
4. False – Breathing movement in Rabbit are brought by Diaphragm
5. False – In rabbit pair of cowper’s gland and perineal gland are present both male and female

IV. Match the following:

Answer:
A. (v)
B. (i)
C. (ii)
D. (iii)
E. (iv)

V. Answer in a sentence:

Question 1.
Name the excretory organ of leech.
Answer:
Excretion in leech takes place by nephridia.

Question 2.
Give the Scientific name of Rabbit.
Answer:
Oryctolagus Cuniculus.

Question 3.
Where is the brain of rabbit located?
Answer:
The brain of rabbit is located in the cranial cavity and covered by three membrane of duramater, piamater and arachnoid membrane.

Question 4.
How many pairs of cranial nerves are there in the Peripheral Nervous System?
Answer:
12 pairs of cranial nerves.

Question 5.
What is other name of whiskers in rabbit?
Answer:
The sides of the upper lip produce stiff long thick hairs called vibrissae or whisker which are tactile sensory organ.

Question 6.
Which type of rabbit are endangered species?
Answer:
Pygmy Rabbits are listed as an endangered species.

Question 7.
Name the existence of two sets of teeth in the life of an animal.
Answer:
Diphyodont dentition

Question 8.
Why Rabbits are called gregarious animals?
Answer:
Rabbits are called gregarious animals as they move in group.

Question 9.
Which animals are called sanguivorous?
Answer:
Blood sucking animals.

Question 10.
What are nephridropores?
Answer:
In leech, excretion takes place by segmentally arranged paired tubules called nephridia. There are 17 pairs of nephridia which open by nephridiopores from 6th to 22nd segment.

VI. Short Answer Questions:

Question 1.
Write the systematic position of Indian Cattle Leech.
Answer:

Question 2.
What do you know about the Trunk of Rabbit?
Answer:
The trunk is divisible into an anterior thorax and a posterior abdomen. In females, four or five teats or nipples are present on the ventral surface between Thorax and abdomen. The trunk has two pairs of Pentadactyl limbs. The forelimbs are shorter than the hind limbs.

All the digits bear claws. The anus is present at the posterior end. In females, on the ventral side, a slit-like Vulva is present. In males, the Penis is present in the ventral side of Anus. The male has a pair of testes, enclosed by Scrotal Sacs.

Question 3.
How do the leeches respire?
Answer:
There is no special respiration organ in leech. The skin serves as a respiratory i organ. The capillaries containing the haemocoelomic fluid extend in between the cells of the epidermis, acts as a permeable membrane through which the exchange of gases takes place by diffusion.

Question 4.
What are diphyodont dentition and Heterodont dentition?
Answer:
The existence of two sets of teeth in the life of an animal is called diphyodont dentition. The two types of teeth are Milk teeth (Young ones) and Permanent teeth (in adults).

The different types of dentition are called Heterodont. There are four kinds of teeth in mammals.
The incisors (I), Canines (C), Premolars (PM) and Molars (M).

Question 5.
List out the five layers of body wall of Leech.
Answer:
The body wall of leech consists of five layers.

1. Cuticle
2. Epidermis
3. Dermis
4. Muscular layer and
5. Botryoidal tissue

Question 6.
Give the systematic position of Rabbit.
Answer:

Question 7.
Explain the Respiratory system of Leech.
Answer:
Respiration takes place through the skin in Leech. Dense, network to tiny blood vessels called Capillaries, containing haemocoel fluid extend, in between the cells of the epidermis. The exchange of respiratory gases takes place by diffusion. Oxygen dissolved in water diffuses through the skin, into haemocoel fluid, while Carbon dioxide, diffuses out. The skin is kept moist and slimy, due to the secretion of mucus, which prevents the skin from drying.

Question 8.
List out the steps involved in Inspiration in Rabbit.
Answer:
During Inspiration the atmospheric air takes the following route.

VII. Long answer questions:

Question 1.
Compare the digestive system of Leech and Rabbit.
Answer:

Question 2.
Short notes on the Nervous System of Leech.
Answer:
The Central Nervous System of Leech consists of a nerve ring and a paired ventral nerve cord. The nerve ring surrounds the Pharynx and is formed of Suprapharyngeal ganglion (brain), Circum pharyngeal connective and Subpharyngeal ganglion. The Subpharyngeal ganglion lies below the Pharynx and is formed by the fusion of four pairs of Ganglia.

Students can download 10th Science Chapter 12 Plant Anatomy and Plant Physiology Questions and Answers, Notes, Samacheer Kalvi 10th Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 12 Plant Anatomy and Plant Physiology

Samacheer Kalvi 10th Science Plant Anatomy and Plant Physiology Text Book Back Questions and Answers

I. Choose the correct answer:

Question 1.
Casparian strips are present in of the root.
(a) cortex
(b) pith
(c) pericycle
(d) endodermis
Answer:
(d) endodermis

Question 2.
The endarch condition is the characteristic feature of ______.
(a) root
(b) stem
(c) leaves
(d) flower.
Answer:
(b) stem

Question 3.
The xylem and phloem arranged side by side on same radius is called:
(a) radial
(b) amphivasal
(c) conjoint
(d) None of these
Answer:
(c) conjoint

Question 4.
Which is formed during anaerobic respiration:
(a) Carbohydrate
(b) Ethyl alcohol
(c) Acetyl CoA
(d) Pyruvate
Answer:
(b) Ethyl alcohol

Question 5.
Kreb’s cycle takes place in ______.
(a) chloroplast
(b) mitochondrial matrix
(с) stomata
(d) inner mitochondrial membrane.
Answer:
(b) mitochondrial matrix

Question 6.
Oxygen is produced at what point during photosynthesis?
(a) when ATP is converted to ADP
(b) when CO₂ is fixed
(c) when H₂O is splitted
(d) All of these
Answer:
(d) All of these

II. Fill in the blanks:

1. Cortex lies between ……….
2. Xylem and phloem occur on the same radius constitute a vascular bundle called ………..
3. Glycolysis takes place in ………..
4. The source of O₂ liberated in photosynthesis is ……….
5. …….. is the ATP factory of the cells.

Answer:

1. epidermis and Pericycle
2. conjoint bundles
3. cytoplasm
4. splitting of Water molecules
5. Mitochondria

III. State whether the statements are true or false. Correct the false statement.

1. Phloem tissue is involved in the transport of water in plants.
2. The waxy protective covering of a plant is called as the cuticle.
3. In monocot, stem cambium is present in between xylem and phloem.
4. Palisade parenchyma cells occur below the upper epidermis in the dicot root.
5. Mesophyll contains chlorophyll.
6. Anaerobic respiration produces more ATP than aerobic respiration.

Answer:

1. False – Phloem tissue is involved in the transport of food in plants.
2. True
3. False – In monocot stem cambium is absent.
4. True
5. True
6. False – Aerobic respiration produces more ATP than anaerobic respiration.

IV. Match the following:

Answer:
A. (iii)
B. (iv)
C. (i)
D. (v)
E. (ii)

V. Answer in a sentence:

Question 1.
What is the collateral vascular bundle?
Answer:
If xylem and phloem in a vascular bundle are arranged along the same radius with phloem towards the outside, such vascular bundle is called a collateral vascular bundle.

Question 2.
Where does the carbon that is used in photosynthesis come from?
Answer:
The carbon that is used in photosynthesis comes from CO₂ from the air.

Question 3.
What is the common step in aerobic and anaerobic pathway?
Answer:
Glycolysis is the common step in aerobic and anaerobic respiration.

Question 4.
Name the phenomenon by which carbohydrates are oxidized to release ethyl alcohol.
Answer:
Alcohol fermentation.

VI. Short answer questions:

Question 1.
Give an account on vascular bundle of dicot stem.
Answer:
Vascular bundles of dicot stem are conjoint (xylem and phloem lies in the same radius) collateral (xylem is the centre and phloem lies towards periphery) endarch (proto xylem in the centre, Meta xylem lies in the periphery) and open (cambium present in between xylem and phloem: They are arranged in the form of ring around the pith.

Question 2.
Write a short note on mesophyll.
Answer:
In Dicot leaf, the tissue present between the upper and lower epidermis is called mesophyll. It is differentiated into

1. Palisade Parenchyma: They are found below the epidermis and are elongated. They have a number of chloroplasts and can take part in photosynthesis. The cells do not have intercellular spaces.
2. Spongy Parenchyma: They are found below the palisade parenchyma tissue. Cells are spherical or oval and are irregularly arranged. Cells have intercellular spaces and help in gaseous exchange.

In monocot leaves, mesophyll is present between both upper and lower epidermal layer. The cells are irregularly arranged with intercellular spaces. Mesophyll cells contain chloroplasts, to take part in photosynthesis.

Question 3.
Draw and label the structure of oxysomes.
Answer:

Question 4.
Name the three basic – tissues systems in flowering plants.
Answer:
The three basic tissue system in flowering plants are:

• Dermal or epidermal tissue system.
• Ground tissue system.
• Vascular tissue system.

Question 5.
What is photosynthesis and where in a cell does it occur?
Answer:
Photosynthesis is a process by which autotrophic organisms (green plants, algae and chlorophyll containing bacteria) utilize the energy from sunlight to synthesize their own food. It occur in the chloroplast of the cell.

Question 6.
What is respiratory quotient?
Answer:
Respiratory quotient is the ratio of volume of carbon dioxide liberated and the volume of oxygen consumed during respiration. It is expressed as

Question 7.
Why should the light – dependent reaction occur before the light-independent reaction?
Answer:
In light – dependent photosynthesis, the photosynthetic pigment absorbs the light energy and convert it into chemical energy, ATP and NADPH₂. These products move out from grana to the stroma of the chloroplast for the light-independent reactions (Dark reaction or Biosynthetic pathway). During this reaction, CO₂ is reduced in the carbohydrates with the help of light generated ATP and NADPH₂. So the light-dependent reaction should occur before the light-independent reaction.

Question 8.
Write the reaction for photosynthesis.
Answer:
The overall reaction for photosynthesis.

VII. Long Answer Questions:

Question 1.
Differentiate the following:
(a) Monocot root and Dicot root
Answer:

(b) Aerobic and Anaerobic respiration
Answer:

Question 2.
Describe and name three stages of cellular respiration that aerobic organisms use to obtain energy from glucose.
Answer:
The name and the three stages of cellular respiration.

• Glycolysis: (Glucose splitting): Glycolysis is the break down of one molecule of Glucose (6 Carbon) into two molecules of Pyruvic acid (3 Carbon). It takes place in the cytoplasm of the cell.
• Kreb’s cycle: This cycle occurs in the mitochondria matrix. At the end of Glycolysis, 2 molecules of pyruvic acid enter into mitochondria. The oxidation of pyruvic acid into CO₂ and H₂O takes place through this cycle. It is also called as Tricarboxylic Acid Cycle. (TCA)
• Electron transport chain: It is a system of Electron Transport Chain (ETC) located on the inner membrane of the mitochondria. NADH₂ and FADH₂ molecules formed during Glycolysis and Krebs cycle are oxidised to NAD+ and FAD+ to release the energy via electrons.

The electrons, as they move through the system, release energy which is trapped by ADP to synthesize ATP. This is called Oxidative Phosphorylation. During this process, oxygen which is the acceptor of electrons gets reduced to water.

Question 3.
How does the light dependent reaction differ from the light independent reaction?
What are the end product and reactants in each? Where does each reaction occur within the chioroplast?
Answer:

VIII. Higher Order Thinking Skills(HOTS):

Question 1.
The reactions of photosynthesis make up a biochemical pathway.
(a) What are the reactants and products for both light and dark reactions.
Answer:
The reaction of photosynthesis can be grouped into two: Light and Dark reaction.
The reaction involving pigments, solar energy and water that produce ATP and NADPH₂ are called light reaction.
The photosynthetic reactions in which CO₂ is reduced to carbohydrates making use of ATP and NADPH₂ generated by light reaction are called dark reaction.
The overall reaction of photosynthesis can be written as follows:

(b) Explain how the biochemical pathway of photosynthesis recycles many of its own reactions and identify the recycled reactants.
Answer:
Light reaction use light to synthesize ATP and NADPH₂. The calvin cycle uses these reactants to produce sugar from CO₂ molecule.
This cycle then produce NAP + ADP + Pi which is used in light reaction with H₂O molecules to produce ATP and NADPH₂ again.

Question 2.
Where do the light-dependent reaction and the Calvin cycle occur in the chloroplast?
Answer:
The Light-dependent reaction occurs in the Thylakoid membranes (Grana) of the chloroplast. The Light independent reaction occurs in the stroma of the chloroplast.

Samacheer Kalvi 10th Science Plant Anatomy and Plant Physiology Additional Important Questions and Answers

I. Choose the correct answer:

Question 1.
The root hairs originate from:
(a) trichoblast
(b) endodermis
(c) hypodermis
(d) pericycle
Answer:
(a) trichoblast

Question 2.
Sachs classified tissue system in plants into _____.
(a) five types
(b) two types
(c) three types
(d) four types.
Answer:
(c) three types

Question 3.
The innermost layer of the cortex is:
(a) epidermis
(b) hypodermis
(c) endodermis
(d) pericycle
Answer:
(c) endodermis

Question 4.
The powerhouse of the cell or ATP factory of the cells _____.
(a) Plastids
(b) Vacuoles
(c) Nucleus
(d) Mitochondria.
Answer:
(d) Mitochondria.

Question 5.
The vascular bundle with protoxylem facing centre of the stem is:
(a) exarch
(b) endarch
(c) tetrarch
(d) polyarch
Answer:
(b) endarch

Question 6.
This is the first step of both Aerobic and Anaerobic respiration _____.
(a) Electron transport chain
(b) Respiratory Quotient
(c) Glycolysis
(d) Kreb’s Cycle.
Answer:
(c) Glycolysis

Question 7.
The vascular bundle in the leaf is:
(a) collateral and open
(b) collateral and closed
(c) bicollateral and open
(d) collateral and exarch
Answer:
(b) collateral and closed

Question 8.
Photosynthesis takes place in:
(a) mitochondria
(b) peroxisomes
(c) chloroplast
(d) ribosomes
Answer:
(c) chloroplast

Question 9.
The dark reaction of photosynthesis were discovered by:
(a) Embden and Meyer
(b) Melvin and Calvin
(c) Kreb
(d) Pamas
Answer:
(b) Melvin and Calvin

Question 10.
………. is the organelle of cell respiration.
(a) mitochondria
(b) chloroplast
(c) plastids
(d) cell wall
Answer:
(a) mitochondria

Question 11.
The hypodermis of monocot stem consists of:
(a) Collenchyma
(b) Sclsrenchyma
(c) Angular collenchyma
(d) Parenchyma
Answer:
(b) Sclsrenchyma

Question 12.
The layer is morphologically homologous to the endodermis found in the root which is:.
(a) periderm
(b) epidermis
(c) starch sheath
(d) mesophyll tissue
Answer:
(c) starch sheath

Question 13.
Pericycle is absent in:
(a) dicot stem
(b) monocot root
(c) dicot root
(d) monocot stem
Answer:
(d) monocot stem

Question 14.
………. is not a characteristic feature of spongy parenchyma.
(a) Gaseous exchange
(b) Photosynthesis
(c) Irregular
(d) Closely arranged
Answer:
(d) Closely arranged

Question 15.
Which of the following is not applicable of dicot stem?
(a) wedge shaped
(b) endarch
(c) collateral
(d) closed
Answer:
(d) Closely arranged

II. Application based question:

Question 1.
In the given flow chart different layer of monocot root is shown. What is A and B?

(a) A – Hypodermis, B – Vascular bundle
(b) A – Cortex, B – Vascular bundle
(c) A – Cortex, B – Xylem
(d) A – Hypodermis, B – Xylem
Answer:
(b) A – Cortex, B – Vascular bundle

Question 2.
Casparian strip are characteristic feature of A endodermis and it is made up of B. What is A and B respectively?
(a) shoot, suberin
(b) root, lignin
(c) root, suberin
(d) root and shoot, suberin
Answer:
(c) root, suberin

Question 3.
Which of the following is present in monocot leaves?
A. Bulliform cell
B. Leaf base
C. Bundle sheath
D. Resin gland
E. Water cavity
(a) A, B, C, E
(b) A, B, D, E
(c) A, B, E
(d) A, B, C
Answer:
(d) A, B, C

Question 4.
A vascular bundle in which phloem is on both the sides of the xylem and separated from it by strips of cambium is said to be:
(a) Collateral open
(b) Bicollateral open
(c) Concentric
(d) Bicollateral closed
Answer:
(b) Bicollateral open

Question 5.
Presence of cuticle is a common character of:
A. Monocot stem
B. Dicot stem
C. Monocot root
D. Dicot root
E. Monocot leaf
F. Dicot leaf
(a) A, B, E, F
(b) B, F
(c) A, B, C, D, E, F
(d) A, E, F
Answer:
(a) A, B, E, F

III. Fill in the blanks:

1. ………. is known as “Father of Plant Anatomy”.
2. ……….. are the group of cells that are similar or dissimilar in structure and origin, but perform similar function.
3. Based on the ability to divide, tissues are classified into ……….. and ……… tissue.
4. ………. is the outermost layer.
5. The main function of vascular tissue system are transport of ……….. and ……….
6. Epidermis protects the ……… tissue.
7. ………, ………., ………… and ……….. forms the ground tissue system.
8. Epiblema is also known as ……… or ……….
9. ……….. helps in the movement of water and dissolved salts from cortex into xylem.
10. The tissue present between xylem and phloem is called …………
11. All the tissues inner to endodermis constitute …………
12. The tissue present between the upper and lower epidermis is called …………
13. Reaction centres and the accessory pigments together are called …………
14. Light reaction takes place in ………. membrane of the chloroplast.
15. Kreb cycle is also known as ……….
16. Glycolysis take place in ……… of the cell.
17. Krebs cycle occurs in ……….. matrix.
18. The gas evolved during photosynthesis is ……….
19. The first step in aerobic respiration is ………..
20. Energy currency of cells is ………..
21. Major functions of epiblema is ……….
Answer:
1. Nehemiah Grew
2. Tissues
3. Meristamatic and Permanent
4. Epidermis
5. Water and Food
6. inner
7. Cortex, Endodermis, Pericycle and Pith
8. Rhizodermis or Piliferous layer
9. Casparian strips
10. Conjuctive tissue
11. Stele
12. Hypodermis
13. Photosystems
14. thylakoid
15. Tricarboxylic Acid Cycle (TCA)
16. Cytoplasm
17. Mitochondria
18. Oxygen
19. Glycolysis
20. ATP
21. Protection

IV. Match the following:

Answer:
A. (iv)
B. (iii)
C. (i)
D. (v)
E. (ii)

V. Answer in Sentence:

Question 1.
What are the functions of Epidermis?
Answer:

• The epidermis protects the inner surface.
• Stomata help in transpiration.
• Root hairs help in absorption of water and minerals.

Question 2.
Name the factors which affect photosynthesis.
Answer:
The process of photosynthesis is affected internally by:

1. Pigments
2. Leaf age
3. Accumulation of carbohydrates and
4. Hormones.

The process of photosynthesis is affected externally by:

1. Light
2. CO₂
3. Temperature
4. Water
5. Minerals.

Question 3.
What are Oxysomes?
Answer:
The inner mitochondria membrane bear minute regularly spaced, Tennis racket shaped particles called Oxysomes, which involve in ATP synthesis.

Question 4.
What is Cortex?
Answer:
The region below the epidermis is called cortex. Its main function is to store starch.

Question 5.
What is Pericycle?
Answer:
Pericycle is the outer most layer of stele. It is made of single layer of thin walled cells.

Question 6.
What are the functions of chloroplasts?
Answer:

• Photosynthesis
• Storage of starch
• Synthesis of fatty acids
• Storage of lipids
• Formation of chloroplasts.

Question 7.
Where are passage cell located and write its function?
Answer:
The passage cell is an endodermal cell located opposite to the protoxylem, which are thin wall without casparian strips. The main function of passage cell is entry of water from cortex to xylem.

Question 8.
What is protoxylem lacuna?
Answer:
In mature vascular bundle the lowest proto xylem disintegrates and form a cavity called protoxylem lacuna. Eg: Monocot stem.

Question 9.
Define Kreb’s cycle.
Answer:
The series of cyclic reaction involved in converting pyruvic acid to CO₂ and water in mitochondria is called Kreb’s cycle.

Question 10.
Why mitochondria is called ‘Power house of the cell’?
Answer:
A large number of ATP molecules are produced in the mitochondria, so they are called power house of the cell.

VI. Short answer questions:

Question 1.
Name the three types of plastids.
Answer:

1. Chloroplast: green coloured plastids helps in photosynthesis.
2. Chromoplast: yellow, red, orange coloured plastids, gives colour to flowers and fruits.
3. Leucoplast: colourless plastids, store food.

Question 2.
List out the functions of chloroplast.
Answer:

1. Photosynthesis
2. Storage of starch
3. Synthesis of fatty acids
4. Storage of lipids

Question 3.
What are Concentric bundles? Explain its types.
Answer:
Vascular bundles in which either xylem completely surrounds the phloem or phloem surrounds the xylem is called concentric vascular bundle. It is of two types:

1. Amphivasal: Xylem surrounds phloem. Eg: Dracaena
2. Amphicribral: Phloem surrounds xylem. Eg: Ferns

Question 4.
What are photosynthetic pigment?
Answer:

1. Pigments involved in photosynthesis are called Photosynthetic pigments.
2.  Primary pigment traps solar energy and converts it into electrical and chemical energy. Accessory pigments pass on the absorbed energy to primary pigment.

Question 5.
(a) Differentiate between Palisade parenchyma and spongy parenchyma.
Answer:

(b) Differentiate between Monocot ieaf and Dicot leaf.
Answer:

Question 6.
Define stele.
Answer:
Central Part inner to endodermis is called stele. It includes pericycle and vascular system.

Question 7.
Where respiratory cavity is located?
Answer:
The air space that is found next to the stomata is called respiratory cavity or sub stomatal cavity.

Question 8.
What is an isobilateral leaf? Give an example.
Answer:
In monocot leaf, the mesophyll is not differentiated into palisade parenchyma and spongy parenchyma (i.e., made of only spongy or palisade parenchyma) is called isobilateral leaf.
Eg: Grass (Monocot leaf)

Question 9.
What is dorsiventral leaf? Give an example.
Answer:
In dicot leaf, the mesophyll is differentiated into palisade parenchyma on the upper side and spongy parenchyma on the lower side. A leaf showing this differentiation is mesophyll is designated as dorsiventral. Eg: Dicot leaf.

Question 10.
Define tetrarch xylem.
Answer:
If the number of proto xylem points are four, the xylem is called tetrarch. Eg: Dicot root

Question 11.
What are generally called as accessory pigments?
Answer:
Photosynthetic pigments other than chlorophyll ‘a’ are generally I called accessory pigments. Eg: Chlorophyll ‘A’- Carotenoids and Xanthophyll.

Question 12.
W’rite any three significance of photosynthesis.
Answer:

1. It is the source of all our food and fuel,
2. It drives all other process of biological and a biological world,
3. It is responsible for the growth and sustenance of our biosphere.

Question 13.
What are the functions of epidermal tissue system?
Answer:

1. Epidermis protects the inner tissues.
2. Stomata helps in transpiration.
3. Root hairs help in absorption of water and minerals.

Question 14.
Differentiate between monocot and dicot stem.
Answer:

VII. Long answer questions:

Question 1.
Explain Epidermal tissue system.
Answer:

1. The outer most covering layer of plants.
2. It contains epidermis, stomata and epidermal out growths.
3. Epidermis are interrupted by many minute pores called stomata.
4. Epidermis is covered by cuticle to check evaporation of water.
5. Trichomes and root hairs are some epidermal growths.

Question 2.
Explain the types of Vascular bundle.
Answer:
Xylem and Phloem are present in the form of bundles called vascular bundles.
1. Radial
2. Conjoint
3. Concentric.
1. Radial vascular bundle : Xylem and phloem are arranged in an alternate matter or different radii are called Radial vascular bundle. Eg: roots

2. Conjoint vascular bundle : Xylem and phloem are arranged in the same radius are called conjoint vascular bundle. Divided in two types:
(a) Collateral vascular bundles : Xylem and phloem are arranged in the same radius with phloem towards the outside is called collateral vascular bundles. Eg: stem and leaf.
Collateral vascular bundles are of two types:

• Open collateral vascular bundle: Vascular bundle consists of cambial tissue in between xylem and phloem are called Open collateral vascular bundle. Eg: Dicot stem
• Closed collateral vascular bundle: Cambium is absent in vascular bundle are called Closed collateral vascular bundle. Eg: Monocot stem.

(b) Bicollateral : Phloem occurs on both the outer and inner side of xylem. This vascular bundle is Bicollateral vascular bundle. Eg: Cucurbita.

3. Concentric vascular bundle : The vascular bundle in which either phloem surrounds the xylem or xylem surrounds the phloem completely called Concentric vascular bundles. It is of two types: (a) Amphivasal, (b) Amphicribral.
(a) Amphivasal: The Xylem completely surrounds the phloem. Eg: Dracaena
(b) Amphicribral: The Phloem completely surrounds the xylem. Eg: Ferns

Exarch: Protoxylem vessels are present towards the periphery and meta xylem towards the centre. Eg: Root
Endarch: Protoxylem are present towards the centre and meta xylem towards the periphery. Eg: Stem

Question 3.
Explain the Primary structure of Monocot root.
Answer:
The internal structure of Monocot root has
1. Epiblema/Rhizodermis
2. Cortex
3. Endodermis
4. Stele
1. Epiblema/Rhizodermis:

• Outer most layer of monocot root.
• Made up of single layer of thin walled, paranchymatous cell.
• Root hair helps in absorption of water and minerals.
• Stomata and cuticle are absent.
• Main function is to protect inner tissue.

2. Cortex:

• The region below the epidermis is cortex.
• Made up of only parenchymatous cells with intercellular space.
• It is a multi layer.
• Function is to store water and food material.

3. Endodermis:

• Inner most cortex is called Endodermis.
• It forms a complete ring around the stele with characteristic Casparian strips and Passage cell.
• There is a band like thickening made of suberin in casparian strips.

(iv) Stele:
Central part inner to endodermis is stele.
It contains Pericycle, vascular bundles and pith.
(a) Pericycle:

• Outer most layer of stele made of single layer of tightly arranged Parenchymatous cell.
• Function is to originate lateral root.

(b) Vascular bundles:

• Radial arrangement of vascular tissue.
• Xylem is exarch and polyarch.
• The conjuctive tissue is sclerenchymatous tissue.

(c) Pith:

• Large central part, composed of parenchyma cells with intercellular spaces.
• Function is to store the starch.

Question 4.
Draw the structure of Dicot root.
Answer:

Question 5.
Describe the Primary structure of T.S of Monocot stem.
Answer:
(i) Epidermis:

• Outer most layer of monocot stem.
• Made up of single layer and tightly packed parenchyma cells.
• Outer wall is covered by thick cuticle.
• Few stomata are seen in epidermis.
• Multicellular hairs are absent.

(ii) Hvpodermis:

• The layer below the epidermis is called hypodermis.
• Hypodermis is made up of sclerenchymatous cells.
• It is interrupted by chlorenchyma.

Sclerenchyma provides mechanical support to plant.

(iii) Ground tissue:

• There is no distinction of cortex, endodermis, pericycle and pith.
• Inner to hypodermis parenchyma cell forms the ground tissue.

(iv) Vascular bundles:

• Vascular bundles are scattered in the ground tissue. Each vascular bundle are surrounded by bundle sheath by sclerenchymatous tissue.
• Vascular bundles are conjoint, collateral, endarch and closed.
• Xylem contains meta xylem and protoxylem.
• In mature Vascular bundle the lowest protoxylem disintegrates and form a cavity called protoxylem lacuna.
• Phloem contains seive tubes and companion cells.

(v) Pith:

• It is not differentiated in monocot stem.

Question 6.
Write a short note on structure of chloroplast.
Answer:
(i) Chloroplast are the actual site of photosynthesis.
(ii) They are green plastids containing green pigment called chlorophyll.
(iii) It mainly consists of Envelope, Stroma, Thylakoids and Grana.

Envelope : Chloroplast has outer and inner envelope membranes which is seperated by intermembrane space.
Stroma : Matrix present inside to the membrane is called stroma. It contains DNA, 70 S ribosomes and other molecules required for protein synthesis.
Thylakoids : It’s membrane encloses thylakoid lumen. Thylakoids forms a stack of disc like structures called a grana (singular-granum).
Grana : Some of the thylakoids are arranged in the form of discs stacked one above the other. These stacks are termed as grana,they are interconnected to each other by membranous lamellae called Fret channels.

Question 7.
Explain the primary structure of T.S Dicot stem.
Answer:
The internal structure of Dicot stem has
(i) Epidermis :

• Outer most layer of dicot stem made up of tightly packed parenchyma cells.
• Outer wall is covered by thick cuticle which check transpiration.
• Few stomata and multicellular hairs are present in epidermal cells.

(ii) Cortex :
Cortex is differentiated into 3 zones:

• Hypodermis : The layer below the epidermis is called Hypodermis. It is made by few layers of collenchymatous cells which gives mechanical strength.
• Middle cortex : Inner to hypodermis is made up of few layer of chlorenchymatous tissue which helps in photosynthesis.
• Inner cortex : Inner cortex is made by parenchyma cells which stores food materials. The inner most layer of cortex is called endodermis. The cells are compactly arranged in barrel shaped cells that contain starch grains. So this layer also called starch sheath.

(iii) Stele :
Central part inner to endodermis is called stele. It contains pericycle, vascular bundle and pith.

• Pericycle : A few layer of sclerenchyma cells occurs in patches outside the phloem in each vascular bundle.
• Vascular bundle : Vascular bundle are conjoint collateral, endarch and open. They are arranged in the form of ring.
• Pith : Large central part, composed if parenchyma cells with intercellular spaces. Function is to store the food.

Question 8.
Describe the structure of T.S of dicot leaf.
Answer:
The T.S of dicot leaf contains
(i) Epidermis – Upper and Lower
(ii) Mesophyll
(iii) Vascular bundles

(i) Epidermis :
The leaf is dorsiventral it has upper and lower epidermis.

• Upper Epidermis : Made up of single layer of tightly packed parenchyma cells. Cuticle is thicker than the lower epidermis.
• Lower Epidermis : Made up of single layer of parenchymatous cells with thin cuticle. Stomata are more in Lower epidermis. Used for transpiration and gaseous exchange.

(ii) Mesophyll :
The region between upper and lower epidermis is called mesophyll. It is differentiated into palisade and spongy parenchyma.

• Palisade parenchyma: Present below the upper epidermis cells are elongated. Cells do not have intercellular spaces. More number of chloroplast present. Function is photosynthesis.
• Spongy parenchyma: Present above the lower epidermis. Cells are irregular shaped. Cells have intercellular spaces less number of chloroplast is present. Function is gaseous exchange.

(iii) Vascular bundles : Vascular bundles are conjoint, collateral and closed. Vascular bundles are surrounded by a compact layer of parenchymatous cells. These are called Bundle sheath. Xylem is present towards the upper epidermis. Phloem is present towards the lower epidermis.

VIII. Higher Order Thinking Skills (HOT).

Question 1.
The cells of endodermis show band like thickening on their radial and inner tangential walls called casparian strips. Why?
Answer:
It is to prevent the re-entry of water into the cortex once water entered the xylem tissue.

Question 2.
Do plants like Croton, with non – green leaves have chlorophyll and do they perform photosynthesis?
Answer:
The chlorophyll is present in Croton leaves, embedded along with other coloured pigments like carotenoids and anthocyanin. These coloured pigments assist or help the pigment chlorophyll in the process of photosynthesis.

Question 3.
How do we see beautiful colours in Autumn and enjoy the fall?
Answer:
Chlorophyll gives a green colour to plants. During winter, there is not enough light for photosynthesis. So they use food, which is stored in summer. As the green chlorophyll disappears or fades away, we begin to see yellow, orange and red colour. We cannot see them in summer, because they are covered by the green chlorophyll.

But in autumn or fall season glucose trapped in the leaves, after photosynthesis stops. Sunlight and cool nights of autumn cause the leaves to turn this glucose into a red colour.
It is the combination of all these things, that make the beautiful colours, we enjoy in the fall.

Students can download 10th Social Science Geography Chapter 4 Resources and Industries Questions and Answers, Notes, Samacheer Kalvi 10th Social Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Social Science Solutions Geography Chapter 4 Resources and Industries

Samacheer Kalvi 10th Social Science Resources and Industries Text Book Back Questions and Answers

I. Choose the correct answer

Question 1.
Manganese is used in:
(a) Storage batteries
(b) Steel Making
(c) Copper smelting
(d) Petroleum Refining
Answer:
(b) Steel Making

Question 2.
The Anthracite coal has
(a) 80 to 95% Carbon
(b) Above 70% Carbon
(c) 60 to 7% Carbon
(d) Below 50% Carbon
Answer:
(a) 80 to 95% Carbon

Question 3.
The most important constituents of petroleum are hydrogen and:
(a) Oxygen
(b) Water
(c) Carbon
(d) Nitrogen
Answer:
(c) Carbon

Question 4.
The city which is called the Manchester of South India is
(a) Chennai
(b) Salem
(c) Madurai
(d) Coimbatore
Answer:
(d) Coimbatore

Question 5.
The first Jute mill of India was established at:
(a) Kolkata
(b) Mumbai
(c) Ahmedabad
(d) Baroda
Answer:
(a) Kolkata

Question 6.
The first Nuclear Power station was commissioned in
(a) Gujarat
(b) Rajasthan
(c) Maharashtra
(d) Tamil Nadu
Answer:
(c) Maharashtra

Question 7.
The most abundant source of energy is:
(a) Biomass
(b) Sun
(c) Coal
(d) Oil
Answer:
(b) Sun

Question 8.
The famous Sindri Fertilizer Plant is located in
(a) Jharkhand
(b) Bihar
(c) Rajasthan
(d) Assam
Answer:
(a) Jharkhand

Question 9.
The nucleus for the development of the chotanagpur plateau region is:
(a) Transport
(b) Mineral Deposits
(c) Large demand
(d) Power Availability
Answer:
(b) Mineral Deposits

Question 10.
One of the shore-based steel plants of India is located at
(a) Kolkata
(b) Tuticorin
(c) Goa
(d) Visakhapatnam
Answer:
(d) Visakhapatnam

II. Match the following

Question 1.
Match the Column I with Column II.

Answer:
A. (ii)
B. (i)
C. (iv)
D. (v)
E. (iii)

Question 2.
Match the Column I with Column II.

Answer:
A. (v)
B. (iv)
C. (i)
D. (ii)
E. (iii)

III. Answer the following questions briefly

Question 1.
Define the resource and state its types.
Answer:
Any matter or energy derived from the environment that is used by living things including humans is called a natural resource.
Types of Natural Resources are:

1. Renewable and
2. Non – renewable resources.

Question 2.
Name the states that lead in the production of Iron ore in India.
Answer:
Jharkhand is the leading producer of Iron ore (25%), other states are Odisha (21%), Chattisgarh (18%), Karnataka (20%), Andhra Pradesh (5%) and also the state of Tamil Nadu.

Question 3.
What are the minerals and its types?
Answer:
A mineral is a natural substance of organic or inorganic origin with definite chemical and physical properties.
Types of Minerals are:

1. Metallic minerals
2. Non – metallic minerals.

Question 4.
State the uses of Manganese.
Answer:

1. Manganese is a silvery grey element always available with iron, laterite and other minerals.
2. It is very hard and brittle. So it is used for making iron and steel to give strength.
3. It also serves as raw materials for alloying.
4. It is also used in the manufacture of bleaching powder, insecticides, paints and batteries.

Question 5.
What is natural gas?
Answer:
It usually accompanies petroleum accumulations.
[OR]
Natural gas is an important clean energy resources found in association with or without petroleum. It is used as a source of energy as well as an industrial raw material in the petrochemical industry. It is considered an eco-friendly fuel because of low carbondioxide emissions.

Question 6.
Name the different types of coal with their carbon content.
Answer:
Based on carbon content coal is classified into

1. Anthracite – contains 80% to 90% carbon.
2. Bituminous – contains 60% to 80% carbon.
3. Lignite – contains 40% to 60% carbon
4. Peat – less than 40% carbon

Question 7.
Mention the major areas of jute production in India.
Answer:
West Bengal, Andhra Pradesh, Bihar, Uttar Pradesh, Assam, Chattisgarh, Odisha are the major jute producing area.

Question 8.
Name the important oil producing regions of India.
Answer:
West coast: Mumbai high, Gujarat coast, Basseim, Aliabet (South of Bhavanagar), Ankleshwar, Cambay – Luni region, Ahmedabad -Kaloi region and Punjab – Haryana.

East Coast: Brahmaputra valley, Digboi, Nahoratitya, Moran-Hugrijan, Rudrasagar-Lawa (Assam region), Surrma Valley. Andaman and Nicobar, Gulf of Mannar, Punjab. Haryana, Baleshwar coast.

IV. Distinguish between

Question 1.
Renewable and non-renewable resources
Answer:
Renewable resources:

1. These resources can be replenished after utilization.
2. Abundantly available in nature.
3. Eg: Sun energy, Wind etc.

Non-Renewable resources:

1. These resources cannot be regained after utilization.
2. Limited stock take millions of years for formation.
3. Eg: Minerals

Question 2.
Metallic and non-metallic minerals
Answer:
Metallic minerals:

1. These minerals contain one or more metallic elements.
2. They can be further classified into ferrous and Non-ferrous minerals.
3. Eg: Iron-ore, Manganese

Non-Metallic minerals:

1. These minerals do not contain metal in them.
2. They can be classified into energy fuels and construction minerals.
3. Eg: Coal, Petroleum, lime stone, Gypsum.

Question 3.
Agra based industry and mineral based industry.
Answer:
Agro based industry:

1. These industries obtain raw materials from agricultural products.
2. Eg: Cotton textile industry, Jute mills, Silk industry, Sugar industry etc.
3. Labour intensive

Mineral based industry:

1. These industries obtain raw materials from metallic and non- metallic minerals.
2. Eg: Coal industry, Iron and Steel industry etc.
3. Capital intensive

Question 4.
Jute industry and sugar industry.
Answer:
Jute industry:

1. Second largest textile industry.
2. Jute fibre is the basic raw material.
3. Gunny bags, Canvas, pack sheets,Cordage are some of the Jute products.
4. Concentrated in and around West Bengal.

Sugar industry:

1. Second largest agro based industry.
2. Sugarcane is the basic raw material.
3. Sugar Jaggery, Khandsari are some of the products of sugar industry.
4. Uttar Pradesh have more than 50% of the sugar industries.

Question 5.
Conventional energy and non- conventional energy
Answer:
Conventional energy:

1. Non renewable energy.
2. Mainly energy is produced by burning fossil fuels.
3. Production of energy till the stock of mineral availability.
4. Thermal power – Coal, petroleum and Natural gas and Nuclear minerals.

Non-Conventional energy:

1. Renewable energy
2. Mainly energy is produced by harnessing power from nature.
3. Continuous flow of energy production is possible.
4. Solar energy, Wind energy. Bio mass energy, tidal and wave energy.

V. Answer the following in a paragraph

Question 1.
Write about the distribution of cotton textile industries in India.
Answer:
The cotton textile industries contribute about 7% of industrial output, 2% of India’s GDP and 15% of the country’s export earnings. It is one of the largest sources of employment generation in the country. At present there are 1,719 textile mills in the country. Out of which 188 mills are in public sector, 147 in cooperative sector and 1,284 in private sector. Currently, India is the third largest producer of cotton and has the largest loom arc and ring spindles in the world. At present, cotton textile industry is the largest organized modem industry of India. About 16% of the industrial capital, 14% of industrial production and over 20% of the industrial labour of the country are engaged in this industry.

The higher concentration of textile mills in and around Mumbai, makes it as “Manchester of India”. Presence of black cotton soil in Maharashtra, humid climate, presence of Mumbai port, availability of hydro power, good market and well developed transport facility favour the cotton textile industries in Mumbai. The major cotton textile industries are concentrated in the states of Maharashtra, Gujarat, West Bengal, Uttar Pradesh and Tamil nadu. Coimbatore is the most important centre in Tamil nadu with 200 mills out of its 435 and called as “Manchester ‘ of South India”. Erode, Tirupur, Karur, Chennai, Thirunelveli, Madurai, Thoothukudi, Salem and Virudhunagar are the other major cotton textiles centres in the state.

Question 2.
Explain the factors responsible for the concentration of jute industries in the Hoogly region.
Answer:
The following factors are responsible for the concentration of Jute industries in the Hoogly region in West Bengal.

1. Raw materials: West Bengal is the largest producer of Jute. Availability of raw Jute for production.
2. Processing: Jute require fresh water for processing. Abundant water supply is available by the riverines and continuous supply of fresh water is ensured due to Perennial nature.
3. Transport: Well connected by the network of water ways, road ways and railways.
4. Cheap labour: West Bengal is one of the densely populated area . So cheap labour is available.
5. Market: Kolkatta being one of the textile centre great demand for the product as well as port facilities available for export.

Question 3.
Write an account on the major iron and steel industries of India.
Answer:
Iron and Steel industry is the basic industry. The raw materials are obtained both from Metallic and Non-Metallic minerals.

Iron and Steel industries are located in close proximity to the coal fields or Iron ore mines.

VI. On the outline map of India mark the following.

Question 1.
iron ore production centres.
Answer:

Question 2.
Centres of Petroleum and Natural Gas production.
Answer:

Question 3.
Coal mining centres.
Answer:

Question 4.
Areas of cultivation of cotton.
Answer:

Question 5.
Iron and Steel industries.
Answer:

Samacheer Kalvi 10th Social Science Resources and Industries Additional Important Questions and Answers

I. Choose the correct answer

Question 1.
The ………………. is called as mineral oil.
(a) Petroleum
(b) Coal
(c) Natural gas
(d) Mica
Answer:
(a) Petroleum

Question 2.
Manchester of India is ……..
(a) Delhi
(b) Mumbai
(c) Chennai
Answer:
(b) Mumbai

Question 3.
The ………………. is the largest oil field in India producing 65% of oil.
(a) Ankaleshwar
(b) Mumbai high
(c) Kalol
(d) Surma valley
Answer:
(b) Mumbai high

Question 4.
Chotta Nagpur plateau is noted for ……..
(a) Natural vegetation
(b) Mineral resource
(c) Cotton cultivation
Answer:
(b) Mineral resource

Question 5.
TamilNadu produces about ………………. % of the total thermal electricity produced in India.
(a) 5
(b) 20
(c) 18
(d) 90
Answer:
(a) 5

Question 6.
In India most of the Iron and Steel industries are located in the …… plateau.
(a) Chott Nagpur
(b) Deccan
(c) Malwa
Answer:
(a) Chott Nagpur

Question 7.
Areas near ………………. district has the largest concentrations of wind farm capacity at a single location in the world.
(a) Ramanathapuram
(b) Tuticorin
(c) Thiruvallur
(d) Kanyakumari
Answer:
(d) Kanyakumari

Question 8.
The resources that can be reproduced again and again is called ……
(a) Mineral resources
(b) Renewable resource
(c) Natural resource
Answer:
(b) Renewable resource

Question 9.
Bysinosis is an occupational lung disease caused by exposure to:
(a) natural gas
(b) cotton dust
(c) coal power
(d) automobile
Answer:
(b) cotton dust

Question 10.
Lignite is extracted in Tamil Nadu …….
(a) Kadaloor
(b) Neyveli
(c) Madurai
Answer:
(b) Neyveli

Question 11.
National News Print and Papermills (NEPA) is in ………………. state.
(a) Odisha
(b) West Bengal
(c) TamilNadu
(d) Madhya Pradesh
Answer:
(d) Madhya Pradesh

Question 12.
Sugar bowl of India is …….
(a) West Bengal
(b) Uttar pradesh and Bihar
(c) Mumbai
Answer:
(b) Uttar pradesh and Bihar

Question 13.
The ………………. is the largest producer of electronic goods in India.
(a) Bengaluru
(b) Mysuru
(c) Delhi
(d) Jaipur
Answer:
(a) Bengaluru

Question 14.
The leading producer of electronic goods is ……..
(a) Bangalore
(b) Coimbatore
(c) Hyderabad
Answer:
(a) Bangalore

Question 15.
………………. is an aluminium ore.
(a) Manganese
(b) Magnesium
(c) Bauxite
(d) Anthracite
Answer:
(c) Bauxite

II. Match the following

Question 1.
Match the Column I with Column II.

Answer:
A. (iv)
B. (iii)
C. (i)
D. (v)
E. (ii)

Question 2.
Match the Column I with Column II.

Answer:
A. (iii)
B. (v)
C. (ii)
D. (i)
E. (iv)

Question 3.
Match the Column I with Column II.

Answer:
A. (iii)
B. (iv)
C. (v)
D. (ii)
E. (i)

III. Answer the following questions briefly

Question 1.
What are the features of copper and aluminium?
Answer:

• Malleability
• Expandability
• Good conductor of heat and energy (electricity)

Question 2.
Where was the first hydro-electric power station in India established?
Answer:
The first hydro-electric power station in India was established at “Darjeeling” in 1897.

Question 3.
In which type of rocks is limestone found?
Answer:
Limestone is found in sedimentary rocks.

Question 4.
What is the origin of the word petroleum?
Answer:
The word petroleum is derived from two Latin words petro (Rock) and Oleum (oil) thus petroleum is oil obtained from rocks of the earth. It is also called as mineral oil.

Question 5.
Name any five software centres.
Answer:

1. Chennai
2. Bangalore
3. Mysore
4. Hyderabad
5. Coimbatore

Question 6.
When was the Nuclear power programme initiated in India and where was the first Atomic Power station was set up?
Answer:

1. Nuclear Power programme was initiated in the 1940s, when “ Tata Atomic Research Commission was incorporated in August 1948.
2. The 1st nuclear power station was set up at Tarapur near Mumbai in 1969.

Question 7.
What are the raw materials for the paper industry?
Answer:
Woodpulp, bamboo, salai, Sabai grasses, waste paper and bagasse

Question 8.
Write a note on NPCIL.
Answer:

1. The Nuclear Power Corporation of India Limited ( NPCIL) is wholly owned by the Government of India.
2. It is a Public sector undertaking.
3. Responsible for the generation of nuclear power for electricity.
4. Administered by the Department of Atomic Energy (DAE). It is responsible for designing, constructing and operating the Nuclear power stations in India.

Question 9.
What are the major centres of the automobile industry?
Answer:
Mumbai, Chennai, Kolkata, New Delhi, Pune, Ahmedabad, Lucknow, Satara and Mysore.

Question 10.
Where are the centres of IT parks located in India?
Answer:
Centres of IT parks in India are located in Chennai, Coimbatore, Thiruvananthapuram, Bengaluru, Mysuru, Hyderabad, Vishakapatnam, Mumbai, Pune, Indore, Gandhinagar, Jaipur, Noida, Mohali and Srinagar.

IV. Distinguish between

Question 1.
Paper industry and Iron and Steel industry.
Answer:
Paper industry

1. Forest-based industry.
2. Serve as an index for education and literacy.
3. Wood pulp, Bamboo, bagasse are some of the basic raw materials.

Iron and Steel industry:

1. Mineral-based industry.
2. Key industry for industrial development.
3. Iron ore and Manganese are the main raw materials.

Question 2.
Solar and Wind energy.
Answer:
Solar energy:

1. Conversion of sunlight into electricity.
2. Photo voltoic cells or use of lenses, mirror and tracking system is used.
3. Installation cost is more and different applications is required as per the need.
4. Occupy more space.

Wind energy:

1. Conversion of energy is from the flow of wind.
2. Wind turbines are used.
3. Installation cost is comparatively less.
4. Occupy less space.

Question 3.
Difference between Manganese and Mica.
Answer:
Manganese:

1. It is a Metallic mineral.
2. Very hard and brittle in nature.
3. Raw material for iron and steel basic raw material for alloying.

Mica:

1. It is a Non-Metallic mineral.
2. Translucent, splitable into thin sheets, elastic and incompressible.
3. Exclusively used in electrical goods and also for making lubricants, paints, varnishes etc.

Question 4.
Iron and Steel industry and Software industry.
Answer:
Iron and Steel industry:

1. Age old industry.
2. Depend upon minerals.
3. Large scale industry.
4. Began in 1907.

Software industry:

1. Recently developed industry.
2. Depend upon skill and knowledge (technical).
3. Small and medium scale industry.
4. Began in 1970.

V. Answer the following in a paragraph

Question 1.
Enumerate the automobile industry as the fast-growing industry of India.
Answer:
The first automobile industry was established at the Premier Automobiles Ltd at Kurla (Mumbai) in 1947 and the Hindustan Motor Ltd at Uttarpara (Kolkata) in 1948. At present India is the 7th largest producer of automobile manufactures which includes two wheelers, commercial vehicles, passenger cars, Jeep, scooty, scooters, motor cycles mopeds and three wheelers.

Among the production of two wheelers, motorcycles are manufactured at Faridabad, Haryana and Mysore. While scooters are manufactured at Lucknow, Satara, Akudi (Pune), Panki (Kanpur) and Odhai (Ahmedabad). The cars produced at Haryana, Kolkata, Mumbai and Chennai are Maruti, Ambassador, Fiat, Ford and Hyndai etc. Presenceof foreign car companies such as Mercedes Benz, Fiat, General Motors, Toyota and the recent entry of passenger cars manufacturers BMW, Audi, Volks Wagen and Volvo makes the Indian automobile sector a special one.

Several new joint venture agreements for the manufacture of cars have recently been signed by the Indian companies and renowned car manufacturers of the world. The Indian auto industry is said to take a big leep in the near fixture. This expected to provide much more competitive environment to the industry and a wide choice of ultra modem cars to the consumers. This is the fast growing industry in India.

Question 2.
What are the different forms of Iron ore and their nature?
Answer:
Iron ores are rocks and minerals from which metallic iron can be economically extracted.

The different forms of Iron ore are:

Form of Iron ores	Iron content %
Magnetite	72.4%
Haemetite	69.9%
Goethite	62.9%
Limonite	55%
Siderite	48.2%

Nature: The ores are usually rich in iron oxides and vary in colour from dark grey, bright yellow or deep purple to rusty red.

Question 3.
Write about the uses of Coal and its areas of distribution.
Answer:

1. Coal is a non-renewable resource. It is available in the form of sedimentary rocks.
2. It has close association with the industrial development of any country.

Uses: Coal is an important source of energy in India with its varied and innumerable uses

1. It is converted into gas, oil and thermal power electricity.
2. Besides it forms a basic raw materials for the production of chemicals, dyes, fertilizers, paints, synthetic and explosives.
3. Distribution: Indian coal is mostly associated with Gondwana region and is primarily found in peninsular India.
4. The States of Jharkhand, Odisha, West Bengal and Madhya Pradesh alone account for nearly 90% of coal reserves of the country. About 2% of India’s coal is of tertiary type and is mostly in Assam and Jammu and Kashmir.
5. Jharkhand is the largest coal producing state in the country. Indian lignite (brown coal) deposits occur particularly in Tamil Nadu ( Neyveli), Puducherry and Kerala.

Question 4.
Give an account on Automobile industry in India.
Answer:
Automobile industry’ is one of the most dynamic industrial groups in India. India is the 7th largest producer of automobile manufacturers.

Distribution: The automobile industries are found in four clusters viz: Delhi, Gurgaon and Manesar in North India.

West India: Pune, Nasik, Halol and Aurangabad East India: Jamshedpur and Kolkatta South India: Chennai, Bengaluru and Hosur.

Major-Indian companies which manufacture commercial vehicles: Tata motors, Ashok Leyland, Mahindra and Mahindra, Eicher motors and Ford motors.

Foreign companies which manufacture commercial vehicles: Hyundai, Mercedes Benz , ITEC, MAN.

Automobile industries in India manufactures two wheelers passenger car, Jeep, Scooty, Scooter, Mopeds, Motorcycles and three wheelers.

Passenger car manufacturers: Tata motors, Maruti Suzuki , Mahindra and Mahindra and Hindustan motors are Indian companies.

Foreign car companies in India: Mercedez Benz, Fiat, General motors, Toyota, recent entry BMW, Audi, Volkswagon and Volvo.

Two wheeler manufacturing is dominated by Indian companies like Hero, Bajaj Auto and TVS.

Major centres of Automobile industries: Mumbai, Chennai, Jamshedpur, Jabalpur, Kolkata, Pune, New Delhi, Kanpur, Bengaluru, Satara, Lucknow • and Mysuru. Chennai is named as “Detroit of Asia” due to the presence of major automobile manufacturing units and allied industries around the city.

Question 5.
What are the major challenges faced by the Indian industries?
Answer:
Some major challenges faced by industries in India are:

1. Non-availability of large blocks of land.
2. Shortage and fluctuation in power supply.
3. Non-availability of cheap labourers.
4. Poor access to credit.
5. High rate of interest for borrowed loan.
6. Lack of technical and vocational training for employees.
7. In appropriate living conditions nearby industrial areas.

VI. On the outline map of India mark the following

Question 1.
Any two places producing limestone
Answer:

Question 2.
Any two Nuclear power stations
Answer:

Question 3.
Any two Thermal power stations in Tamil Nadu
Answer:

Question 4.
Wind farm places (any 2)
Answer:

Students can Download Tamil Nadu 12th Physics Model Question Paper 4 English Medium Pdf, Tamil Nadu 12th Physics Model Question Papers helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

TN State Board 12th Physics Model Question Paper 4 English Medium

General Instructions:

• The question paper comprises of four parts.
• You are to attempt all the parts. An internal choice of questions is provided wherever applicable.
• All questions of Part I, II, III, and IV are to be attempted separately.
• Question numbers 1 to 15 in Part I are Multiple Choice Questions of one mark each.
  These are to be answered by choosing the most suitable answer from the given four
  alternatives and writing the option code and the corresponding answer
• Question numbers 16 to 24 in Part II are two-mark questions. These are to be answered
  in about one or two sentences.
• Question numbers 25 to 33 in Part III are three-mark questions. These are to be answered
  in about three to five short sentences.
• Question numbers 34 to 38 in Part IV are five-mark questions. These are to be answered
  in detaiL Draw diagrams wherever necessary.

Time: 3 Hours
Max Marks: 70

Part – I

Answer all the questions. Choose the correct answer. [15 x 1 = 15]

Question 1.
Which charge configuration produces a uniform electric field?
(a) point charge
(b) infinite uniform line charge
(c) uniformly charged infinite plane
(d) uniformly charged spherical shell
Answer:
(c) uniformly charged infinite plane

Question 2.
The work done in carrying a charge Q, once round a circle of radius R with a charge Q₂ at the centre is  ………….
(a) \(\frac{\mathrm{Q}_{1} \mathrm{Q}_{2}}{4 \pi \varepsilon_{0} \mathrm{R}^{2}}\)
(b) Zero
(c)  \(\frac{\mathrm{Q}_{1} \mathrm{Q}_{2}}{4 \pi \varepsilon_{0} \mathrm{R}} \)
(d) infinite
Answer:
(b) Zero
Hint: The electric field is conservative. Therefore, no work is done in moving a charge around a closed path in a electric field.

Question 3.
The internal resistance of a 2.1 V cell which gives a current of 0.2 A through a resistance of 10 Ω is……………………..
(a) 0.2 Ω
(b) 0.5 Ω
(c) 0.8 Ω
(d) 1.0 Ω
Answer:
(b) 0.5 Ω

Question 4.
An electron moves straight inside a charged parallel plate capacitor of uniform charge density σ. The time taken by the electron to cross the parallel plate capacitor when the plates of the capacitor are kept under constant magnetic field of induction \(\overrightarrow{\mathrm{B}}\) is ……….


Answer:
(d)

Question 5.
In a series resonant RLC circuit, the voltage across 100Ω resistor is 40 V. The resonant frequency co is 250 rad/s. If the value of C is 4 pF, then the voltage across L is……………….
(a) 600 V
(b) 4000 V
(c) 400 V
(d) IV
Answer:
(c) 400 V

Question 6.
During the propagation of electromagnetic waves in a medium:
(a) electric energy density is double of the magnetic energy density
(b) electric energy density is half of the magnetic energy density
(c) electric energy density is equal to the magnetic energy density
(d) both electric and magnetic energy densities are zero
Answer:
(c) electric energy density is equal to the magnetic energy density

Question 7.
First diffraction minimum due to a single slit of width 1.0 x 10^-5 cm is at 30°. Then wavelength of light used is, …………………
(a) 400 Å
(b) 500 Å
(c) 600 Å
(d) 700 Å
Answer:
(b) 500 Å
Hint. For diffraction minima, d sin θ = nλ
\(\lambda=\frac{d \sin \theta}{n}=\frac{1 \times 10^{-5} \times 10^{-2} \times \sin 30^{\circ}}{1}=0.5 \times 10^{-7}\)
λ = 500 Å

Question 8.
The sky would appear red instead of blue if
(a) atmospheric particles scatter blue light more than red light
(b) atmospheric particles scatter all colours equally
(c) atmospheric particle scatter red light more than blue light
(d) the sun was much hotter
Answer:
(c) atmospheric particle scatter red light more than blue light

Question 9.
Kinetic energy of emitted electron depends upon
(a) frequency
(b) intensity
(c) nature of atmosphere surrounding the electron
(d) none of these
Answer:
(a) frequency
Hint: Kinetic energy of emitted electron depends on the frequency of incident radiation.

Question 10.
The ratio between the first three orbits of hydrogen atom is…………….
(a) 1:2:3
(b) 2:4:6
(c) 1:4:9
(d) 1:3:5
Answer:
(c) 1:4:9
Hint :
E_n = \(\frac{-13.6 \times z^{2}}{n^{2}}\)
n = 1; E₁ =- 13.6 eV/ atom
n = 2; E₂ = – 3.4 eV/ atom
n = 3; E₃ = -1.51 eV/atom                             ’
The ratio of three orbits E₁ : E₂ : E₃ = 13.6 : 3.4 : 1.51 = 1 : 4 : 9

Question 11.
Bohr’s theory of hydrogen atom did not explain fully
(a) diameter of H-atom
(b) emission spectra
(c) ionisation energy
(d) the fine structure of even hydrogen spectrum
Answer:
(d) the fine structure of even hydrogen spectrum
Hint: Bohr theory could not explain the five structure of hydrogen spectrum.

Question 12.
If a half-wave rectified voltage is fed to a load resistor, which part of a cycle the load current will flow?
(a) 0° – 90°
(b) 90° – 180°
(c) 0° – 180°
(d) 0° – 360°
Answer:
(c) 0° – 180°

Question 13.
Diamond is very hard because ……………..
(a) it is covalent solid
(b) it has large cohesive energy
(c) high melting point
(d) insoluble in all solvents
Answer:
(b) it has large cohesive energy

Question 14.
The internationally accepted frequency deviation for the purpose of FM broadcasts.
(a) 75 kHz
(b) 68 kHz
(c) 80 kHz
(d) 70 kHz
Answer:
(a) 75 kHz

Question 15.
The blue print for making ultra durable synthetic material is mimicked from
(a) Lotus leaf
(b) Morpho butterfly
(c) Parrot fish
(d) Peacock feather
Answer:
(c) Parrot fish

Part – II

Answer any six questions in which Q. No 17 is compulsory.   [6 x 2 = 12]

Question 16.
Define ‘electric flux’.
Answer:
The number of electric field lines crossing a given area kept normal to the electric field lines  is called electric flux. Its unit is N m² C^-1. Electric flux is a scalar quantity.

Question 17.
Determine the number of electrons flowing per second through a conductor, when a current of 32 A flows through it.
Answer:
I = 32A, t= 1 s
Charge of an electron, e = 1.6 x 10^-19 C
The number of electrons flowing per second, n =?

Question 18.
Define magnetic flux.
Answer:
The number of magnetic field lines crossing per unit area is called magnetic flux φ_B
\(\phi_{\mathrm{B}}=\overrightarrow{\mathrm{B}} \cdot\overrightarrow{\mathrm{A}}=\mathrm{B} \mathrm{A} \cos \theta=\mathrm{B} \perp \mathrm{A}\)

Question 19.
Give any one definition of power factor.
Answer:
The power factor is defined as the ratio of true power to the apparent power of an a.c. circuit.
It is equal to the cosine of the phase angle between current and voltage in the a.c. circuit.

Question 20.
State the laws of reflection.
Answer:

• The incident ray, reflected ray and normal to the reflecting surface all are coplanar (ie. lie in the same plane).
• The angle of incidence i is equal to the angle of reflection r. i = r

Question 21.
Why do metals have a large number of free electrons?
Answer:
In metals, the electrons in the outer most shells are loosely bound to the nucleus. Even at room temperature, there are a large number of free electrons which are moving inside the metal in a random manner.

Question 22.
The radius of the 5th orbit of hydrogen atom is 13.25 A. Calculate the wavelength of the electron in the 5th orbit.
Answer:
2πr = nλ
2 x 3.14 x 13.25 Å = 5 x λ
.’. λ = 16.64 Å

Question 23.
Draw the output waveform of a full wave rectifier.
Answer:

Question 24.
Explain centre frequency or resting frequency in frequency modulation.
Answer:
When the frequency of the baseband signal is zero (no input signal), there is no change in the frequency of the carrier wave. It is at its normal frequency and is called as centre frequency or resting frequency.

Part – III

Answer any six questions in which Q.No. 28 is compulsory. [6 x 3 = 18]

Question 25.
What is corona discharge?
Answer:
The electric field near the edge is very high and it ionizes the surrounding air. The positive ions are repelled at the sharp edge and negative ions are attracted towards the sharper edge.
This reduces the total charge of the conductor near the sharp edge. This is called action at points or corona discharge.

Question 26.
What is electric power and electric energy?
Answer:
Electric power: It is the rate at which an electric appliance converts electric energy into other forms of energy. Or, it is the rate at which work is done by a source of emf in maintaining an electric current through a circuit.
\({ P }=\frac { { W } }{ t } ={ VI }={ I }^{ 2 }{ R }=\frac { { V }^{ 2 } }{ { R } } \)
Electric energy: It is the total workdone in maintaining an electric current in an electric circuit for a given time.
W = Vt = VIr joule = I²R? joule.

Question 27.
A bar magnet having a magnetic moment \(\overrightarrow{\mathrm{M}}\) is cut into four pieces i.e., first cut in two pieces along the axis of the magnet and each piece is further cut into two pieces. Compute the magnetic moment of each piece.
Answer:
Consider a bar magnet of magnetic moment \(\overrightarrow{\mathrm{M}}\). When a bar magnet first cut in two pieces along the axis, their magnetic moment is \(\frac{\overrightarrow{\mathrm{M}}}{2}\)

Question 28.
The current in an inductive circuit is given by 0.3 sin (200t – 40°) A. Write the equation for the voltage across it if the inductance is 40 mH.
Answer:
L = 40 x 10^-3H; i = 0.1 sin (200 t – 40°); X_L = ωL = 200 x 40 x 10^-3 = 8 Ω
V_m = I_m X_L = 0.3 x 8 = 2.4 V
In an inductive circuit, the voltage leads the current by 90° Therefore,
υ = V_m sin (ωt + 90°)
υ = 2.4 sin (200f – 40°+ 90°)
υ = 2.4 sin (200f +50°)volt

Question 29.
Writedown the integral form of modified Ampere’s circuital law.
Answer:
This law relates the magnetic field around any closed path to the conduction current and displacement current through that path.

Question 30.
Two light sources have intensity of light as I_o. What is the resultant intensity at a point where the two light waves have a phase difference of π/3?
Answer:
Let the intensities be I_o
The resultant intensity is, I = 4 I_o cos² (φ/2)
Resultant intensity when, ϕ = π/ 3, is I = 4I₀ cos² (π / 6) I
= 4I₀(√3 / 2)² =3I₀

Question 31.
Write the properties of cathode rays.
Answer:

• Cathode rays possess energy and momentum and travel in a straight line with high speed of the order of 10⁷m s^-1
• It can be deflected by application of electric and magnetic fields.
• When the cathode rays are allowed to fall on matter, they produce heat.
• They affect the photographic plates and also produce fluorescence when they fall on   certain crystals and minerals.
• When the cathode rays fall on a material of high atomic weight, x-rays are produced.
• Cathode rays ionize the gas through which they pass.
• The speed of cathode rays is up \(\left( \frac { 1 }{ 10 } \right) ^{ th }\) of the speed of light.

Question 32.
Distinguish between wireline and wireless communication.
Answer:

Wireline communication	Wireless communication
It is a point-to-point communication.	It is a broadcast mode communication.
It uses mediums like wires, cable and optical fibres.	It uses free space as a communication medium.
These systems cannot be used for long distance transmission as they are connected.	These systems can be used for long distance transmission.
Ex. telephone, intercom and cable TV.	Ex. mobile, radio or TV broadcasting and satellite communication.

Question 33.
What is the difference between Nano materials and Bulk materials?
Answer:

• The solids are made up of particles. Each of the particle has a definite number of atoms, which might differ from material to material. If the particle of a solid is of size less than 100 nm, it is said to be a ‘nano solid’.
• When the particle size exceeds 100 nm, it is a ‘bulk solid’. It is to be noted that nano and bulk solids may be of the same chemical composition.
• For example, ZnO can be both in bulk and nano form.
• Though chemical composition is the; same, nano form of the material shows strikingly different properties when compared to its bulk counterpart.

Part – IV

Answer all the questions.  [5 x 5 = 25]

Question 34.
(a) Calculate the electric field due to a dipole on its equatorial plane.
Answer:
Electric field due to an electric dipole at a point on the equatorial plane. Consider a point C at a distance r from the midpoint O of the dipole on the equatorial plane as shown in Figure.

Since the point C is equi­distant from +q and -q, the magnitude of the electric fields of +q and -q are the same. The direction of \(\overrightarrow{\mathrm{E}}_{+}\) is along BC \(\overrightarrow{\mathrm{E}}_{-} \) and the direction of E is along CA. \(\overrightarrow{\mathrm{E}}_{+} \) and \(\overrightarrow{\mathrm{E}}_{-} \) and E are resolved into two components; one component parallel to the dipole axis and the other perpendicular to it. The perpendicular components \(\left|\overrightarrow{\mathrm{E}}_{+}\right| \sin \theta \) and \(\left|\overrightarrow{\mathrm{E}}_{-}\right| \sin \theta \) are oppositely directed and cancel each other. The magnitude of the total electric field at point C is the sum of the parallel components of E₊ and E and its direction is \(\overrightarrow { { E } } _{ + }\quad and\quad \overrightarrow { { E } } _{ – }\) and its direction is along \(-\hat{p}\)

(b) How the emf of two cells are compared using potentiometer?
Answer:
Comparison of emf of two cells with a potentiometer: To compare the emf of two cells, the circuit connections are made as shown in figure. Potentiometer wire CD is connected to a battery Bf and a key K in series. This is the primary circuit. The end C of the wire is connected to the terminal M of a DPDT (Double Pole Double Throw) switch and the other terminal N is connected to a jockey through a galvanometer G and a high resistance HR. The cells whose emf ξ₁ and ξ₂ and to be compared are connected to the terminals M₁, N₁ and M₂, N₂, of the DPDT switch. The positive terminals of Bf ξ₁ and ξ₂ should be connected to the same end C.

The DPDT switch is pressed towards M₁, N₁ so that cell ξ₁, is included in the secondary circuit and the balancing length l₁, is found by adjusting the jockey for zero deflection. Then the second cells ξ₂, is included in the circuit and the balancing length l₂, is determined. Let r be the resistance per unit length of the potentiometer wire and I be the current flowing through the wire.
we have
ξ₁ = Irl₁ ……………….. (1)
ξ₂ = Irl₂ ……………….. (2)
By dividing equation (1) by (2)
\(\frac{\xi_{1}}{\xi_{2}}=\frac{l_{1}}{l_{2}}\)
By including a rheostat (Rh) in the primary circuit, the experiment can be repeated several times by changing the current flowing through it.

Question 35.
(a) Discuss the working of cyclotron in detail.
Answer:
Cyclotron : Cyclotron is a device used accelerate the charged particles to gain large kinetic energy. It is also called as high energy accelerator. It was invented by Lawrence and Livingston in 1934.

Principle : When a charged particle moves normal to the magnetic field, it experiences magnetic Lorentz force.

Construction : The particles are allowed to move in between two semicircular metal containers called Dees (hollow D – shaped objects). Dees are enclosed in an evacuated chamber and it is kept in a region with uniform magnetic field controlled by an electromagnet. The direction of magnetic field is normal to the plane of the are enclosed in an evacuated chamber and it is kept in a region with uniform magnetic field controlled by an electromagnet. The direction of magnetic field is normal to the plane of the Dees. The two Dees are kept separated with a gap and the source S (which ejects the particle to be accelerated) is placed at the center in the gap between the Dees. Dees are connected to high frequency alternating potential difference.

Working: Let us assume that the ion ejected from source S is positively charged. As soon as ion is ejected, it is accelerated towards a Dee (say, Dee – 1) which has negative potential at that time. Since the magnetic field is normal to the plane of the Dees, the ion undergoes circular path. After one semi-circular path in Dee-1, the ion reaches the gap between Dees. At this time, the polarities of the Dees are reversed so that the ion is now accelerated towards Dee-2 with a greater velocity. For this circular motion, the centripetal force of the charged particle q is provided by Lorentz force.

\(\frac { mv^{ 2 } }{ r } =qv{ B }\Rightarrow r=\frac { m }{ q{ B } } v\Rightarrow r\propto v\)
From the equation, the increase in velocity increases the radius of circular path. This process continues and hence the particle undergoes spiral path of increasing radius. Once it reaches near the Very important condition in cyclotron operation is the resonance condition. It happens when the frequency { at which the positive ion circulates in the magnetic field must be equal to the constant frequency of the electrical oscillator f_osc From equation
\(f_{\text {osc }}=\frac{q \mathrm{B}}{2 \pi m} \Rightarrow \mathrm{T}=\frac{1}{f_{\text {osc }}}\)
The time Period of oscillation is \(\mathrm{T}=\frac{2 \pi m}{q \mathrm{B}}\)
The kinetic energy of the charged particle is \(\mathrm{KE}=\frac{1}{2} m v^{2}=\frac{q^{2} \mathrm{B}^{2} r^{2}}{2 m}\)

Limitations of cyclotron

• the speed of the ion is limited
• electron cannot be accelerated
• uncharged particles cannot be accelerated

[OR]

(b) Give the uses of Foucault current.
Answer:
Though the production of eddy current is undesirable in some cases, it is useful in some other cases. A few of them are

(1) Induction stove : Induction stove is used to cook the food quickly and safely with less energy consumption. Below the cooking zone, there is a tightly wound coil of insulated wire. The cooking pan made of suitable material, is placed over the cooking zone. When the stove is switched on, an alternating current flowing in the coil produces high frequency alternating magnetic field which induces very strong eddy currents in the cooking pan. The eddy currents in the pan produce so much of heat due to Joule heating which is used to cook the food.

(2) Eddy current brake : This eddy current braking system is generally used in high speed trains and roller coasters. Strong electromagnets are fixed just above the rails. To stop the train, electromagnets are switched on. The magnetic field of these magnets induces eddy currents in the rails which oppose or resist the movement of the train. This is Eddy current linear brake.

In some cases, the circular disc, connected to the wheel of the train through a common shaft, is made to rotate in between the poles of an electromagnet. When there is a relative motion between the disc and the magnet, eddy currents are induced in the disc which stop the train. This is Eddy current circular brake.

(3) Eddy current testing : It is one of the simple non-destructive testing methods to find defects like surface cracks and air bubbles present in a specimen. A coil of insulated wire is given an alternating electric current so that it produces an alternating magnetic field. When this coil is brought near the test surface, eddy current is induced in the test surface. The presence of defects causes the change in phase and amplitude of the eddy current that can be detected by some other means. In this way, the defects present in the specimen are identified.

(4) Electro magnetic damping : The armature of the galvanometer coil is wound on a soft iron cylinder. Once the armature is deflected, the relative motion between the soft iron cylinder and the radial magnetic field induces eddy current in the cylinder. The damping force due to the flow of eddy current brings the armature to rest immediately and then galvanometer shows a steady deflection. This is called electromagnetic damping.

Question 36.
(a) Write down the properties of electromagnetic waves.
Answer:
Properties of electromagnetic waves:

• Electromagnetic waves are produced by any accelerated charge.
• Electromagnetic waves do not require any medium for propagation. So electromagnetic wave is a non-mechanical wave.
• Electromagnetic waves are transverse in nature. This means that the oscillating electric field vector, oscillating magnetic field vector and propagation vector (gives direction of propagation) are mutually perpendicular to each other.
• Electromagnetic waves travel with speed which is equal to the speed of light in vacuum
  or free space, \(c=\frac { 1 }{ \sqrt { \varepsilon _{ 0 }\mu _{ 0 } } } =3\times 10^{ 8 }{ ms }^{ -1 }\)
• The speed of electromagnetic wave is less than speed in free space or vacuum, that is, v < c. In a medium of refractive index,

[OR]

(b) Explain the Young’s double slit experimental setup and obtain the equation for path difference.
Answer:
Experimental setup
Wavefronts from S₁ and S₂ spread out and overlapping takes place to the right side of double slit. When a screen is placed at a distance of about 1 meter from the slits, alternate bright and dark fringes which are equally spaced appear on the screen. These are called interference fringes or bands.

S₁ and S₂ travel equal distances and arrive in-phase. These two waves constructively interfere and bright fringe is observed at O. This is called central bright fringe.

The fringes disappear and there is uniform illumination on the screen when one of the slits is covered. This shows clearly that the bands are due to interference.

Equation for path difference
Let d be the distance between the double slits S₁ and S₂ which act as coherent sources of wavelength λ. A screen is placed parallel to the double slit at a distance D from it. The mid-point of S₁ and S₂ is C and the midpoint of the screen O is equidistant from S₁ and S₂. P is any point at a distance y  from O.

The waves from S₁ and S₂ meet at P either inphase or out-of-phase depending upon the path difference between the two waves. The path difference S between the light waves from S₁ and S₂ to the point P is, δ = S₂P and S₁P
A perpendicular is dropped from the point S₁, to the line S₂P at M to find the path difference more precisely.
δ = S₂P – MP = S₂M
The angular position of the point P from C is θ. ∠OCP = θ.
From the geometry, the angles ∠OCP and ∠S₂S₁ M are equal.
∠OCP = ∠S₂S₁ M = θ
In right angle triangle ΔS₁S₂M, the path difference, S₂M = d sin θ
δ = d sin θ
If the angle θ is small, sin θ ≈ tan θ ≈ θ From the right angle triangle ΔOCP, tan θ = y/D. The path difference, δ =dy/D

Question  37.
(a) Give the construction and working of photo emissive cell.
Answer:
Photo emissive cell:
Its working depends on the electron emission from a metal cathode due to irradiation of light or other radiations.

• It consists of an evacuated glass or quartz bulb in which two metallic electrodes – that is, a cathode and an anode are fixed.
• The cathode C is semi-cylindrical in shape and is coated with a photo sensitive material. The anode A is a thin rod or wire kept along the axis of the semi-cylindrical cathode.
• A potential difference is applied between the anode and the cathode through a galvanometer G.

Working:

• When cathode is illuminated, electrons are emitted from it. These electrons are attracted by anode and hence a current is produced which is measured by the galvanometer
• For a given cathode, the magnitude of
  the current depends on the intensity to incident radiation and
  the potential difference between anode and cathode.

[OR]

Question 37.
(b) Explain the J.J. Thomson experiment to determine the specific charge of electron.
Answer:
In 1887, J. J. Thomson made remarkable improvement in the scope of study of gases in discharge tubes. In the presence of electric and magnetic fields, the cathode rays are deflected. By the variation of electric and magnetic fields, mass normalized charge or the specific charge (charge per unit mass) of the cathode rays is measured.

A highly evacuated discharge tube is used and cathode rays (electron beam) produced at cathode are attracted towards anode disc A. Anode disc is made with pin hole in order to allow only a narrow beam of cathode rays. These cathode rays are now allowed to pass through the parallel metal plates, maintained at high voltage. Further, this gas discharge tube is kept in between pole pieces of magnet such that both electric and magnetic fields are perpendicular to each other. When the cathode rays strike the screen, they produce scintillation and hence bright spot is observed. This is achieved by coating the screen with zinc sulphide.

(i) Determination of velocity of cathode rays
For a fixed electric field between the plates, the magnetic field is adjusted such that the cathode rays (electron beam) strike at the original position O. This means that the magnitude of electric force is balanced by the magnitude of force due to magnetic field. Let e be the charge of the cathode rays, then eE = eBv
\(v=\frac{E}{B}\) …………….. (1)

(ii) Determination of specific charge
Since the cathode rays (electron beam) are accelerated from cathode to anode, the potential energy of the electron beam at the cathode is converted into kinetic energy of the electron beam at the anode. Let V be the potential difference between anode and cathode, then the potential energy is eV. Then from law of conservation of energy,
\(e \mathrm{V}=\frac{1}{2} m v^{2} \Rightarrow \frac{e}{m}=\frac{v^{2}}{2 \mathrm{V}}\)
Substituting the value of velocity from equation (1) , we get
\(\frac{e}{m}=\frac{1}{2 \mathrm{V}} \frac{\mathrm{E}^{2}}{\mathrm{B}^{2}}\) ………..(2)
Substituting the value of E ,B and V, the specific charge vam be determined as
\(\frac{e}{m}=1.7 \times 10^{11} \mathrm{Ckg}^{-1}\)

(iii) Deflection of charge only due to uniform electric field
When the magnetic field is turned off, the deflection is only due to electric field. The
deflection in vertical direction is due to the electric force.
F_e = eE ………………….. (3)
Let m be the mass of the electron and by applying Newton’s second law of motion,
acceleration of the electron is
\(a_{e}=\frac{1}{m} \mathrm{F}_{e}\) ………………… (4)
Substituting equation (4) in equation (3),
\(a_{e}=\frac{1}{m} e E=\frac{e}{m} E\)
Let y be the deviation produced from original position on the screen. Let the initial upward velocity of cathode ray be μ = 0 before entering the parallel electric plates. Let l be the time taken by the cathode rays to travel in electric field. Let l be the length of one of the plates, then the time taken is
\(t=\frac{l}{v}\) …………(5)

Hence, the deflection y’ of cathod rays is( note : u = 0 and \(a_{e}=\frac{e}{m} \mathrm{E}\))

Therefore, the deflection y on the screen is
y α y’ ⇒ y = Cy’
where C is proportionality constant which depends on the geometry of the discharge tube and substituting y’ value in equation (6), we get

Substituting the values on RHS, the value of specific charge is calculated as
e/m = 1.7 x 10¹¹Ckg^-1

Question 38.
(a) What is an LED? Give the principle of operation with a diagram.
Answer:
Light Emitting Diode (LED): LED is a p-n junction diode which emits visible or invisible light when it is forward biased. Since, electrical energy is converted into light energy, this process is also called electroluminescence. The cross-sectional view of a commercial LED is shown in figure (b). It consists of a p-layer, n-layer and a substrate. A transparent window is used to allow light to travel in the desired direction. An external resistance in series with the biasing source is required to limit the forward current through the LED. In addition, it has two leads; anode and cathode.

When the p-n junction is forward biased, the conduction band electrons on n-side and valence band holes on p-side diffuse across the junction. When they cross the junction, they become excess minority carriers (electrons in p-side and holes in n-side). These excess minority carriers recombine with oppositely charged majority carriers in the respective regions, i.e. the. electrons in the conduction band recombine with holes in the valence band as shown in the figure (c). During recombination process, energy is released in the form of light (radiative) or heat (non-radiative). For radiative recombination, a photon of energy hv is emitted. For non- radiative recombination, energy is liberated in the form of heat.

The colour of the light is determined by the energy band gap of the material. Therefore, LEDs are available in a wide range of colours such as blue (SiC), green (AlGaP) and red (GaAsP). Now a days, LED which emits white light (GalnN) is also available.

[OR]

(b) Give the applications of ICT in mining and agriculture sectors.
Answer:
(i) Agriculture
The implementation of information and communication technology (ICT) in agriculture sector enhances the productivity, improves the living standards of farmers and overcomes the Challenges and risk factors.

• ICT is widely used in increasing food productivity and farm management.
• It helps to optimize the use of water, seeds and fertilizers etc.
• Sophisticated technologies that include robots, temperature and moisture sensors, aerial images, and GPS technology can be used.
• Geographic information systems are extensively used in farming to decide the suitable place for the species to be planted.

(ii) Mining

• ICT in mining improves operational efficiency, remote monitoring and disaster locating system.
• Information and communication technology provides audio-visual warning to the trapped underground miners.
• It helps to connect remote sites.