Solutions to NCERT Class 8 Science Chapter 5 Conservation of Plants and Animals

Hello students! We have prepared excellent Chapter 5 solutions to help you prepare. All the exercise questions, extended learning activities, in-text questions and activities for this chapter have been answered in this material. We have taken care to answer all questions you might have on this chapter. Study the material in detail and you will be prepared for your exams.

Solutions to Exercises (Page No 62) of NCERT Class 8 Science Chapter 5 Conservation of Plants and Animals

1. Fill in the blanks.

(a) A place where animals are protected in their natural habitat is called _________.

(b) Species found only in a particular area are known as _________.

(c) Migratory birds fly to faraway places because of __________ changes.

Answers:

(a) A place where animals are protected in their natural habitat is called sanctuary.

(b) Species found only in a particular area are known as endemic.

(c) Migratory birds fly to faraway places because of climatic changes.

2. Differentiate between the following.

(a) Wildlife sanctuary and biosphere reserve

(b) Zoo and wildlife sanctuary

(c) Endangered and extinct species

(d) Flora and fauna

Answers:

(a) Wildlife sanctuary and biosphere reserve

Wildlife sanctuaries are meant to protect animal life from danger such as poaching, whereas biosphere reserve is meant for the conservation of biodiversity. Biosphere reserves may contain wildlife sanctuaries within them. For example, Pachmarhi Biosphere Reserve contains two wildlife sanctuaries named Bori and Pachmarhi.

(b) Zoo and wildlife sanctuary

Zoo is where animals captured from the forest are kept in enclosures for public exhibition. Wildlife sanctuary is where wild animals are protected in their natural habitats. Animals struggle to adapt in their confined cages in a zoo, whereas in a wildlife sanctuary they are at home in their natural habitat.

(c) Endangered and extinct species

Endangered species are species which are in huge danger of extinction, whereas extinct species are those that no longer exist. We can save an endangered species from extinction, whereas extinct species cannot be saved.

(d) Flora and fauna

Plant species from a particular area are called flora, whereas animal species from a particular area are called fauna.

3. Discuss the effects of deforestation on the following.

(a) Wild animals

(b) Environment

(c) Villages (Rural areas)

(d) Cities (Urban areas)

(e) Earth

(f) The next generation

Answers:

(a) Wild animals

The effect of deforestation on wild animals is loss of habitat. As more forests are cut down, animals lose food and shelter and their population gradually decreases. Certain animal species might even become extinct. Due to loss of habitat animals move to other habitats, thereby disturbing the ecosystem.

(b) Environment

The effect of deforestation on the environment is the disturbance of ecological balance. It increases the temperature and pollution level. The level of carbon dioxide in the atmosphere increases and groundwater level gets lowered. It also leads to soil erosion and hence floods. Droughts occur due to global warming.

(c) Villages (Rural areas)

The effect of deforestation on villages (rural areas) is loss of soil fertility. Fewer trees result in more soil erosion and hence removal of the fertile top layer humus. This exposes the lower, hard and rocky layers and gradually the fertile agricultural land gets converted into deserts. Also, deforestation results in wild animals straying into villages.

(d) Cities (Urban areas)

The effects of deforestation on cities (urban areas) are increase in pollution and carbon dioxide levels, which leads to increase in temperature. Natural disasters like floods and drought in cities are also brought about by deforestation. The groundwater reserves are also depleted. In general, the water cycle gets disturbed.

(e) Earth

The effects of deforestation on Earth are pollution and global warming, less soil fertility, soil erosion, floods, drought and decreased groundwater level. All these factors work together to destroy the ecological balance of the Earth.

(f) The next generation

The effects of deforestation on the next generation are destruction of the environment. Increased pollution, global warming, desertification, floods and drought would happen. Due to these the water cycle and food chain would get disrupted. There would be lack for food, water and clean air for the next generation.

4. What will happen if

(a) we go on cutting trees

(b) the habitat of an animal is disturbed

(c) the top layer of soil is exposed

Answers:

(a) we go on cutting trees

If we go on cutting trees the temperature, pollution level and carbon dioxide in the atmosphere will increase. This will lead to global warming. Groundwater will decrease and floods and droughts will occur frequently. Soil erosion will decrease soil fertility, which will lead to desertification. The ecological balance will be disturbed.

(b) the habitat of an animal is disturbed

If the habitat of an animal is disturbed it will move to other habitats in search of food and shelter. This would disturb the delicately balanced ecosystem of the habitat they move to. They might even stray into rural and urban areas populated by humans.

(c) the top layer of soil is exposed

If the top layer of soil is exposed, the lower, hard and rocky layers will be exposed. This soil has less humus and is less fertile. Due to continued erosion, it will gradually get converted into deserts. This is called desertification.

5. Answer in brief.

(a) Why should we conserve biodiversity?

(b) Protected forests are also not completely safe for wild animals. Why?

(c) Some tribals depend on the jungle. How?

(d) What are the causes and consequences of deforestation?

(e) What is Red Data Book?

(f) What do you understand by the term migration?

Answers:

(a) Why should we conserve biodiversity?

We should conserve biodiversity to maintain the delicate ecological balance. The variety of plants, animals and microorganisms which comprise biodiversity are all interdependent on each other for food and shelter. Extinction of one species could mean extinction of others. This would also affect humans.

(b) Protected forests are also not completely safe for wild animals. Why?

Protected forests are also not completely safe for wild animals because people living in the neighbourhood encroach on the forests and destroy them. Also, illegal hunting and poaching sometimes happens even in protected forests, which poses a danger to animals.

(c) Some tribals depend on the jungle. How?

Tribals heavily depend on the jungle for food, water, grazing by their livestock, medicinal plants, building materials, firewood etc.

(d) What are the causes and consequences of deforestation?

The causes of deforestation are:

• Urban development like building highways and houses.
• Industrial development like building of factories.
• Expansion of agricultural land.
• Making furniture or using wood as fuel.
• Natural causes such as forest fires and severe droughts.

The consequences of deforestation are:

• Increase in carbon dioxide in the atmosphere.
• Increase in temperature and pollution.
• Global warming.
• Decreased rainfall.
• Soil erosion and reduced soil fertility.
• Natural calamities such as floods and droughts.

 
(e) What is Red Data Book?

Red Data Book is the source book which keeps a record of all the endangered animals and plants. Red Data Book is maintained internationally by an organisation called International Union for Conservation of Nature (IUCN). India also maintains Red Data Book for plants and animals found in India.

(f) What do you understand by the term migration?

The term migration refers to birds and animals moving to far away areas every year during a particular time because of climatic changes. For example, birds fly to far away areas for laying eggs as the weather in their natural habitat becomes very cold and inhospitable.

6. In order to meet the ever-increasing demand in factories and for shelter, trees are being continually cut. Is it justified to cut trees for such projects? Discuss and prepare a brief report.
Answer:
I believe it is not justified to cut trees for industrial and residential development projects.

Deforestation disturbs the delicate ecological balance of nature:

Global Warming: Deforestation leads to increased carbon dioxide levels in the atmosphere because there are less trees to take in carbon dioxide. This would lead to increase in atmospheric temperature and global warming as carbon dioxide traps the heat rays reflected by the earth.

Droughts: The increase in temperature would reduce rainfall and cause droughts.

Soil Erosion: Fewer trees result in more soil erosion. This would result in the soil becoming less fertile and would lead to desertification.

Reduced Groundwater Levels and Floods: Deforestation also leads to a decrease in the water holding capacity of the soil. The movement of water from the soil surface into the ground (infiltration rate) is reduced. This reduces groundwater levels. Also, the water rushes over the soil surface and may cause flash floods.

Reduced Habitat for Plants and Animals: Plants and animals would lose their natural habitats. Animals would migrate elsewhere, which would disturb the ecological balance of the area. The food chain would be disrupted and it might even lead to extinction of certain species.

Some potential solutions to solve the problem could be selective logging and alternative construction materials to reduce the need for timber. This way the green abundance of our forests could be preserved for many generations to come.

7. How can you contribute to the maintenance of green wealth of your locality? Make a list of actions to be taken by you.
Answer:
To maintain the green locality of my locality, I pledge to

• Plant more trees in my immediate neighbourhood and my surrounding neighbourhoods.
• Maintain the trees by watering them regularly.
• Organize awareness events to educate people of the importance of trees and harmful effects of climate change.
• Encourage the local municipality to prohibit illegal cutting of trees.
• Recycle paper.

8. Explain how deforestation leads to reduced rainfall.
Answer:
Deforestation leads to reduced rainfall due to reduced transpiration. Trees give out a lot of water vapour from the leaves by process of transpiration. This water vapour forms clouds which brings about rainfall. Absence of trees would lead to reduced transpiration and hence reduced rainfall.

9. Find out about national parks in your state. Identify and show their location on the outline map of India.
Answer:
The national parks in the state of West Bengal are listed below:

(i) Singalila National Park

(ii) Neora Valley National Park

(iii) Gorumara National Park

(iv) Buxa Tiger Reserve

(v) Jaldapara National Parl

(vi) Raiganj National Park The above are located on the map of West Bengal below:

The same national parks located on the map of India are shown below:

10. Why should the paper be saved? Prepare a list of ways by which you can save paper.
Answer:
Paper should be saved because it takes a lot of trees to produce paper. For example, it takes 17 grown trees to make one tonne of paper. Cutting of trees for paper disturbs the ecological balance of the planet. If we save paper, we save not only trees but also energy and water for manufacturing paper.

A list of ways by which you can save paper include:

• Sending paper for recycling.
• Using paper judiciously and avoiding wastage.
• Use digital technology to take notes and keep records.
• Using reusable cloth bags instead of paper bags.

11. Complete the word puzzle.

Down

1. Species on the verge of extinction.

2. A book carrying information about endangered species.

5. Consequences of deforestation.

Across

1. Species which have vanished.

3. Species found only in a particular habitat.

4. Variety of plants, animals and microorganisms found in an area.

Answer:

Solutions to Extended Learning – Activities and Projects (Page No 64) of NCERT Class 8 Science Chapter 5 Conservation of Plants and Animals

1. Plant at least five different plants in your locality during this academic year and ensure their maintenance till they grow.

Answer:

Solution to Extended Learning Problem 1

2. Promise yourself that this year you will gift at least 5 plants to your friends and relatives on their achievements, or on occasions like birthdays. Ask your friends to take proper care of these plants and encourage them to gift plants to their friends on such occasions. At the end of the year count the plants that have been gifted through this chain.

Answer:

Solution to Extended Learning Problem 2

3. Is it justified to prevent tribals from staying in the core area of the forest? Discuss the matter in your class and note down the points for and against the motion in your notebook.

Answer:

Solution to Extended Learning Problem 3

4. Study the biodiversity of a park nearby. Prepare a detailed report with photographs and sketches of the flora and fauna.

Answer:

Solution to Extended Learning Problem 4

5. Make a list of the new information you have gathered from this chapter. Which information did you find the most interesting and why?

Answer:

Solution to Extended Learning Problem 5

6. Make a list of various uses of papers. Observe currency notes carefully. Do you find any difference between a currency paper and paper of your notebook? Find out where currency paper is made.

Answer:

Solution to Extended Learning Problem 6

7. Karnataka Government had launched ‘Project Elephant’ to save Asian elephants in the state. Find out about this and other such campaigns launched to protect threatened species.

Answer:

Solution to Extended Learning Problem 7

Solutions to In Text Questions of NCERT Class 8 Science Chapter 5 Conservation of Plants and Animals

1. (Page 53) What is the purpose of making national parks, wildlife sanctuaries and biosphere reserves?
Answer:
The purpose of making national parks, wildlife sanctuaries and biosphere reserves is to conserve and protect the plants, wildlife and traditional life of tribals living in that area.

2. (Page 53) How does deforestation reduce rainfall on the one hand and lead to floods on the other?
Answer:
Deforestation reduces rainfall because of loss of trees and hence less transpiration from trees. On the other hand, it leads to floods. Trees slow down rainfall and prevent it from hitting the ground directly. The root system also facilitates water infiltration in the soil. Hence, the absence of trees leads to floods.

3. (Page 54) We have studied in Class VII that we get many products from forests. List these products. Will we face shortage of these products if we continue cutting trees?
Answer:
The products we get from forests are timber and wood, fruits, seeds, medicines, rubber, honey, bamboo, pulp and paper etc. Yes, we will face shortage of these products if we continue cutting trees.

4. (Page 58) What is the difference between a zoo and a wildlife sanctuary?
Answer:
Zoo is a place where animals are kept in man-made enclosures for public exhibition, whereas a wildlife sanctuary is where animals live protected in their natural habitats.

5. (Page 60) What would happen if we had no wood? Is there any alternative available to wood? I know that paper is one of the important products we get from forests. I wonder whether there are any alternatives available for paper!
Answer:
If we had no wood, we would lack essential products like furniture, paper etc. For certain applications bamboo, plastic and agricultural residues can be used in place of wood. Yes, there are alternatives available for paper such as digital platforms and electronic documents, paper made from cotton etc.

6. (Page 60) Is there any permanent solution to the problem of deforestation?
Answer:
Yes, the permanent solution to the problem of deforestation is reforestation, which is restocking of the destroyed forests by planting new trees. Reforestation can be done naturally too. If the deforested area is left undisturbed, it re-establishes itself.

Solutions to All Activities of NCERT Class 8 Science Chapter 5 Conservation of Plants and Animals

1. Complete Activity 5.1 (Page 53). Add more causes of deforestation to your list and classify them into natural and man-made.

Answer:

Solution to Activity 5.1

2. Complete Activity 5.2 (Page 54). Animal life is also affected by deforestation. How? List the points and discuss them in your class.

Answer:

Solution to Activity 5.2

3. Complete Activity 5.3 (Page 55). Find out the number of national parks, wildlife sanctuaries and biosphere reserves in your district, state and country. Record in Table 5.1. Show these areas in an outline map of your state and India.

Answer:

Solution to Activity 5.3

4. Complete Activity 5.4 (Page 56). List the factors disturbing the biodiversity of your area. Some of these factors and human activities may disturb the biodiversity unknowingly. List these human activities. How can these be checked? Discuss in your class and write a brief report in your notebook.

Answer:

Solution to Activity 5.4

5. Complete Activity 5.5 (Page 57). Try to identify the flora and fauna of your area and list them.

Answer:

Solution to Activity 5.5

6. Complete Activity 5.6 (Page 57). Find out the endemic plants and animals of the region where you live.

Answer:

Solution to Activity 5.6

7. Complete Activity 5.7 (Page 58). Visit a nearby zoo. Observe the conditions provided to the animals. Were they suitable for the animals? Can animals live in artificial setting instead of their natural habitat? In your opinion, will the animals be comfortable in a zoo or in their natural habitat?

Answer:

Solution to Activity 5.7

Extra Questions to Complement Solutions to NCERT Class 8 Science Chapter 5 Conservation of Plants and Animals

Very Short Answer Type:

1. Give a natural cause of deforestation.
Answer:
Forest fires.

2. Why does deforestation increase the amount of carbon dioxide in the atmosphere?
Answer:
Because trees absorb carbon dioxide. Less number of trees would mean that less carbon dioxide is absorbed.

3. Which properties of the soil change due to deforestation?
Answer:
Nutrient content and texture.

4. Name a protected area for animals.
Answer:
Wildlife sanctuary.

5. Where is Pachmarhi Biosphere Reserve located?
Answer:
Satpura range in Madhya Pradesh.

6. What is illegal killing of animals called?
Answer:
Poaching.

7. Name a non-living component of the ecosystem.
Answer:
Climate.

8. How many trees does it take to make one tonne of paper.
Answer:
17.

9. Name the act in India which is aimed at preservation of our forests.
Answer:
Forest (Conservation) Act.

10. Apart from reforestation, how can we save forests?
Answer:
By reducing waste and recycling of paper.

Multiple Choice Questions (MCQ):

1. Which one of the following statements is true about a Biosphere Reserve? (NCERT Exemplar)

(a) It is a protected area where only endemic species live.
(b) It is meant only for the conservation of plants and animals.
(c) It is meant to conserve both, the biodiversity and the culture of that area.
(d) There are no other protected areas within its limits

Answer: (c) It is meant to conserve both, the biodiversity and the culture of that area.

2. The numbers of which animal in the Satpura Tiger Reserve has increased significantly?

(a) Lions
(b) Tigers
(c) Elephants
(d) Wild buffalo

Answer: (b) Tigers

3. Which is true about effects of deforestation on soil?

(a) Increase of soil erosion and decrease of soil fertility.
(b) Decrease of soil erosion and increase of soil fertility.
(c) Increase in water holding capacity of soil
(d) Decrease in water holding capacity of soil

Answer: (a) and (d)

4. Which statement is incorrect about endangered species? (NCERT Exemplar)

(a) Their number has decreased drastically.
(b) They might become extinct in the near future.
(c) They pose a danger to other animals.
(d) Their natural habitat needs to be protected.

Answer: (c) They pose a danger to other animals.

5. Which of the following activities are people living in wildlife sanctuaries not allowed to do?

(a) Graze their livestock
(b) Hunt small animals
(c) Collect medicinal plants
(d) Collect firewood

Answer: (b) Hunting small animals

Short Answer Type:

1. What is biosphere?
Answer:
Biosphere is that part of the earth in which living organisms exist or which supports life.

2. What is a biosphere reserve?
Answer:
Biosphere reserves are areas meant for conservation of biodiversity, which is the variety of plants, animals and microorganisms generally found in an area.

3. Name the smaller protected areas inside Pachmarhi Biosphere Reserve.
Answer:
The Pachmarhi Biosphere Reserve consists of one national park named Satpura and two wildlife sanctuaries names Bori and Pachmarhi.

4. Name two flora and two fauna which are endemic of Pachmarhi Biosphere Reserve.
Answer:
Two flora of Pachmarhi Biosphere Reserve are sal and wild mango. Two fauna of the reserve are bison, Indian giant squirrel.

5. A new species X is introduced in a forest. How is it likely to affect the local species of that area? (NCERT Exemplar)
Answer:
There would be increased competition for food, leading to starvation for certain species. The food chain would get disrupted. Also, certain local species of animals would get displaced to other habitats.

6. Name some activities which are not allowed in all national parks?
Answer:
Human activities such as grazing, poaching, hunting, capturing of animals, collection of firewood, medicinal plants etc are not allowed.

7. How is ecosystem different from biodiversity.
Answer:
Ecosystem is made up of all plants, animals and microorganisms in an area along with non-living components like climate, soil, rivers etc. Biodiversity only refers to all organisms existing on earth, it does not include non-living components.

8. Give two reasons why birds migrate.
Answer:
Two reasons why birds migrate are as follows:

(i) Cold and inhospitable weather in their natural habitat.

(ii) To find adequate nesting grounds to lay eggs.

9. How can natural reforestation take place?
Answer:
Natural reforestation takes place if the deforested area is left undisturbed by natural seed dispersal. Seeds carried by wind, water, rain etc gradually populate the deforested area. Seeds are also spread through animal waste.

10. How are droughts caused by deforestation?
Answer:
Deforestation leads to an increase in carbon dioxide in the atmosphere, which leads to an increase in atmospheric temperature. This increase in temperature disturbs the water cycle and may reduce rainfall. This leads to droughts.

Fill in the Blanks:

smaller, desertification, rock shelters, Project Tiger, bigger, dinosaurs

(a) _________ became extinct a long time ago.

(b) _________ found in Satpura National Park give evidences of prehistoric human life.

(c) _________ animals are in much more in danger of extinction than _________ animals.

(d) Large amount of soil erosion leads to _________.

(e) _________ was launched by the government to protect the tigers in our country.

Answers:

(a) Dinosaurs became extinct a long time ago.

(b) Rock shelters found in Satpura National Park give evidences of prehistoric human life.

(c) Smaller animals are in much more in danger of extinction than bigger animals.

(d) Large amount of soil erosion leads to desertification.

(e) Project Tiger was launched by the government to protect the tigers in our country.

Match and Pair:

Column A	Column B
(i) Black buck	(a) Cotton paper
(ii) Red Data Book	(b) Endemic to Pachmarhi
(iii) Currency notes	(c) Endangered species
(iv) Giant squirrel	(d) Pollution
(v) Deforestation	(e) Record of endangered plants and animals

Answer: The correct table is shown below:

Column A	Column B
(i) Black buck	(c) Endangered species
(ii) Red Data Book	(e) Record of endangered plants and animals
(iii) Currency notes	(a) Cotton paper
(iv) Giant squirrel	b) Endemic to Pachmarhi
(v) Deforestation	(d) Pollution

++++++++++++++

Frequently Asked Questions (FAQs) on NCERT Solutions to Class 8 Science Chapter 5 Conservation of Plants and Animals