Our team of subject expert teachers has prepared and reviewed the NCERT Solutions for Class 8 Science Chapter 7 Conservation of Plants and Animals are given here will help you to prepare well and score good numbers in exams.
Conservation of Plants and Animals NCERT Solutions for Class 8 Science Chapter 7
Class 8 Science Chapter 7 Conservation of Plants and Animals Exercise Questions and Answers
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 is known as ________.
(c) Migratory birds fly to faraway places because of ________ changes.
Differentiate between the following :
(a) Wildlife sanctuary and biosphere reserve.
|Wildlife Sanctuary||Biosphere Reserve|
|This is an area where wild animals are protected and preserved.||A biosphere reserve is a large area of protected land for conservation of wildlife, plant and animal resources, and traditional life of the tribals living in the area|
|The Wildlife sanctuary is a place found in isolation or in biosphere reserves||A biosphere reserve may also contain other protected areas like wildlife sanctuary.|
|Bori and Panch- machi are two wildlife sanctuaries in the Panels machi biosphere.||Panchmarhi, for example, is a biosphere reserve.|
(b) Zoo and wildlife sanctuary.
|It is a place where we protect animals.||Here, too, wild animals are protected and conserved.|
|Here artificial surroundings are made for animals in place of natural habitats.||They live in their natural habitats.|
|Here animals are supplied prepared food.||They get their food from forests (sanctuaries) themselves.|
(c) Endangered and extinct species.
|Endangered Species||Extinct Species|
|These are those species that are facing the danger of extinction.||They are the species that have already been banished from the earth.|
|Tiger is an example of an endangered species.||Dinosaur is an example of extinct species.|
(d) Flora and fauna.
|Flora is the plants found in a particular region||Fauna is the animals found in a particular region.|
|Sal, teak, mango, Jamun, silver ferns, Arjun, etc. are examples, of flora.||Chinkara, blue bull, barking deer, cheetah, leopard, wild dog, and wolf are examples of fauna.|
Discuss the effects of deforestation on the following :
(a) Wild animals
Wild animals: Deforestation leads to the change in the natural climate or habitat for the wild animals. Those animals, who have the forest as their habitat are called wild animals.
Environment: Deforestation increases the temperature and pollution level on the earth. It decreases the level of oxygen in the atmosphere with the increase of carbon dioxide (CO2) level and groundwater level is also lowered. The fertility of the soil will decrease and so the chances of natural calamities increase.
(c) Villages (rural area)
Villages (Rural areas): The decline in the rainfall, the decrease in soil fertility and the natural calamities like flood are the effects of deforestation, that adversely affects the villages.
(d) Cities (urban area)
Cities (Urban areas): Deforestation leads to an increase in carbon dioxide (CO2) concentration in the atmosphere, because of the least plantation. This also leads to global warming as an increase in the concentration of carbon dioxide traps the heat of sun rays. All these effects increase the pollution grade in the cities because of automobiles too.
Earth: Deforestation leads to soil erosion, change in the physical properties of the soil, removal of humus layer by which the hard and rocky layer exposes. All these ultimately convert the fertile land into desert, i.e., desertification.
(f) The next generation
The Next Generation: Deforestation shows the ugliest face to the survival of next-generation with problems at every step in their survival. Climatic conditions will be adversely affected. The environment will not be clean and healthy. There will be no food to eat and the next generation will face drought and floods.
What will happen, if:
(a) we go on cutting trees.
If we go on cutting trees, then the following situation will arrive :
- The climatic change will affect the environment due to global warming.
- The soil will become infertile due to regular flooding of topsoil. Consequently, the land will become a desert.
(b) the habitat of an animal is disturbed.
If the habitat of an animal is disturbed, the animal may not be in a position of getting its natural habitat as well as food. So, in the t long run, the animal will face extinction.
(c) the top layer of soil is exposed.
Removal of the top layer of soil by floods and heavy winds will expose the lower hard and rocky layers. This soil has less humus and less fertility. So, gradually the fertile land will be converted into a desert.
Answer in brief :
(a) Why should we conserve biodiversity?
We should conserve biodiversity so that the life existing on earth, their interrelationships, and their relationships with the environment would not get disturbed.
(b) Protected forests are also not completely safe for wild animals. Why?
It is because, despite all efforts, poachers keep killing or capturing the animals in these forests. That is why protected forests are also not completely safe for wild animals.
(c) Some tribals depend on the jungle. How?
Some tribals live in the jungle. Thre Jungle provides them food, the raw material for constructing their shelters, and raw materials to make things to earn their livelihood. That is why they are fully dependent on the forest.
(d) What are the causes and consequences of deforestation?
Causes of deforestation :
- Procuring land for cultivation.
- Building houses and factories.
- Making furniture or using wood as fuel.
- Some natural causes like forest fires and severe droughts.
The followings are the consequences of deforestation :
- Global warming disturbs the water cycle and reduces rainfall. Ultimately, drought is caused.
- Soil erosion and desertification of land.
- Melting of snow on the poles, which causes flooding of seas and oceans causing submerging of land by the sides of seas and oceans.
(e) What is Red Data Book?
Red Data Book is the sourcebook that keeps a record of all endangered animals and plants.
(f) What do you understand by the term migration?
Migration is the phenomenon of the movement of a species from its own habitat to some other habitat for a particular time period every year because of changing a climate or for the purpose of breeding.
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.
It is not at all justified to cut trees just to fulfill our demand. Trees are the habitat of many organisms including animals. They provide us with healthy oxygen and absorb harmful carbon dioxide. Trees also prevent soil erosion and natural calamities such as floods and droughts. They increase the fertility of the soil and help to conserve biodiversity.
The cutting of trees meets the demands of the growing human population, which leads to global warming, soil erosion, floods, droughts, and the greenhouse effect. So the destruction of trees will disturb the balance of nature. Hence, the forest must be conserved.
How can you contribute to the maintenance of the green wealth of your locality? Make a list of actions to be taken by you.
For the maintenance of the green wealth of my locality, I will prefer reforestation in the locality. I shall start a campaign, along with my friends, to make the people of the locality aware of the importance of trees/plants. Once people become conscious of the importance of plants, they will be requested to do the following:
- Every member of each family should plant at least one tree in the monsoon month and take care of them.
- During summer, they should assure the watering of the plants every day.
- On the occasion of birthdays, marriage ceremonies, and other happy occasions, they should gift their friends and relatives a plant in place of costly gifts.
- On national holidays, a seminar should be arranged to discuss subjects like the importance of plants, environment restoration, biodiversity, etc.
Explain how deforestation leads to reduced rainfall?
Deforestation leads to reduced rainfall, because the plants/trees that undergo transpiration, convert the groundwater into water vapour which moves upward and makes the clouds, which is the basic reason for rainfall.
Find out about the national parks in your state. Identify and show their location on the outline map of India.
I am a resident of Delhi. There is no national park in this state. However, three national parks Ranthambhor, Bharatpur, and Sariska are located in Rajasthan, which is close to Delhi. These are shown in the map given below.
Why should the paper be saved Prepare a list of the ways by which you can save paper?
The paper should be saved for the following reasons:
- A large number of trees can be saved by saving paper. This application can check deforestation.
- The saving paper also saves the energy and water that is needed for manufacturing paper.
- The number of harmful chemicals used in papermaking will show its least effect on living things by saving paper.
The ways to save paper are:
- Economical use of paper.
- Recycling of paper should be done.
- The paper should not be burnt.
Complete the word puzzle.
1. Species on the verge of extinction.
2. A book carrying information about endangered species.
5. Consequence of deforestation.
1. Species that have vanished.
3. Species found only in a particular habitat.
4. Variety of plants, animals, and microorganisms found in an area.
Class 8 Science Chapter 7 Conservation of Plants and Animals InText Questions and Answers
What is the purpose of making national parks, wildlife sanctuaries, and biosphere reserves?
The purpose of making national parks, wildlife sanctuaries, and biosphere reserves is to conserve and preserve forests and wild animals.
7.1 Deforestation and its Causes
Add more causes of deforestation to you. list and classify them into natural and man-made.
Apart from the causes given in the book of deforestation, other causes are as follows :
- Cutting plants and trees for different purposes – Man-made cause.
- Setting fires in the forest to clear the area – Man-made cause
- Flood – Natural cause
7.2 Consequences of Deforestation
How does deforestation reduce rainfall on the one hand and lead to floods on the other?
Deforestation reduces rainfall, as :
- It leads to global warming, which disturbs the water cycle.
- Cooling of the environment by transpiration is lacked due to deforestation.
Deforestation leads to flood, as :
- Trees help in lapping down water to recharge groundwater.
- Roots of trees hold soil and do not allow erosion.
We have studied in class VII that we get many products from the forests. List these products. Will we face a shortage of these products if we continue cutting trees?
The products we get from the forest are:
- Different kinds of fruits.
- Various types of medicinal and herbal plants and trees.
- Wood for making furniture.
- Wood for constructing houses.
- Grasses to construct thatched houses.
If we go on Cutting the trees of those forests, it will lead to their destruction and we will not only face the shortage of these products but the natural calamities also arise due to deforestation.
Animal life is also affected by deforestation. How? List the points and discuss them in your class.
The trees and grasses are the shelters of animals and birds. If deforestation continues, wildlife will be affected adversely. Wild animals may die because they won’t get their food and shelter in that situation.
7.3 Conservation of Forest and Wildlife
Having become aware of the effects of deforestation, Paheli, and Boojho are worried. They go to Prof. Ahmad and ask him how forests and wildlife can be saved.
The forests and wildlife can be saved by reforestation and to conserve wildlife in their natural habitat having many national parks, wildlife sanctuaries, and biosphere reserves.
Find out the number of national parks, wildlife sanctuaries, and biosphere reserves in your district, state, and country. Record in Table 7.1 (Textbook, P. 79). Show these areas in an outline map of your state and India.
I am a resident of Delhi. In Delhi, though there is a zoo there is no national park, wildlife sanctuary, or biosphere reserve.
|Protected area||National park||Wildlife sanctuary||Biosphere reserve|
|In my district||0||0||0|
|In my state||0||0||0|
|In my country||75||428||14|
7.4 Biosphere Reserve Activity 7.4
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?
Biodiversity refers to the variety of living organisms existing on the earth. The biodiversity of an area can be disturbed by the following activities :
- Killing or hunting animals for different purposes.
- Cutting trees and grasses which have medicinal importance.
- Setting fire in the forest for making, areas for agricultural purposes.
- Burning forests for human habitations.
- Making roads to pass to another side through a forest.
- These are some of the human activities because of which biodiversity gets disturbed.
These steps should be followed so that biodiversity may not get disturbed :
- Killing or hunting animals should be banned completely.
- Fires should not be set on in forests.
- Forests should not be cleared.
- More and more forests should be converted into Wildlife Sanctuaries, National Parks, or Biosphere Reserves.
7.5 Flora and Fauna
Try to identify the flora and fauna of your area and list them.
- Flora (trees and plants): Ferns, Jamun, mango, sal, teak, Arjun, pipal, Kadam, Kelkar, babool, etc., are some of the flora present in bur locality.
- Fauna: Wild dog, leopard, wolf, deer, chital, chinkara, blue bull, barking deer, etc., are some of the fauna present in our Ideality.
7.6 Endemic Species
I have heard that some of the endemic species may vanish. Is it true?
Yes, some of the endemic species may vanish, if their poaching is not stopped, or they are not looked after well or their original area is changed.
Find out the endemic plants and animals of the regions where you live.
- Endemic plants: Sal, wild mango, Jamun, and mahua.
- Endemic animals: Indian giant squirrel and bison.
7.7 Wildlife Sanctuary
What is the difference between a zoo and a wildlife sanctuary?
In both zoo and wildlife sanctuary, wild animals are conserved. In wildlife sanctuary, the animals get their natural habitat and naturally available food. On the other hand, in a zoo, these animals are provided artificial habitat. The food is also provided artificially.
The animals living in the zoo are looked after by animal-doctors, in case they fall sick, which is not possible in the forest. In spite of being given a lot of artificial facilities, the animals do not remain hale and hearty, whereas in their natural habitat they are free, hale, and hearty.
Visit a nearby zoo. Observe the conditions provided to the animals. Were they suitable for animals? Can animals live in an artificial setting instead of their natural habitat? In your opinion will the animals be comfortable in a zoo or in their natural habitat?
In the zoo, the tall trees and bushes are grown abundantly. There are a lot of ponds, water reserves, and artificial lakes made here and there. Fruit trees are also grown in plenty. To some extent, these facilities are suitable but not sufficient.
During winter, animals are provided with heaters to provide the heat. And during summer, an arrangement of coolers is made to make wild animal’s life comfortable.
But, I believe, these are not appropriate, because wild animals would like to live in the forest happily and not in these artificial settings. Wild animals will be far more comfortable in their natural habitat than in a zoo.
7.8 National Park
Are tigers still found in the forest?
Yes, tigers are still found in the forest, but their numbers are declining day by day due to poaching for their skin and teeth. Tiger is now declared as an endangered species.
What would happen if we had no wood? Is there any alternative available to wood?
If there were no wood, we would not have got any paper, fruits, or herbal medicines at all. But, there is an alternative for saving wood and have paper as well. The used paper could be recycled 5-7 times and can be used. If a student saves at least one sheet of paper in a day, he/she can thus save many trees in a year.
7.11 Recycling of Paper
Is there any permanent solution to the problem of deforestation?
Yes, there is a permanent solution for the problem of deforestation which is reforestation, i.e., restocking of the destroyed forests by planting new trees.