NCERT Solutions for Class 8 Science Chapter 7 – Conservation of Plants and Animals are available for PDF download. Our subject experts have tried to provide you with the precise and simplest answers that are best to clear the concepts and prepare well for the exams. The NCERT Solutions provided by Jagran Josh includes answers to the exercise questions given in chapter 7 of the latest NCERT Class 8 Science Book.
NCERT Solutions for Class 8 Science Chapter 7 – Conservation of Plants and Animals
1. Fill in the blanks:
(a) A place where animals are protected in their natural habitat is called a ______.
(b) Species found only in a particular area are known as ______.
(c) Migratory birds fly to far away places because of ______ changes.
(a) A place where animals are protected in their natural habitat is called a sanctuary.
(b) Species found only in a particular area are known as endemic.
(c) Migratory birds fly to far away 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
(a) Differences between wildlife sanctuary and biosphere reserve:
It is the area where animals are protected from any disturbance to them and their natural habitat.
It is the large area of protected land for the conservation of biodiversity.
It only provides protection and suitable living conditions to wild animals.
It helps in the conservation of various life forms such as wildlife, plant and animal resources and traditional life of the tribals living in the area.
(b) Difference between zoo and wildlife sanctuary
It is a place where animals are protected in an artificial habitat, for an exhibition.
It is a place where animals are protected from any disturbance to them and their natural habitat.
It is smaller in size.
It is very large in size.
(c) Difference between endangered and extinct species
These are the species which are on the verge of extinction.
These are the species that no longer exist on the earth.
Examples are blue whale, tiger, etc.
Examples are dodo, dinosaurs, etc.
(d) Flora and fauna
Plants of a particular area are known as flora.
Animals living in a particular area are known as fauna.
For example, sal, mango, jamun, etc., are the flora of Pachmarhi Biosphere Reserve.
For example, chinkara, barking deer, leopard, etc., are the fauna of Pachmarhi Biosphere Reserve.
3. Discuss the effects of deforestation on the following.
(a) Wild animals
(c) Villages (Rural areas)
(d) Cities (Urban areas)
(f) The next generation
(a) Wild animals: Forests provide food to wild animals and form their habitat. So, cutting down the forests in an area is not only destroying the natural habitat of animals but also depriving them of adequate food. This ultimately leads to the extinction of the animals of that particular ecosystem.
(b) Environment: Plants help to maintain the oxygen and carbon dioxide cycle in nature. Deforestation causes an increase in the carbon dioxide level and a decrease in the oxygen level. Accumulation of carbon dioxide in the environment causes global warming and disturbs the water cycle. Hence, rainfall pattern changes leading to natural calamities like droughts and floods.
(c) Villages (Ruaral Areas): Deforestation causes soil erosion and also results in floods. It also reduces rainfall. All these factors affect the agricultural activities in villages that in turn affects the life of people living in rural areas.
(d) Cities (Urban Areas): Deforestation in cities increases the risk of natural calamities like floods and drought can increase the risk of many natural calamities such as floods and droughts in that area.
(e) Earth: Deforestation increases the chances of occurrence of desertification, droughts and floods. It increases the level of carbon dioxide in the earth’s atmosphere that leads to global warming. This ultimately disturbs the climatic patterns occurring on the earth.
(f) The next generation: The next generation will face the adverse effects of deforestation. They will have to breathe in poisonous gases. Global warming, soil erosion, desertification, drought, floods and many other consequences of deforestation will make survival difficult for them.
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.
(a) If we go on cutting trees then:
→ Many animals will lose their natural habitat.
→ Top fertile layer of the soil will be removed due to soil erosion.
→ The increased level of carbon dioxide gas and decreased level of oxygen will lead to global warming.
→ Rainfall pattern will be disturbed that will lead to droughts and floods.
(b) If the habitat of an animal is disturbed then
→ It will not get the basic necessities like food, water, shelter and protection for its survival.
→ It will be forced to go to the nearby towns and villages in search of food and shelter where it could be killed or hunted by human beings.
→ It reach the level of extinction.
(c) If the top layer of soil is exposed then
→ It will be removed or washed away by winds and waters leaving behind the hard and infertile layer of the soil.
→ The water holding capacity of the soil will be decreased.
→ The continued soil erosion will lead to 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?
(a) In biodiversity, all the life forms are interrelated or mutually dependent for their survival. Thus, destruction of any one part of this chain will automatically destroy the other. Therefore, we should conserve biodiversity to maintain balance in nature.
(b) Protected forests are also not completely safe for wild animals because the capturing and killing of animals by poachers and the tribal people is still rampant in these areas.
(c) Some tribals depend on the jungle to meet their basic needs like food, shelter, clothing, etc. Forests are the only resources for the fulfillment of their day to day needs.
(d) Causes of deforestation are:
→ Increased use of land for urbanization and industrialization.
→ Increased use of land for cultivation to meet the food requirements of the everlasting population.
→ Natural reasons like forest fires and droughts.
Consequences of deforestation are:
→ Depletion of top fertile layer of soil due to soil erosion.
→ Decrease in groundwater level.
→ Increase in temperature of the earth causing global warming.
→ Increase in flash floods.
→ Extinction of many flora and fauna.
(e) Red Data Book is the source book which keeps a record of all the endangered animals and plants.
(f) Migration refers to the movement of an organism or a group of organisms from its natural habitat to another place at a particular time every year to avoid unfavourable climatic conditions or for the purpose of breeding.
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.
No, it is not justified to cut trees to meet the ever increasing demands of human population. Forests serve as the habitat of several species of birds and animals. In addition to this, they act as air purifiers by taking in the harmful carbon dioxide gas and releasing out the life giving oxygen gas. This way they are helping in reducing the temperature of the earth because excessive carbon dioxide in the atmosphere causes global warming. Forests also help in increasing rainfall due to the process of water evaporation from the leaves of plants and trees. They prevent soil erosion and natural calamities like floods and droughts. They help to preserve the fertility of the soil.
On the other hand, uncontrolled cutting of forests will lead to the following drastic consequences:
→ global warming
→ soil erosion
→ greenhouse effect
→ flash floods
→ extinction of several valuable species of wild animals.
In this way, destruction of forests will disturb the nature’s balance that is not good for the human population as well. Hence, we must do efforts to preserve our forests.
7.How can you contribute to the maintenance of green wealth of your locality? Make a list of actions to be taken by you.
We can contribute to the maintenance of green wealth of our locality by:
→ growing new plants.
→ watering the plants regularly.
→ not destroying the already existing green plants and trees in our locality.
→ Encouraging awareness among the people about the importance of green wealth.
→ preventing people from cutting down the trees.
8.Explain how deforestation leads to reduced rainfall.
Plants absorb water from the soil and evaporates it through their leaves. These water vapours then form clouds and bring rains on the earth. Deforestation causes a decrease in the water absorption from the soil which means less water evaporates to form clouds. This ultimately leads to a reduced rainfall.
10.Why should paper be saved? Prepare a list of ways by which you can save paper.
Paper should be saved because it is made from the trees. It takes around seventeen full grown trees to make one tonne of paper. Thus, by saving paper we are actually saving trees that are very important to maintain a balance of nature.
Various ways by which we can save paper are:
→ Recycling of used papers.
→ Avoiding the wastage of paper.
→ Spreading awareness about the importance of paper.
11. Complete the world puzzle.
1. Species on the verge of extinction.
2. A book carrying information about endangered species.
5. Consequence of deforestation.
1. Species which have vanished.
3. Species found only in a particular habitat.
4. Variety of plants, animals and microorganisms found in an area.
2. RED DATA BOOK
All these solutions can also be saved in PDF from the following link:
Download NCERT Solutions for Class 8 Science Chapter 7 in PDF
Also, check the NCERT Books and NCERT Solutions for all major subjects of Class 8: