Here are important questions from NCERT Class 8 Science Chapter 7 Conservation of Plants and Animals.

1. ………………………… is a major threat to the survival of all organisms.

Deforestation

2. What is deforestation?

Deforestation is the clearing of forests for using that land for other purposes.

3. Why does deforestation occur?

Trees in the forests are cut down to procure land for cultivation, to build houses and factories. Timber is used to make furniture and wood is used as fuel.

4. What are some natural causes of deforestation?

Some natural causes of deforestation are forest fires and severe droughts.

5. What are the consequences of deforestation?

Deforestation increases the temperature and pollution level on earth. When trees are cut down, the level of carbon dioxide in the atmosphere increases and ground water level falls. Thus, deforestation upsets the balance in nature.

6. How does deforestation accelerate the pace of global warming?

Trees need carbon dioxide for photosynthesis. When there are fewer trees, the amount of carbon dioxide absorbed by them will decrease. As a result, more carbon dioxide will stay in the atmosphere. This leads to global warming because carbon dioxide traps the heat rays reflected by earth. Hence, temperature of the earth and the atmosphere increases leading to a phenomenon called global warming.

7. How does deforestation affect the fertility of the soil?

The roots of trees play a huge role in preventing soil erosion. When there are fewer trees, it will lead to more soil erosion. The erosion of the top layer of the soil will expose lower, hard and rocky layers. Since these layers have less humus, they are not very fertile. Thus, deforestation affects the fertility of the soil.

8. What is desertification?

When fertile lands get converted into deserts, it is called desertification.

9. How does deforestation lead to floods?

Deforestation reduces the infiltration rate and the water holding capacity of the soil. Because the soil cannot absorb much water, the rainwater just flows away leading to floods.

10.What is biosphere?

Biosphere is that part of the earth in which living organisms exist.

11. What is biodiversity?

Biodiversity is the variety of organisms existing on the earth, their interrelationships and the relationship they have with the environment.

12. What are wildlife sanctuaries and biosphere reserves?

These are protected areas for conservation of plants and animals present in that area.

13. ………………………. are areas meant for the conservation of biodiversity.

Biosphere reserves

14. What are flora and fauna?

These are plants and animals typically found in an area.

15. What are endemic species?

These are species of plants and animals which are found exclusively in a particular area.

16. Name two trees endemic to the Pachmarhi Biosphere reserve.

Sal and wild mango

17. What are the factors endangering the existence of endemic species?

Destruction of their species, increasing population and introduction of new species may affect the natural habitat of endemic species and endanger their existence.

18. What is a species?

Species is a group of population which are capable of interbreeding.

19. What is the difference between a zoo and a wildlife sanctuary?

In wildlife sanctuaries, animals can live in their own natural habitat and receive protection from threats like poaching. Zoos also provide protection to animals, but in zoos animals are kept in enclosures or artificial settings far away from their natural habitats.

20. …………………………. is the first Reserve Forest of India.

Satpura National Park

21. Satpura National Park is part of ……………………………

Pachmarhi Biosphere Reserve

22. What is Project Tiger?

This is an initiative of the government of India to protect tigers in the country.

23. What are endangered animals?

These are animals whose numbers are falling to such a low level that they might face extinction.

24. What are the main differences between wildlife sanctuaries and national parks?

Both wildlife sanctuaries and national parks are meant for protecting animals from poaching and other threats. However, people living in wildlife sanctuaries are allowed to graze their animals and collect medicinal plants or firewood from the forests. In national parks, human activities such as grazing or collection of medicinal plants and firewood are not allowed.

25. What is an ecosystem?

The term ecosystem is used to refer to all the plants, animals and microorganisms in an area along with non-living components such as climate, soil, river deltas etc.

26. What is the Red Data Book?

This is a source book which contains a record of all the endangered animals and plants.

27. What are migratory birds?

These are birds which fly to far-away places every year during a particular time for a specific purpose. For example, birds living in cold climates fly south in winter to protect themselves from the cold. Birds may also migrate from colder areas for the purpose of breeding.

28. What is reforestation?

Reforestation is the restocking of destroyed forests by planting new trees.