DAV Class 8 Science Chapter 8 Question Answer
DAV Class 8 Science Chapter 8 Solutions: DAV Solutions for Class 8 Science Chapter 8 Conservation of Plants and Animals Question Answer is given below. Here DAV Class 8 Science Chapter 8 Question Answer is provided with great explanation.
A. Fill in the blanks.
1. International Day for biological diversity is observed on ___________.
2. A group of organisms, capable of interbreeding under natural conditions, is known as a ___________.
3. ___________ species are the species that are found only in a particular area.
4. ___________ is an important reserve for Project Tiger.
5. ___________ sanctuary in Odisha is the breeding ground for the ‘giant olive ridley turtle’ which migrate here from the Pacific Ocean.
Answer: (1) May 22 (2) species (3) endemic (4) Bandipur National Park (5) Gahirmatha Turtle
B. Match the following.
Answer: (1) b (2) d (3) e (4) a (5) c
C. Tick the correct option.
1. Protection, and preservation of wildlife and natural resources, is known as-
Answer: conservation
2. The cheetah is a vulnerable species because-
Answer: it will be ‘extinct soon.
3. Plants, found in a particular area, are referred to as-
Answer: flora
4. Which one of the following is not an outcome of deforestation in an area?
Answer: increased rainfall.
5. A region, in which ‘conservation of biodiversity’ in its natural habitat is practised, is known as a-
Answer: national park
D. Answer the following questions in brief.
1. How have ‘urbanisation and industrialisation’ led to a large scale deforestation’?
Answer: Forest land is being sacrifices for massive development projects that have become a necessary part of urbanization and industrialization. Forests are being used as a source of raw material for paper, medicines, pulp, and furniture etc. All these factors have led to the indiscriminate cutting down of trees in the forests.
2. A new species X is introduced in a forest. How is it likely to affect the local species of the area?
Answer: If a new species is introduced in the particular area, the local species will be affected in the following ways:
- The local species may not get proper shelter, water and food for their survival.
- They may prey on the local species.
- It may change food chain or food web.
- Some the species may extinct.
3. What is a Biosphere Reserve? Name two biosphere reserves in India.
Answer: It is an international protected area (designated by UNSECO); meant to have a balanced relationship between man and nature, along with promoting sustainable development.
Two examples of biosphere reserves in India are: Nilgiri Biosphere Reserve and Nanda Devi Biosphere Reserve.
4. How does the ‘Red data book’ help in protecting biodiversity?
Answer: Red Data Book is a document that keeps a record of all the endangered species of animals, plants, and fungi in a country or a state. With the help of this book, we can estimate the risk and provides a framework or guidelines for implementing protective measures for endangered species.
5. Why do some birds and animals migrate?
Answer: Some birds and animals need to migrate to find abundant food and a favourable place to breed.
6. How do birds ‘get helped’ in navigation while undertaking long distance flights?
Answer: Birds have much sharper eyesight and better virtual memory of ground clues than humans. However, in long-distance flights, birds appear to navigate with the help of the Sun and stars, possibly in combination with a ‘reading’ of the Earth’s magnetic field. This is achieved through an inbuilt ‘magnetic compass, which is a tiny mass of tissue, between the eye and the brain, in birds.
7. Distinguish between a National Park and a Wildlife Sanctuary.
Answer: Distinguish between a National Park and a Wildlife Sanctuary are:
| National Park | Wildlife Sanctuary |
| No human activities are allowed. | Human activities are allowed. |
| Boundaries are fixed and defined. | There are no fixed boundaries. |
| Not usually open to the public. | It is open to the general public. |
E. Answer the following questions.
1. Explain how deforestation can result in droughts and floods.
Answer: The roots of the trees help the soil to bind up properly. Deforestation of trees led to the frequent floods and drought, because the soil loosens up the binding due to cutting of trees. Thus, when there is rain, soil erosion and flood take place.
As for drought, deforestation leads to global warming and reduces the water cycle of that place resulting to less rain fall.
2. ‘Extinction of tiger can destabilise the entire forest ecosystem and result in a large-scale loss of biodiversity.” Justify this statement.
Answer: If the tigers get extinct, then the food chain will get disturbed and the number of herbivorous animals will increase. This will result in excess of grazing of plants. Plants are the ultimate source of food, therefore, there will be shortage of food for everyone and many species will face extinction.
3. Why are endemic species at a greater risk of becoming extinct? List the human action related causes’ that are responsible for their extinction.
Answer: Endemic species are found only in a particular area; hence, it is all the more important to conserve them. Habitat loss, overexploitation, introduction of new species and disruption of ecosystems, are the main reasons for the extinction of endemic species.
4. “The growing human population poses a grave threat to biodiversity”. Justify this statement.
Answer: An increase in human population is affecting biodiversity by taking up more forest land which treats the lives of various plants and animals. Forests are also being used as a source of raw material for various industries. Deforestation has led to both domestic and global consequences.
5. Explain the difference between extinct, endangered and vulnerable species.
Answer: Difference between extinct, endangered and vulnerable species are:
Extinct: A plant, or an animal, which is now not found anywhere on the earth are extinct species.
Endangered: A Species of plant, or an animal, which is at a high risk of extinction in the near future.
Vulnerable: The plants and animals that are found only in one particular geographical area, and nowhere else are vulnerable species.
6. List five ways in which you, as an individual, can contribute to conserving forests and wildlife.
Answer: Five ways in which we, as an individual, can contribute to conserving forests and wildlife are:
1. By planting more and more trees.
2. By reducing wastage of paper
3. By creating awareness among the people to conserve forest and wildlife.
4. By optimum utilization of forest products.
5. By adopting the policy of three Rs-Reduce, Reuse, Recycle.
