Class 8 Science · 27 questions · 27 with answers
Wild buffalo is an endangered species because
(a) its population is diminishing
Which one of the following changes may occur due to desertification?
(d) Conversion of fertile land into a desert.
Which one of the following statements is true about a Biosphere Reserve?
(c) It is meant to conserve both, the biodiversity and the culture of that area.
The place meant for conservation of biodiversity in their natural habitat are (i) Zoological garden (iii) Wildlife sanctuary (ii) Botanical garden (iv) National park
(c) iii & iv;
Which one of the following statements is true about endemic species?
(a) They are found exclusively in a specific habitat.
Which of the following feature is correct for a wildlife sanctuary?
(a) It is an artificially created protected area for animals.
Which statement is incorrect about endangered species?
(c) They pose a danger to other animals.
What do black buck, elephant, python and golden cat together represent in a forest?
(a) fauna
The Red Data Book keeps a record of all the
(iii) endangered plants.
Migratory birds fly to far away areas during a particular time of a year. Which of the following conditions present in their habitat during that time are responsible for this behaviour? (i) Unavailability of food. (ii) Extreme weather conditions. (iii) Over crowding. (iv) Lack of nesting areas.
(b) i & ii;
In our country, large patches of forests are being cleared for cultivation of crops. The environmental impact of such a practice will lead to
(a) soil erosion
Why is it important to conserve forests? C ONSERVATION O F PLANTS AND ANIMALS 39
To maintain balance in nature/to conserve the natural ecosystem.
Mention any one action that you have undertaken to conserve trees.
Saving paper using recycled paper/donating old books/spreading awareness about harmful effects of deforestation/any other relevant answer.
State whether the following statements are True or False. Correct the false statements.
(i) There can be a wildlife sanctuary within a biosphere reserve.
(ii) Plants of a particular area are collectively termed as fauna.
(iii) Deforestation leads to an increase in the water holding capacity of the soil.
(iv) Bison is an endemic fauna of Pachmarhi Biosphere Reserve.
Can a forest regenerate naturally in a short period of time?
Reforestation can take place naturally by leaving the deforested area undisturbed for a long time. But this process takes a long time in terms of years.
Name the first Reserve Forest of India.
Satpura National Park. SHORT ANSWER QUESTIONS
Why are wildlife sanctuaries important for conservation of plants and animals?
Wildlife sanctuaries are protected areas where human activities like plantation, cultivation, grazing, falling of trees, hunting and poaching are prohibited completely.
Why are endemic organisms in greater danger of becoming extinct?
Endemic organisms are confined to a limited geographical area. They cannot adapt or live outside their natural habitat. Any disturbance to their habitat will adversely affect them.
How are even small animals important in an ecosystem?
Even small organisms are important in an ecosystem because every organism forms a part of a food chain/food web/ecosystem. 128 E XEMPLAR PROBLEMS
A new species X is introduced in a forest. How is it likely to affect the local species of that area?
Introduction of a new species may affect the existence of local species due to competion.
Does soil erosion affect the fertility of soil? How?
Yes. Soil erosion removes the fertile top layer of the soil thereby, exposing the hard rocky lower layers which are less fertile.
What is the unique feature of the biodiversity found in Panchmarhi Biosphere Reserve?
The biodiversity found in Panchmarhi Biosphere Reserve is similar to that found in upper Himalayan peaks and lower Western Ghats.
Mention the aim of Forest (Conservation) Act.
Conservation of natural forests and meeting the basic needs of the people living in or near the forests.
What is biodiversity?
Biodiversity refers to the variety of organisms existing in the Earth, their interrelationships and their relationship with the environment. LONG ANSWER QUESTIONS
Is deforestation associated with global warming? Explain.
Yes. Plants absorb carbon dioxide from the atmosphere for photosynthesis. Deforestation results in decreased number of trees leading to accumulation of carbon dioxide in the atmosphere. Carbon dioxide in the atmosphere traps heat rays reflected by the earth which results in global warming.
How does deforestation lead to frequent floods and droughts?
Deforestation results in decreased water holding capacity of soil. This reduces the infiltration of water into the ground which causes floods. On the other hand, deforestation leads to higher level of carbon dioxide in the atmosphere which causes global warming. Scarcity of trees disturbs the water cycle and may reduce rainfall leading to droughts.
Why should we save paper?
To prevent deforestation, save energy and water needed for manufacturing the paper. Chemicals used to manufacture the paper also cause pollution. ANSWERS 129