Q18. Explain the importance of forest.
Why is it important to conserve forest?
are very important to us. They provide us with oxygen. They protect
soil and provide habitat to a large number of animals. They help in bringing
good rainfall in neighbouring areas. They are a source of medicinal plants,
timber and many other useful products.
Q19. What are decomposers? Name any two of them. What do they do
in the forest?
micro-organisms which convert the dead plants and animals to humus are known as
decomposers. Decomposers break down dead plant and animal matter so the
nutrients in them are recycled back into the ecosystem to be used again. Examples
of decomposers include bacteria, fungi etc.
Q20. Explain the role of forest in maintaining the balance
between oxygen and carbon dioxide in the atmosphere.
Ans. Plants release oxygen through the process of
photosynthesis. The plants help to provide oxygen for animal respiration.
Plants use carbon dioxide released by animals. Thus, they maintain the balance
of oxygen and carbon dioxide in the atmosphere.
Q21. Why does deforestation increase carbon dioxide in the
Plants release oxygen through the process of photosynthesis. The plants help to
provide oxygen for animal respiration. Plants use carbon dioxide released by
animals. Thus, they maintain the balance of oxygen and carbon dioxide in the
atmosphere. If forests disappear, the amount of carbon dioxide in air will
increase, resulting in the increase of earth’s temperature.
Q22. Explain why there is no waste in a forest.
The decomposers convert dead plants and animals to humus. The presence of humus
ensures that the nutrients of the dead plants and animals are released into the
soil. From there, these nutrients are again absorbed by the roots of the living
dead animals become food for vultures, crows, jackals and insects. In
this way, the nutrients are cycled. So, nothing goes waste in a forest.
Q23. Explain why forest is called “the dynamic living entity”?
By harbouring greater variety of plants, the forest provides greater
opportunities for food and habitat for the herbivores. Larger number of
herbivores means increased availability of food for a variety of carnivores.
The wide variety of animals helps the forest to regenerate and grow. Decomposers
help in maintaining the supply of nutrients to the growing plants in the forest.
Therefore, the forest is a ‘dynamic living entity’ — full of life and vitality.”
Q24. Explain how forests prevent floods.
Forest also acts as a natural absorber of rainwater and allows it to seep. It
helps maintain the water table throughout the year. Forests not only help in
controlling floods but also help maintain the flow of water in the streams so
that we get a steady supply of water. On the other hand, if trees are not
present, rain hits the ground directly and may flood the area around it. Heavy
rain may also damage the soil. Roots of trees normally bind the soil together,
but in their absence the soil is washed away or eroded.
Q25. Explain how forest affects our food chain.
Every part of the forest is dependent on the other parts.
What difference will it make if we cut trees for a factory?
All animals whether herbivores or carnivores, depend ultimately on plants for
food. Organisms which feed on plants often get eaten by other organisms, and so
on. For example, grass is eaten by insects, which in turn, is taken by the frog.
The frog is consumed by snakes. This is said to form a food chain: Grass→
eagle. Many food chains can be found in the forest. All food chains are linked.
If anyone food chain is disturbed, it affects other food chains. Every part of
the forest is dependent on the other parts.
Q26. Why should we worry about the conditions and issues related
to forests far from us?
What would happen if forests disappear?
should worry about the conditions and issues related to forests far from us
If forests disappear, the amount of carbon
dioxide in air will increase, resulting in the increase of earth’s temperature.
In the absence of trees and plants, the
animals will not get food and shelter.
In the absence of trees, the soil will not
hold water, which will cause floods.
Deforestation will endanger our life and