Ans. (i) If forests disappear, the amount of carbon dioxide in air will increase, resulting in the increase of earth’s temperature. 

(ii) In the absence of trees and plants, the animals will not get food and shelter. 

(iii) In the absence of trees, the soil will not hold water which will cause floods.

(iv) Deforestation will endanger our life and environment.

 

Ans. Animals help in growing and regenerating forests in many ways. Animals help in dispersing seeds of certain plants. The decaying animal dung also provides nutrients to the seedling of plants. By this number of plants are growing which serve as a food for number of herbivor animals. Herbivores helps the carnivores to grow as they serve as food for them. So, the Flora and fauna grows in the forests.

Also, the animals work as the cleaning agents in the forest micro- organisms work on the dead bodies of plants and animals and regenerate them.

 

Ans. If trees are not thickly grown/ planted on the earth, rain will directly hit the ground and may cause the flood. Also, the heavy rain may damage the soil. Roots of trees and grasses which basically bind the soil together, will be washed away or eroded. The washed soil will get deposited in river and thus reduce the water carrying capacity of rivers and there by become the major cause of floods. Forest can also absorb a lot of water. This also helps in preventing floods. 

 

Ans. The micro-organisms which convert the dead plants and animals to humus are known as decomposers. These micro – organisms play an important role in the forest. The two main decomposers are grubs and beetles. They clean the forests from the decaying dead bodies and replenishes the nutrient back to the forest soil. 

 

Ans. Plants release oxygen through  the process of photosynthesis. The plants help to provide oxygen for animal respiration. They also maintain the balance of oxygen and carbon dioxide in the atmosphere. That is why forests are called green lungs.

Fig. Balance of oxygen and carbon dioxide.

 

Ans. The decomposers decompose the dead organisms. The decomposed matter is absorbed by plants as nutrients. Dead animals are eaten by crows, vultures, insects etc. Thus, there is no waste in a forest.

 

Ans. We get following products from forests: 

(i) Medicine (ii) wood (iii) Gum (iv) Spice (v) Honey.

 

Ans. (a) pollination; (b) water, air; (c) lowest; (d) humus.

 

Ans. We should be worried about deforestation, as it would lead to floods, increase in earth’s temperature, depriving animals of their habitats and soil erosion. 

 

Ans. Variety of animals are necessary for their survival and maintenance of food chain. For example, grass is eaten by insects, which in turn, are eaten by the frog. The frog is consumed by snakes and snakes are eaten by eagles. Thus, it forms a food chain. 

There are so many food chains in the forest. All of these are linked. If any one food chain is disturbed, it effects other food chains. Also, animals convert the death plants and animals into humus and increase the fertility of soil.

 

Ans. Clouds, rain, atmosphere, carbon dioxide, oxygen, plants, animals, soil roots, water table.

Fig.

 

Ans. Kerosene.

 

Ans. (ii) Plants and animals in a forest are not dependent on one another.

 

Ans. (iii) humus.