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Q1. Write three damages caused by heavy rains, if the trees are absent.

Solution

(i) If trees are not present, rain hits the ground directly and may flood the area around it. (ii) Heavy rain may also damages the soil. (iii) Roots of trees normally bind the soil together, but in their absence the soil is washed away or eroded.

Q2. How do trees play an important role in regulating the climate?

Solution

Forests have a key role in regulating the climate, because trees by their photosynthesis absorb carbon dioxide from the atmosphere and store carbon as wood and organic matter in the soil.

Q3. Write any three problems encountered if forests disappear.

Solution

(i) If forests disappear, the amount of carbon dioxide in air will increase, resulting in the increase of earth's average temperature. (ii) In the absence of trees and plants, the animals will not get food, protection 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. (Any three points)

Q4. Would we see similar kind of trees and animals in every forest? Why?

Solution

No, the trees and animals would vary in different forests. This is due to the different climatic conditions prevailing in different forests. Hence the types of trees and other plants as well as the types of animals differ from forest to forest.

Q5. Forests must be preserved since they are very important to us. Discuss how forests are important.

Solution

(i) Forests provide us with oxygen.(ii) They protect soil and provide habitat to a large number of animals.(iii) Forests help in bringing good rainfall in neighbouring areas.(iv) They are a source of medicinal plants, timber and many other useful products.

Q6. How are the forests important for herbivores like deer and goat?

Solution

The dense bushes and the tall grass in forests provide the herbivorous animals with the food and shelter. They also protect them from carnivores that live in the forest.

Q7. Name any six trees found in forests.

Solution

Sal, teak, semal, sheesham, neem, palash, fig, khair, amla, bamboo, kachnar (Write any six)

Q8. What is a canopy?

Solution

The covering of large trees that serve as a roof to shelter an area or other plants in forests is called a canopy.

Q9. Name any four useful products other than wood, which we get from forests

Solution

Four useful products which we get from forests are rubber, paper, gum, spices, etc.

Q10. How do forests help to maintain the water table?

Solution

The forests act as a natural absorber of rainwater and allows it to seep into the ground. Thus, it helps to maintain the water table throughout the year.

Q11. Which forms the lowest layer in the forest?

Solution

The herbs form the lowest layer in the forests.

Q12. Name the following: (i) The uppermost branches of the trees in a forest, forming a more or less continuous layer of foliage, appearing like a roof over the other plants in the forest. (ii) The micro-organisms which convert the dead plants and animals to humus. (iii) The dark coloured substance in soil formed by the decomposition of leaves and other plant material by soil microorganisms. (iv) A sequence of organisms in a community, where each member is eaten by another member.

Solution

(i) Canopy (ii) Decomposers (iii) Humus (iv) Food chain

Q13. Discuss how the forest is a 'dynamic living entity'?

Solution

The forest harbours a great variety of plants and this provides greater opportunities for food and habitat for the herbivores. Larger number of herbivores provides 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 full of life and vitality and is a dynamic living entity.

Q14. Write names of any two wooden and non-wooden products each used in our homes, which may have been obtained from forests.

Solution

Wooden items - Plywood, fuel wood, wooden boxes, matchsticks, and furniture. Non-wooden items - Gum, oils, spices, (Any two of each)

Q15. How does forest protect the planet?

Solution

1. Forests create a stable climate and help stabilize the ground and prevent erosion. 2. They protect coasts from waves and ocean swells, they stabilize sand dunes, protect the groundwater and prevent the spreading of desert. 3. Forests are very important for biological diversity.They are the habitat for up to 90% of terrestrial species of animals and plants. 4. The forest provide us with timber, firewood, oils, rubber, medicine.

Q16. What is a crown?

Solution

The branched part of a tree above the stem is called as crown

Q17. What is the difference between a creeper and climber?

Solution

A creeper tends to creep along the soil surface and spread over a long distance while a climber tends to climb up to some support in order to reach the sunlight as it has a weak stem.

Q18. How do the tribals depend on the forest?

Solution

The forest provides the tribals with food, shelter, water and medicines.

Q19. How does deforestation causes flooding?

Solution

The roots in the trees are able to strengthen the soil and prevent erosion. They also absorb some of the water. When the roots are gone from trees after deforestation, there's nothing to strengthen the soil anymore. Hence, the soil slide around and the water is able to build on the surface causing flooding.

Q20. Rohan wrote a food chain the following way: Frog → Eagle → Insects → Grass → Snake The chain is not in the correct order. Help him to write the food chain correctly.

Solution

The correct way of depiction of food chain is: Grass → Insects → Frog → Snake → Eagle

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