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Chapter Review:

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• The branches of the tall trees look like a roof over the other plants in the forest that is called a canopy.
• Branchy part of a tree above the stem is known as the crown of the tree.
• The dead plant and animal tissues and convert them into a dark coloured substance called humus.
• The micro-organisms which convert the dead plants and animals to humus are known as decomposers.
• Forests protect the soil from erosion.
• The various components of the forest are interdependent on one
  another.
• Different layers of vegetation provide food and shelter for animals,
  birds and insects.
• Soil helps forests to grow and regenerate.

Exercise 

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1. Explain how animals dwelling in the forest help it grow and regenerate.

Answer:

Animals help in dispersing seeds of certain plants. The decaying animal dung also privides nutrients to the seedling to grow. This is how animals help the forest to grow and regenerate.  

2. Explain how forests prevent floods.

Answer:

Plants act as a natrual observer of rainwater and allow water to seep slowly to recharge ground water. This is how forest help preventing flood.  

3. What are decomposers? Name any two of them. What do they do in the forest?

Answer:

The micro-organism which convert the dead plants and animals to humus are known as decomposers. Bacteria, mushroom, etc. are and provide nutrient to trees.

4. Explain the role of forest in maintaining the balance between oxygen and carbon dioxide in the atmosphere.

Answer:

Plants take in carbon-die- oxide and release oxygen in the process of photosynthesis. Thus, they maintain the balance of oxygen and carbon-dioxide in the atmosphere.

5. Explain why there is no waste in a forest.

Answer:

The decomposers decompose the dead organisms. The decomposed matter is absorbed by plants as nutrients. So, there is no waste in forests.

6. List five products we get from forests? Keywords Canopy Crown Decomposers Seed dispersal Soil erosion Understorey Deforestation Humus Regeneration.

Answer:  

Wood, medicine, spice, fodder. and honey.

 

7. Fill in the blank:

(a) The insects, butterflies, honeybees and birds help flowering plants in .

(b) A forest is a purifier of and .

(c) Herbs form the layer in the forest.

(d) The decaying leaves and animal droppings in a forest enrich the .

Answer:

(a) pollination, (b) water, air (c) ground (d) soil.

8. Why should we worry about the conditions and issues related to forests far from us?

Answer:

Forests are very helpful for us. They clean air, play a vital role in water cycle, provide variious items and so on. So, we should worry about the conditions and issues related to forests far from us.  

9. Explain why there is a need of variety of animals and plants in a forest.

Answer:

(i) Variety of animals are necessary for their survival and maintainance of food chain.

(ii) For example: grass is eaten by insects, which in turn, is eaten by frog.

(iii) The frog is consumed by snakes which is eaten by eagles.Thus, it is made a food chain:

 Grass - insects - frog - snake - eagle

Many food chain can be found in the forest. All food chains are linked. If any one food chain is distrubed, It effects other food chains. Every part of the forest is depandet on each other parts. If we remove one component, say trees, all other components would be affected. 

10. In Fig. 17.15, the artist has forgotten to put the labels and directions on the arrows. Mark the directions on the arrows and label the diagram using the following labels: clouds, rain, atmosphere, carbon dioxide, oxygen, plants, animals, soil, roots, water table.

11. Which of the following is not a forest product?

(i) Gum

(ii) Plywood 

(iii) Sealing wax

(iv) Kerosene

Answer:

(iv) Kerosene

12. Which of the following statements is not correct?

(i) Forests protect the soil from erosion.

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

(iii) Forests influence the climate and water cycle.

(iv) Soil helps forests to grow and regenerate

Answer:

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

13. Micro-organism act upon the dead plants to produce.

(i) Sand

(ii) Mushroom

(iii)Humus

(iv) Wood

Answer:

(iii) Humus.

Additional Question with solution:

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Que: List some animal which live in deeper areas of the forest.

Ans: Boars, bisons, jackals, porcupines, elephants, etc. live in the deeper areas of the forest.

Que: Give the reason behind variations found in the forests of different regions.

Ans: The variation in the type of plants and animals is found in different forests because of the climatic conditions of that particular area.

Que: Are there similar kind of trees in every forests?

Ans: No, due to different climatic conditions, there are variations in the type of trees and other plants. From forest to forest.

Que: State the consequence when one food chain is disturbed in an ecosvstem.

Ans: Since, all food chains are interlinked disturbance in one food chain will affect the other food chain in a forest.

Que: What is a canopy?

Ans: The uppermost branches and leaves of tall trees act like a roof over forest ground, this is called a canopy.

Que: While going inside a forest, it becomes darker. why?

Ans: In a forest, big trees, shrubs and plants are found. They trap solar radiation for photosynthesis.

Que: give names of any four birds which you expect to see in a forest.

Ans: The four birds which we expect to see in a forest are jungle crow, hornbill, myna and koel.

Que: Draw any simple food chain in a pond.

Ans: A typical food chain in a pond is 

 Algae -------> small fishes ---------> Large fishes

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

Ans: Four useful products other than wood which we get from forests are gum, spices, fodder for animals and medicinal plants.

Que: Deforestation may lead to floods. Why?

Ans: Deforestation leads to floods as lesser number of trees will be available due to deforestation. In the absence of trees, the soil will hold water leading to floods.

Que: All the needs of animals living in a forest are fulfilled. Justify this statements in a few sentences.

Ans: Forest provides homae (shelter), food and water to the animals living there. Thus, all the needs of animals living in a forest are fulfilled.

Que: Forests are valuable resources. Explain.

Ans: Forest products play vital role in socio - economic development. We get food, fire wood, fibre, construction material, industrial products and products of medicinal importance. It is also the home of diverse wildlife which maintains the ecosystem. Thus, forests are valuable resources.

Additional Question with solution:

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Que: List some animals which live in deeper areas of the forest.

Ans: Boars, bisons, jackals, porcupines, elephants, etc. live in the deeper areas of the forest.

Que: Paheli while moving in a forest observed that there was no noise pollution, through lots of heavy vehicles were passing from the nearby highway. Explain why.

Ans: Paheli observed that there is noise pollution in a forest even though there are lots of heavy vehicles were passing from the nearby highway. It is because trees present in the forest absorb the noise.

Que: Give the reason behind variations found in the forests of different regions.

Ans: The variation in the type of plants and animals is found in different forest because of the climatic conditions of that particular area.

Que: Are there similar kind of trees in every forests?

Ans: No, due to different climatic conditions, there are variations in the types of trees and other plants. From forest to forest.

Que: State the consequence when one food chain is distured in an ecosystem.

Ans: Since, all food chains are interlinked disturbance in one food chain will affect the other food chain in a forest.

Que: What is a canopy?

Ans: The uppermost branches and leaves of tall trees act like a root over forest ground, this is called a canopy.

Que: While going inside a forest, it becomes darker. Why?

Ans: In a forest, big trees, shrubs and other plants are found. They trap solar radiation for photosynthesis.

So, the sunlight does not reach at the forest floor, thus making it dark.

Que: A bunch of seedling were seen sprouting on a heap of animal dropping in a forest. How do you think is the seeding benefited from the animal dung? 

Ans: The seeding was being benefited from the animal dung as the decaying animal dung provided nutrients to the growing seeding.

Que: forest are called green lungs. Why?

Ans: The forest  provide us oxygen to breathe. If we rapidly cutting down forests means we are cutting down the oxygen supply to us. that is why are called green lungs.