NCERT Class 7 Science Chapter 17 - Forest our Lifeline


Chapter 17 - Forest our Lifeline

Question and Answers

Question 1: Explain how animals dwelling in the forest help it grow and regenerate.
Answer:
Animals work as the cleaning agents in the forest. Microorganisms work on dead bodies of plants and animals and degenerate them. Animals also help in pollination which helps in growing a number of plants. Herbivores help the carnivores to grow as they serve as food for them. Thus flora and fauna mutually grow in the forest.

Question 2: Explain how forests prevent floods.
Answer:
Forests can absorb a lot of water. The roots of the trees absorb the water and prevent it from flowing away. Roots of trees also help in percolation of water into the soil. This helps in preventing floods.

Question 3: What are decomposers? Name any two of them. What do they do in the forest?
Answer:
Decomposers are the organisms which feed on the dead bodies of plants and animals. They clean the forests decaying dead bodies and replenishing the nutrients back to the forest soil, e.g. beetles and grubs.

Question 4: Explain the role of forest in maintaining the balance between oxygen and carbon dioxide in the atmosphere.
Answer:
Plants release oxygen in the atmosphere during the process of photosynthesis. This oxygen is inhaled by the animals for respiration. During respiration, they release carbon-dioxide which is absorbed by plants. In this way the oxygen and carbon dioxide cycle goes on. Since forests contain a large number of plants, they help much in this cycle and maintain balance in nature.

Question 5: Explain why there is no waste in a forest.
Answer:
There is no waste in the forest because decomposers convert all the dead bodies of the plants and animals into the humus which gets added to the soil.

Question 6: List five products we get from forests.
Answer:

*We get medicines from forests.
*We get gum from forests.
*We get wood which is used for many purposes like making furniture, paper etc.
*We get food for animals from forests.
*We get sealing wax from forests.

Question 7: Fill in the blank:
(a) The insects, butterflies, honeybees and birds help flowering plants in pollination.
(b) A forest is a purifier of
water, air.
(c) Herbs form the layer in the forest
lowest.
(d) The decaying leaves and animal droppings in a forest enrich the soil as
humus.

Question 8: Why should we worry about the conditions and issues related to forests far from us?
Answer:
We should be worried about deforestation as it would lead to floods, increase in earth’s temperature, decreasing animals habitats and soil erosion. Damage to forests directly or indirectly affects human habitat and environment so it must be a matter of concern among us.

Question 9: Explain why there is a need of variety of animals and plants in a forest.
Answer:
All plants and animals sustain the forest life and also C02 – 02 cycle goes on due to animals and plants. Animals convert the dead and decaying matters into humus and increase the fertility of soil, thus enhancing plant growth. All food chains and food webs need variety of plants and animals.

Question 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, and water table.
 


Answer:

 

Question 11:Which of the following is not a forest product?
(i) Gum
(ii) Plywood
(iii) Sealing wax
(iv) Kerosene
Answer:
(iv) Kerosene

Question 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 dependent 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.

Question 13: Micro-organisms act upon the dead plants to produce
(i) Sand
(ii) Mushrooms
(iii) Humus
(iv) Wood
Answer:
 
(iii) Humus

No comments:

Post a Comment

Also read!

Click on any of the below text for additional links:

Class 6

Class 6 Computer Kips Solutions
Class 6 Gul Mohar English Solutions
→ Class 6 Map Pointing Solutions
Class 6 NCERT Civics Solutions
Class 6 NCERT Geography Solutions
Class 6 NCERT History Solutions
Class 6 NCERT Maths Solutions
Class 6 NCERT Science Solutions

Class 7

Class 7 Computer Kips Solutions
Class 7 Gul Mohar English Solutions
English Grammar Class 7
English Writing Skills Class 7
Class 7 Map Pointing Solutions
Class 7 NCERT Civics Solutions
Class 7 NCERT Civics Notes
Class 7 NCERT Civics Extra Questions
Class 7 NCERT Geography Solutions
Class 7 NCERT Geography Notes
Class 7 NCERT Geography Extra Questions
Class 7 NCERT History Solutions
Class 7 NCERT History Notes
Class 7 NCERT History Extra Questions
Class 7 NCERT Maths Solutions
Class 7 NCERT Science Solutions
Class 7 NCERT Science Notes
Class 7 NCERT Science Extra Questions

Class 8

Class 8 Kips Artificial Intelligence Solutions
Class 8 Gul Mohar English Solutions
English Grammar Class 8
English Writing Skills Class 8
Class 8 Map Pointing Solutions
Class 8 NCERT Civics Solutions
Class 8 NCERT Civics Notes
Class 8 NCERT Civics Extra Questions
Class 8 NCERT Geography Solutions
Class 8 NCERT Geography Notes
Class 8 NCERT Geography Extra Questions
Class 8 NCERT History Solutions
Class 8 NCERT History Notes
Class 8 NCERT History Extra Questions
Class 8 NCERT Maths Solutions
Class 8 NCERT Science Solutions
Class 8 NCERT Science Notes
Class 8 NCERT Science Extra Questions
Class 8 NCERT Science Exemplar
Class 8 NCERT Science MCQs

Class 9

Class 9 Kips Artificial Intelligence Solutions
Class 9 Map Pointing Solutions
Class 9 NCERT Civics Solutions
Class 9 NCERT Geography Solutions
Class 9 NCERT History Solutions
Class 9 NCERT Maths Solutions
Class 9 NCERT Science Solutions

Class 10

Class 10 Kips Artificial Intelligence Solutions
Class 10 NCERT English Solutions
→ Class 10 Map Pointing Solutions
Class 10 NCERT Civics Solutions
Class 10 NCERT Civics Notes
Class 10 NCERT Civics Extra Questions
Class 10 NCERT Geography Solutions
Class 10 NCERT Geography Notes
Class 10 NCERT Geography Extra Questions
Class 10 NCERT History Solutions
→ Class 10 NCERT History Notes
Class 10 NCERT History Extra Questions
Class 10 NCERT Maths Solutions
Class 10 NCERT Science Solutions
Class 10 NCERT Science Notes
Class 10 NCERT Science Extra Questions

Computer Languages

Python Basics

Extra Activities

Extra Activities

Extra Knowledge

Extra Information
General Knowledge
Historical Places in India
Latest technology
Physical Sciences
Facts

• Mathematics quick links
Mathematical Terms
Maths Tricks

Home Top