CBSE Class 7 Science Forests Our Lifeline VBQs

Question 1- Fill In The Blanks.

(i) Animals help plants in the dispersal of seeds.

(ii) Oxygen gas is released by plants during photosynthesis.

(iii) Deforestation and forest fires are the major threats to forests.

(iv) Large scale planting of tree saplings is called Afforestation.

State True Or False.

Question. Animals provide nutrients to plants. (True)
Answer : True

Question. Crown is the shape of the trees. (True)
Answer : True

Question. Deforestation takes place due to overgrazing. (True)
Answer : True

Question. The forest cover in India is only 15% of its total land area. (False)
Answer : False

Question. Deforestation is cutting of trees to clear area for building houses and farming. (True)
Answer : True

Match The Column ‘A’ With Column ‘B’.

Answer : (i) - (d), (ii) - (a), (iii) - (b), (iv) - (c)

Choose The Correct Answer.

Question. Bacteria and fungi act as:
a) Decomposers
b) Herbivores
c) Omnivores
d) Carnivores
Answer : A

Question. Which of the following is not a forest product:
a) Plywood
b) Sealing wax
c) Kerosene
d) Gum
Answer : C

Question. Microorganisms act upon the dead organisms to produce:
a) Humus
b) Wood
c) Sand
d) All of these
Answer : A

Question. A food chain includes:
a) Producers and Herbivores
b) Producers and Carnivores
c) Producers and Decomposers
d) Producers, Herbivores and Carnivores
Answer : D

Very Short Answer Type Questions.

Question. What is afforestation?
Answer : Large scale planting of tree saplings is called Afforestation.

Question. How much land area on the earth is covered with forest?
Answer : Approximately one-third.

Question. What causes global warming?
Answer : Due to deforestation and pollution green house effect increases, which cause gradually increase in earth’s average temperature. This is known as global warming.

Question. What is an ecosystem?
Answer : Living beings and their environment togetsher form an ecosystem.

Short Answer Type Questions.

Question. In terms of food chain, discuss the interdependence of plants and animals.
Answer : Plants produce food by photosynthesis, this food is used by herbivores. Carnivores eat herbivores and make food chain. Animals and decomposers provide nutrients to plants.

Question. Explain how forests prevent floods?
Answer : Plants in the forests will not allow the rainwater to fall directly on earth and these plants also hold water which helps in preventing floods.

Question. How do forests help in conservation of soil?
Answer : Roots of plants hold the soil and prevent soil erosion. Forests also make soil nutrient rich.

Question. List five products we get from forests.
Answer : i) Medicines, ii) Spices, iii) Wood, iv) Paper, v) Gum.

Question. Give two examples which show that plants depend on animals.
Answer : (1) Plants use carbon dioxide gas for photosynthesis, exhaled by animals.
(2) Animals help expansion of forest by helping in pollination and seeds dispersal.
(3) Animals provide nutrients to plants.

Long Answer Type Questions.

Question. Describe how animals depend on plants.
Answer : (1) Animals get food from plants.
(2) Animals get oxygen gas for respiration from atmosphere, which is released by plants in photosynthesis.
(3) Animals get shelter under trees.
(4) Many predators capture their prey by hiding in trees.

Question. Enlist various uses of forests.
Answer : Uses of forests:
(1) Forests prevent soil erosion and floods.
(2) We get fuel-wood, wood for paper and timber from forests.
(3) Forests help to bring rains.
(4) Forests balance amount of oxygen and carbon dioxide gases in atmosphere.
(5) Forests check global warming.
(6) We get many products like medicines, spices, resins, latex etc. from forests.

Question. What measures can be taken for the conservation of forests?
Answer :(1) Use of wood as fuel should be discouraged.
(2) Cutting of trees for other purposes should be matched with planting more trees.
(3) Forest fires should be controlled.
(4) Overgrazing and illegal cutting should be controlled.
(5) Steps should be taken for planting trees on large scale i.e. afforestation.

Question. What is deforestation? Explain various causes responsible for deforestation.
Answer : The large scale felling or cutting of trees is known as deforestation. Causes:
(1) Increased demand of fuel-wood, wood for paper and timber.
(2) Increased demand of land for industries, houses, roads etc.
(3) Overgrazing by cattle and sheep.
(4) Increased mining activity.
(5) Forest fires.