CBSE Class 7 Science Forests Our Lifeline Worksheet

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.

2- State True Or False.

(i) Animals provide nutrients to plants. (True)
(ii) The forest cover in India is only 15% of its total land area. (False)
(iii) Crown is the shape of the trees. (True)
(iv) Deforestation is cutting of trees to clear area for building houses and farming. (True)
(v) Deforestation takes place due to overgrazing. (True)

3- Match The Column ‘A’ With Column ‘B’.
Column A                                            Column B
(i) Plants                                         (a) Forests
(ii) A renewable natural source         (b) Practice of planting trees on a large scale
(iii) Afforestation                              (c) Deforestation
(iv) Removal of plants                      (d) Producers

4. Choose The Correct Answer.

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

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

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

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

5- Very Short Answer Type Questions.

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

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

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

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.

6- 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. 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. 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.

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

7- Long Answer Type Questions.

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.

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. 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. 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. 

More Question

I Fill in the blanks:

1. Decomposers convert dead plants and animals into __________________.

2. Tall trees which look like roof over other plants in the forest is called ______________.

3. The various components of the forests are ___________ on another.

4. Forests are the ___________ for the forest dwelling communities.

5. ______________ help forest to grow and regenerate.

6. ______________ forms the uppermost layer in the forest.

II State whether True or False:

1. The different horizontal layers in the forest are known as under storeys.

2. Forest help in causing floods.

3. Forest are called green lungs.

4. The type of animals remain same from forest to forest.

5. Deforestation will endanger our life and environment.

6. Forest is a dynamic living entity.

III Name the following:

1. The branchy part of a tree above the stem.

2. Two forest products.

3. The lowest layer of vegetation in a forest.

IV Define:

1. Forest.

2. Deforestation.

3. Canopy.

4. Crown

1. Define the following:

a) Food chain b) Food web c) Extinct d) Deforestation e) Delhi ridge

2. Give reasons for the following:

a) It is impossible to replace a destroyed forest by planting trees elsewhere.

b) Interdependency of plants and animals in forest is a danger alongwith beauty.

c) Delhi Ridge is called “Green Lung” of Delhi.

3 . Draw the following:

a) The environmental role of forest.

b) A food chain and a food web from forest ecosystem.

4. Name the following:

a) The oldest mountain range in country.

b) Two extinct species.

c) Release of water vapour by trees.

d) Delhi lies in the triangle formed by ridge and the river _____________________.

e) Two trees which yield gum.

f) Four medicinal plants.

g) Five forest products.

h) Two trees used for making paper.

5. Answer the following:

a) Write the uses of quinine, neem, amla, tulsi and morphine.

b) List the disadvantages of deforestation.

c) What happens when animals are deprived of food and shelter?

d) What are the causes of shrinking of Delhi Ridge?

e) Explain the interdependency of forest and the organisms in the forest.

f) List the importance of Delhi ridge.

g) How forests help in:

i. Checking pollutions

ii. Preventing soil erosion

iii. Maintaining temperature

iv. To recharge ground water

I. FILL IN THE BLANKS

1. Forest are the _________________ for the forest dwelling communities.

2. The various components of the forests are __________________ on one another.

3. Forest protect the ____________________ from erosion.

4. Decomposers convert dead plants and animals into __________________.

5. __________________ forms the uppermost layer in the forest.

II. WRITE TRUE OR FALSE

1. We get various useful products from the forests surrounding us.

2. Forests must be cleared to make the human life safe and comfortable.

3. The different horizontal layers in the forest are known as understoreys.

4. Forests are called green lungs.

5. Forests influence climate water cycle and air quality.

6. Forests help in causing floods.

7. Forest is a dynamic living entity.

III. NAME THE FOLLOWING

1. Two forest products.

2. The lowest layer of vegetation in a forest.

3. Sequence that represent the series of eating and being eaten.

4. The branchy part of a tree above the stem.

IV. DEFINE

1. Forest

2. Deforestation

3. Canopy

4. Crown

1.Forests provide us many useful items like-
(A) Wood.
(B) Fodder for animals.
(C) Spices and medicines.
(D) All of these.

2.Plants and trees grow in forests because-
(A) The trees produce enough seeds.
(B) The forest floor provides favorable conditions for the seeds to germinate.
(C) Germination of seeds leads to development of seedlings and saplings.
(D) All of these in same sequence.

3.Branches of tall trees looking like a roof over the other plants in the forests are known as-
(A) Canopy.
(B) Root.
(C) Shoot.
(D) Crown.

4.Under storeys are the-
(A) Roots of plants.
(B) Stems of plants.
(C) Different horizontal layers formed by the crowns of different types and sizes of plants and trees.
(D) None of these.

5.The under storeys have-
(A) Giant and tall trees constituting the top layer.
(B) Shrubs and tall grasses forming the middle layer.
(C) Herbs forming the lowest layer.
(D) All of these.

6.The forest floor is usually covered with a layer of-
(A) Dead animals.
(B) Dead and decaying leaves, fruits, seeds, twigs and small herbs.
(C) Water.
(D) Green grass.

7.The decaying matter is normally-
(A) Spongy.
(B) Warm.
(C) Moist.
(D) Warm and moist with a spongy feel to walk on.

8.There are many food chains operating in a forest. Each food chain tells-
(A) The eating habits of an organism.
(B) Which organism feeds on which organism.
(C) Habitat of an organism.
(D) None of these.

9.Plants, soil and decomposers in a forest are _________________ .
(A) Inter-related.
(B) Dependent on each other.
(C) Inter-related and dependent on each other.
(D) Adapted to share the same food.

10.Decomposers are those organisms that-
(A) Feed on dead and decaying matter.
(B) Feed on living plants.
(C) Feed on living animals.
(D) Convert dead plant and animal tissues into humus.

11.Nutrients are received-
(A) From the humus, obtained from the dead plants and animals.
(B) From humus present in soil.
(C) By the roots of living plants from the soil.
(D) All of these

12.Water in liquid state evaporates to vapour state; vapours condense back to liquid state in form of rains. Plants help to maintain the water cycle by-
(A) Retaining water.
(B) Not allowing water to evaporate.
(C) Absorbing water from the soil through their roots and releasing water vapours into the air by evaporation through the leaves.
(D) All of these.

13.Forest is a dynamic living entity and it keeps on growing as-
(A) Animals disperse seeds of certain plants.
(B) Decaying animal dung also provides nutrients to seedlingsfor theirgrowth.
(C) Wide variety of animals help the forest to regenerate and grow.
(D) All of these.

14.Forests serve as green lungs and water purifying systems in nature. Do you agree?
(A) Yes.
(B) No.
(C) Can't say.
(D) May be.

15.Visitors are advised to keep quiet in forests because-
(A) Animals will come to know about them.
(B) Noise could disturb the animals living in the forest.
(C) Animals get scared.
(D) All of these.

16.One is not able to see land while viewing the forest from a height because-
(A) It is overcast.
(B) Land is not there.
(C) Different treetops have formed a green cover over the land.
(D) Mountains obstruct the view.

17.We feel quite fresh and happy in forests because-
(A) The environment is peaceful.
(B) A cool breeze blows.
(C) There is darkness.
(D) Both (a) and (b).

18.Animals warn their fellow animals of forests about the intruders-
(A) By visiting them personally.
(B) By making unusual sounds.
(C) By making unusual faces.
(D) By throwing fruits or other articles.

19.Thereis large number of big trees in forests. But we can also find-
(A) Shrubs.
(B) Herbs.
(C) Grasses.
(D) All of these.

20.Forests are called green lungs because-
(A) Plants release oxygen through the process of photosynthesis.
(B) Plants provide oxygen for animal respiration.
(C) They maintain balance of oxygen and carbon dioxide in the atmosphere.
(D) All of these.

21.Give some examples of plants that are found in forests?

22.Branchy part above the stem of a tree is known as-
(A) Canopy.
(B) Crown.
(C) Shoot.
(D) Root.

23.Forests are habitat to many-
(A) Animals and plants.
(B) Birds.
(C) Humans.
(D) Pets.

24.What is crown of the tree?

25.What is the difference between canopy and understorey?
(A) Understorey is present below the canopy.
(B) Canopy is present below the understorey.
(C) There is no difference. Both canopy and understorey lie at the same level.
(D) Canopy is the other name of understorey.

26.In forests, __________ help in maintaining the supply of nutrients for growing plants.
(A) producers
(B) decomposers
(C) animals
(D) carnivores

27.The temperature increases due to-
(A) Decrease in the amount of CO²
(B) Increase in the amount of CO2.
(C) Increase in the amount of O2.
(D) Increase in the amount of sunlight.

28.Name two animals that live in the deeper forests?

<2M>

29.Explain the role of forests in maintaining the balance between oxygen and carbon dioxide in the atmosphere

30.What would happen if it rains heavily and trees are not there?

31.How do the forest officers recognise the presence of some animals in the forest?

32.Different forests have different types of trees, plants and animals due to different climatic conditions. Do you agree with this statement? Give reasons for your answer.

33.How are nutrients recycled?

<3M>

34.Why do heavy rains in forests not cause flood?

35.What is food chain? Give two examles

36.What is the effect of deforestation on water cycle?

37.List some human activities that lead to the destruction of forests.

38.What are the advantages of animal droppings?

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

<5M>

40.Why is forest known as a "Dynamic living entity"?

41.What is forest? What would happen if forest will disappear from earth?(4points)

42.What is the importance of forest in our life?