Exercise - Question:

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Que: Answer the following questions.

(i) What is an ecosystem?

(ii) What do you mean by natural environment?

(iii) Which are the major components of the environment?

(iv) Give four examples of human made environment.

(v) What is lithosphere?

(vi) Which are the two major components of biotic environment?

(vii) What is biosphere?

Ans:

1. All plants, animals and human beings depend on their immediate surroundings. They are also interdependent on each other. This relation between the living organisms as well as the relation between the organism and their surroundings form an ecosystem.

2. The natural environment consists of land, water, air, plants and animals. Thus, the natural environment refers to both biotic (plants and animals) and abiotic (land) conditions that exist on the earth.

3. The major components of the environment are—natural (land, air, water, living things), human-made (buildings, parks, bridges, roads, industries, monuments, etc.), and humans (individual, family, community, religion, educational, economic, etc).

4. Four examples of human-made environments—buildings, parks, bridges, and roads.

5. The lithosphere is the solid crust or the hard top layer of the earth. It is made up of rocks and minerals and covered by a thin layer of soil. It is an irregular surface with various landforms such as mountains, plateaus, plains, valleys, etc.

6. Plants and animals are the two major components of a biotic environment,

7. The biosphere is a narrow zone of the earth where land, water, and air interact with each other to support life. Thus, plant and animal kingdom together make biosphere, ie., the living world.

Q2. Tick the correct answer.

(i) Which is not a natural ecosystem?

(a) Desert

(b) Aquarium

(c) Forest

(ii) Which is not a component of human environment?

(a) Land

(b) Religion

(c) Community

(iii) Which is a human made environment?

(a) Mountain

(b) Sea

(c) Road

(iv) Which is a threat to environment?

(a) Growing plant

(b) Growing population

(c) Growing crops

Ans:

(i) (b) Aquarium.

(ii) (a) Land

(iii) (c) Road

(iv) (b) Growing population.

Que: Match the following.

(i) Biosphere                           (a) blanket of air which surrounds the earth

(ii) Atmosphere                       (b) domain of water

(iii) Hydrosphere                     (c) gravitational force of the earth

(iv) Environment                     (d) our surroundings

(e) narrow zone where land water and air interact

Ans:

Column I	Column II
(i) Biosphere	(d) our surronding
(ii) Atmosphere	(a) blanket of air which surrounds the earth
(iii) Hydrosphere	(b) domain of water
(iv) Enviorment	(c) gravitational force of earth

Que: Give reasons.

(i) Man modifies his environment

(ii) Plants and animals depend on each other

Ans:

(i) Man modifies his enviorment to meet his various needs. For example: he clears forests for obtaining land foragriculturew and for making shelter. He extracts minerals from the earth for making various things. He makes dams for producing electricity. These are a few of the ways in which man modifies his enviorment.

(ii) Animals, whether carnivores or herbivores, ultimately depend on plants for their food. Also, plants provide fresh oxygen to animals to breathe in. These keep the enviorment clean and provide shelter to a number of animals. On the other hand, animals provide carbon doxide which plants usde for making their food  

Que: Imagine an ideal environment where you would love to live. Draw the picture of your ideal environment.

Ans: Students are expected to do this activity themselves. However, a sample is given below.