EXERCISE
I. Objective Type Questions
A. Choose the correct answer.
1. ‘Environer’ is a ………. word
(a) hindi
(b) Greek
(c) French ✓
(d) English
2. Which of the following is included in the natural environment?
(a) air
(b) land
(c) water
(d) all of these ✓
3. Lithos refers to ……….
(a) water
(b) rocks ✓
(c) moisture
(d) gases
4. Which of the following forces hold the atmosphere around the earth?
(a) Gravitational force ✓
(b) Neutron force
(c) Coriolis force
(d) None of these
5. The elevation of any landform is measured by the
(a) plains
(b) plateaus
(c) ocean floor ✓
(d) none of these
6. In which of the following zones the land, air and twater meet to support life 7 mo
(a) Hydrosphere
(b) Biosphere ✓
(c) Atmosphere
(d) Lithosphere
7. Which one of the following systems is an artificial ecosystem?
(a) Aquarium ✓
(b) Rainforest
(c) Ponds
(d) Desert
8. Which one of the following factors is a threat to environment?
(a) Growing industries ✓
(b) Growing crops
(c) Growing population
(d) None of these
B. Mark the option that matches Column A with Column B.
| Column A | Column B |
| 1. Global warming2. Rainforests3. Aquarium4. Human5. Land | (i) Artificial ecosystem(ii) Rising temperature(iii) Natural environment(iv) Abiotic environment(v) Biotic environment |
(a) 1.-(i), 2.-(iii), 3.-(v), 4.-(i), 5.-(iv)
(b) 1.-(iii), 2.-(ii), 3.-(v), 4.-(i), 5.-(iv)
(c) 1.-(ii), 2. -(iii), 3. -(i), 4. (v), 5.-(iv) ✓
(d) 1.-(i), 2.-(iii), 3.-(i), 4.-(v), 5.-(iv)
C. State True or False
1. Aquarium is an example of artificial ecosystem. [True]
2. Roads are example of natural environment. [False]
3. Plants and animals come under Abiotic environment. [False]
4. Lithosphere consists of different types of landmasses. [True]
5. Humans modify environment for their needs. [True]
D. Assertion Reason
For question numbers 1 to 4, two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (bi, t and (d) as given below:
(a) Both Assertion and Reason are true and Reason is the correct explanation of the Assertion.
(b) Both Assertion and Reason are true but Reason is not the correct explanation of the Assertion.
(c) Assertion is true but Reason is false.
(d) Assertion is false but Reason is true.
1. Assertion (A): Lithosphere consists of mountains and plateaus.
Reason (R): Atmosphere consists of many gases and water vapour.
Answer: (b) Both statements are true, but the Reason does not explain the Assertion.
2. Assertion (A): Human modify the environment.
Reason (R): They do this to satisfy their needs and make lite easy.
Answer: (a) Both are true, and the Reason is the correct explanation of the Assertion.
3. Assertion (A): Lakes and rivers are parts of Hydrosphere.
Reason (R): Mountains and plateaus are parts of Atmosphere.
Answer: (c) Assertion is true, but Reason is false (Mountains and plateaus belong to the Lithosphere, not Atmosphere).
4. Assertion (A): Plants and animals are not dependent on each other.
Reason (R): Human beings are dependent on plants and animals.
Answer: (d) Assertion is false, but Reason is true (Plants and animals are interdependent).
II. SHORT ANSWER TYPE QUESTIONS
1. Differentiate between the natural and the man-made environment
Answer:
| Natural Environment | Man-made Environment |
| Includes all naturally occurring components like air, water, land, plants, and animals. | Includes elements created or modified by humans such as buildings, parks, roads, and industries. |
| Not created or altered by humans. | Entirely a result of human activity. |
| Examples: Mountains, rivers, forests. | Examples: Cities, vehicles, bridges. |
2. Define the term atmosphere Write in short how the atmosphere is useful for us.
Answer: The atmosphere is the thin layer of gases that surrounds the Earth. It includes gases like nitrogen, oxygen, carbon dioxide, and water vapour.
Importance of Atmosphere:
3. What do you know about the human environment
Answer: The human environment refers to the surroundings created or influenced by human beings. It includes all human-made structures like houses, roads, schools, industries, and cities. It also involves social, cultural, political, and economic activities of humans. Human beings are considered a part of the biotic component and they shape and modify the environment to suit their needs.
4. Man modifies his environment Give reasons to support this statement
Answer: Yes, man modifies his environment to make life more comfortable and efficient.
Reasons:
III. LONG ANSWER TYPE QUESTIONS
1. Discuss how the plants and animals are interdependent on each other.
Answer: Plants and animals are closely interdependent for their survival and well-being.
Plants produce oxygen during photosynthesis, which is essential for animals to breathe. In return, animals exhale carbon dioxide, which is used by plants to carry out photosynthesis.
Plants are producers, meaning they make their own food. Herbivores (plant-eating animals) depend on plants for their food. Carnivores, in turn, depend on herbivores. Thus, animals indirectly depend on plants for their food, and the balance of nature is maintained.
Trees and plants provide shelter to many animals such as birds, insects, and monkeys.
Insects, birds, and animals help in pollinating flowers and dispersing seeds, which helps plants to reproduce and grow in new areas.
When animals die, their bodies decompose and become part of the soil, enriching it with nutrients. This helps plants grow better.
2. Define the term ecosystem. How is it useful for human beings
Answer: An ecosystem is a community of living organisms (plants, animals, and microbes) interacting with each other and with their non-living surroundings (air, water, soil, sunlight) in a particular area.
Examples: Forests, ponds, deserts, grasslands, and even aquariums.
Usefulness of Ecosystem for Human Beings:
3. Human activities are adversely affecting our environment. Do you agree with this statertrot? Why and how?
Answer: Yes, I strongly agree that human activities are harming the environment. Due to increasing population and technological advancement, people are using natural resources carelessly and polluting the environment.
Reasons and Examples:
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