Consider the following statements regarding the role of the atmosphere: 1. It contains life-giving gases like oxygen for humans and carbon dioxide for plants. 2. It allows harmful ultra-violet rays to reach the earth freely. 3. It acts as a blanket to maintain earth's temperature. Which of the statements given above is/are correct?

The correct option is 1 and 3 only. Explanation The atmosphere is a mixture of gases that surrounds the Earth, held in place by gravity. It plays a critical role in sustaining life and regulating the planet's physical environment. - Statement 1 is Correct: The atmosphere contains gases essential for the survival of life forms. Oxygen is necessary for respiration in humans and animals, while carbon dioxide is vital for plants to perform photosynthesis. - Statement 2 is Incorrect: The atmosphere does not allow harmful ultraviolet (UV) rays to reach the Earth freely. The ozone layer, located primarily in the stratosphere, absorbs the majority of the sun's harmful UV radiation, thereby protecting life on the surface from its damaging effects. - Statement 3 is Correct: The atmosphere acts as a giant insulating blanket. Through the greenhouse effect (primarily due to carbon dioxide and water vapour), it traps terrestrial radiation and prevents the Earth from cooling down excessively at night, thus maintaining a temperature range suitable for life. Key Takeaway: The atmosphere serves as a protective shield against UV radiation and acts as a thermal blanket to moderate Earth's temperature, in addition to providing essential gases like oxygen and carbon dioxide.

NCERT Class 11 Geography — Chapter 1: Composition and Structure of Atmosphere

mcqeasy

Consider the following statements regarding the role of the atmosphere:

It contains life-giving gases like oxygen for humans and carbon dioxide for plants.
It allows harmful ultra-violet rays to reach the earth freely.
It acts as a blanket to maintain earth's temperature.

Which of the statements given above is/are correct?

Official previous-year question

Verified 1 Aug 2026.

Options

A1 and 3 only
B1, 2 and 3
C2 only
D1 and 2 only

Did you get this right?

Solution

The correct option is 1 and 3 only.

Explanation

The atmosphere is a mixture of gases that surrounds the Earth, held in place by gravity. It plays a critical role in sustaining life and regulating the planet's physical environment.

Statement 1 is Correct: The atmosphere contains gases essential for the survival of life forms. Oxygen is necessary for respiration in humans and animals, while carbon dioxide is vital for plants to perform photosynthesis.
Statement 2 is Incorrect: The atmosphere does not allow harmful ultraviolet (UV) rays to reach the Earth freely. The ozone layer, located primarily in the stratosphere, absorbs the majority of the sun's harmful UV radiation, thereby protecting life on the surface from its damaging effects.
Statement 3 is Correct: The atmosphere acts as a giant insulating blanket. Through the greenhouse effect (primarily due to carbon dioxide and water vapour), it traps terrestrial radiation and prevents the Earth from cooling down excessively at night, thus maintaining a temperature range suitable for life.

Key Takeaway: The atmosphere serves as a protective shield against UV radiation and acts as a thermal blanket to moderate Earth's temperature, in addition to providing essential gases like oxygen and carbon dioxide.

Your note

More from Chapter 1: Composition and Structure of Atmosphere

Consider the following statements regarding the composition of the atmosphere: 1. The proportion of gases remains constant up to the highest layers of the atmosphere. 2. Nitrogen is the most abundant gas in the atmosphere. 3. Nitrogen and Oxygen make up the bulk of the atmosphere. Which of the statements given above is/are correct?

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Which of the following is the main reason for the rising volume of carbon dioxide in the atmosphere?

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Consider the following statements regarding water vapour in the atmosphere: 1. It is a variable gas that increases with altitude. 2. It accounts for less than one % of the air by volume in the dry and cold polar regions. 3. It absorbs parts of the insolation from the sun and preserves the earth’s radiated heat. Which of the statements given above is/are correct?

medium

With reference to the composition of the atmosphere, consider the following statements: 1. Oxygen is found in substantial quantities at heights above 120 km from the earth's surface. 2. Carbon dioxide is transparent to incoming solar radiation but opaque to outgoing terrestrial radiation. 3. Carbon dioxide and water vapour are found in uniform concentration up to the exosphere. Which of the statements given above is/are correct?

medium

Which one of the following is the most likely reason for the higher concentration of dust particles in subtropical and temperate regions compared to equatorial regions?

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Keep practising Chapter 1: Composition and Structure of Atmosphere

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The correct option is 1 and 3 only.

Explanation

The atmosphere is a mixture of gases that surrounds the Earth, held in place by gravity. It plays a critical role in sustaining life and regulating the planet's physical environment.

Statement 1 is Correct: The atmosphere contains gases essential for the survival of life forms. Oxygen is necessary for respiration in humans and animals, while carbon dioxide is vital for plants to perform photosynthesis.
Statement 2 is Incorrect: The atmosphere does not allow harmful ultraviolet (UV) rays to reach the Earth freely. The ozone layer, located primarily in the stratosphere, absorbs the majority of the sun's harmful UV radiation, thereby protecting life on the surface from its damaging effects.
Statement 3 is Correct: The atmosphere acts as a giant insulating blanket. Through the greenhouse effect (primarily due to carbon dioxide and water vapour), it traps terrestrial radiation and prevents the Earth from cooling down excessively at night, thus maintaining a temperature range suitable for life.