Chapter 24, Problem 1MCQ

Which of the following is not a major subdivision of the biosphere?

1. a. hydrosphere
2. b. lithosphere
3. c. stratosphere
4. d. atmosphere

Summary Introduction

Introduction:

The integrated functioning of all the ecosystems and interrelating all organisms and abiotic factors is called biosphere. The biodiversity is one of the parts of the biosphere that plays important functions.

Answer to Problem 1MCQ

Correct answer:

The stratosphere is not included in the major subdivisions of the biosphere. Therefore, option (c) is correct.

Option (c) is given as “stratosphere”.

Explanation of Solution

Justify the reasons for the correct statement:

The layer stratosphere is lesser dense and about $1000\text{ times}$ drier as compared to the troposphere. The gases entered into this layer remained for a longer duration due to the least vertical mixing of gases. This layer is warmer due to the absorption of the ultraviolet radiation in this layer. There is no involvement of the stratosphere with the biosphere.

Hence, option (c) is correct.

Justify the reasons for the incorrect statements:

Option (a) is given as “hydrosphere”.

The hydrosphere is the entire collection of water on this planet. The water is included in abiotic components and thus is included in the biosphere. Hence, it is a wrong answer.

Option (b) is given as “lithosphere”.

The lithosphere is the collection of crust and upper mantle. The surface of Earth provides oceans and land that forms the basis of life. Hence, it is a wrong answer.

Option (d) is given as “atmosphere”.

The set of layered gases, in which the abiotic and biotic factors interacts, is termed as the atmosphere. Hence, it is a wrong answer.

Hence, options (a), (b), and (d) are incorrect.

Conclusion

The biosphere does not include stratosphere.