Chapter 14, Problem 1MCQ

Ail example of a nonspecific chemical barrier to infection is/are

1. a. unbroken skin.
2. b. lysozyme in saliva.
3. c. cilia in respiratory tract.
4. d. all of these.

Summary Introduction

Introduction:

The body producesvarious chemical barriers which protect the body from bacteria and other harmful microbes and pathogens. For example, tears contain lysozyme which helps in the degradation of the bacterial cell wall.

Answer to Problem 1MCQ

Correct answer:

An example of a non-specific chemical barrier to infections is lysozyme in saliva. Therefore, option (b) is correct.

Option (b) is given as “lysozyme in saliva”.

Explanation of Solution

Justify reasons for the correct statement:

The non-specific chemical barrier of the body includes secretion of lubricating glands. This barrier protects the body from infections. Lysozyme is present in the saliva, which is responsible for cell wall degradation in bacteria by breaking down the peptidoglycan layer.

Hence, option (b) is correct.

Justify reasons for the incorrect statements:

Option (a) is given as “unbroken skin”.

Unbroken skin is not an example of a non-specific chemical barrier. Hence, it is a wrong answer.

Option (c) is given as “cilia in respiratory tract”.

Cilia in the respiratory tract are not an example of a non-specific chemical barrier. Hence, it is a wrong answer.

Option (d) is given as “all of these”.

Lysozyme in saliva is the non-specific chemical barrier to infection which is produced by the body. Hence, it is a wrong answer.

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

Conclusion

Lysozyme that presentsin the saliva is an example of a non-specific chemical barrier to infection which is produced by the body.