Chapter 36, Problem 1FIB

Summary Introduction

Introduction:

The body mechanisms that protect against microbial infections are of three types: external barrier, innate and adaptive immune response. Together, these mechanisms protect the body against the infections and any invading infectious agent.

Answer to Problem 1FIB

Correct answer:

External defenses against microbial invasion include the skin and the mucous membranes that line the digestive, respiratory and urogenital tracts.

Explanation of Solution

The external barrier is the nonspecific barrier that prevents the entrance of pathogens and infectious agents by providing the first line of defense to the body. The pathogens of any type will not be able to penetrate the body till these barriers remain intact. Skin and mucous membrane that lines digestive, respiratory, reproductive and urinary system create a wall against the entry of pathogens.

Conclusion

External barriers are the nonspecific type of immune response which includes skin, and mucous membrane that lines digestive, respiratory, reproductive and urinary system.