Chapter 37, Problem 20A

Summary Introduction

Introduction:

The proteins of the complement system can be found both in the plasma and as inactive precursors on the surface of cells within the body. Complement proteins, a complex system of more than 30 proteins that act in concert to help eliminate infectious microorganisms.

Answer to Problem 20A

Correct answer:

The correct answer is option (D) all of the above.

Explanation of Solution

Explanation/justification for the correct answer:

Option (D) all of the above. The complement protein system causes the lysis (bursting) of foreign and infected cells, the phagocytosis (ingestion) of foreign particles and cell debris, and the inflammation of surrounding tissue. So, the correct answer is option (D).

Explanation for incorrect answer:

Option (A) enhance phagocytosis. This is not only the role of proteins, found in the plasma, in the immune response. So, this is not the correct answer.

Option (B) activate phagocytes. This is not only the role of proteins, found in the plasma, in the immune response. So, this is not the correct answer.

Option (C) enhance destruction of a pathogen. This is not only the role of proteins, found in the plasma, in the immune response. So, this is not the correct answer.