Chapter 16, Problem 4MCQ

Summary Introduction

Introduction:

The complement system consists of thirty heat-labile proteins from plasma, which are involved in the opsonization of pathogens for assisting the immune responses of the host. The complement proteins are protease in nature, which help to cleave the antigens to neutralize the infectious substances. It is a cascade or a series of proteins (from C1 to C9 and some proteins are indicated as lower cases a) and b). They commences at the time of infection and is termed as the complement activation.

There are three pathways that are involved in the complement system to provide an immune response against the infections. They are as follows: Classical pathway - activates directly by a pathogen or indirectly by antibodies. Lectin and Alternate pathways are the multiplication loop of the two pathways.