Site MapHelpFeedbackActivation of Complement
Activation of Complement

What is Complement? Complement is a group of molecules produced by the body to attack microbes and other foreign substances. The complement molecules are a group of about 30 serum proteins that can cause lysis of invading cells. These proteins are inactive until activated by the immune system. Complement proteins are also involved in the inflammatory response and in the more specific responses to invaders taken in acquired defense. Complement can amplify inflammation by stimulating the release of histamine. Compliment can also attract cells to infection sites and damage the cell wall and membrane of microbes so they can be attacked more readily.

View the animation below, then complete the quiz to test your knowledge of the concept.






1All of the following processes can be activated by complement except
A)inflammation
B)antibody production
C)cytolysis
D)opsonization
E)none of the above



2Opsonization is
A)a membrane attack complex lysing a bacterium by making a hole in its membrane
B)when complement causes inflammation to occur
C)when the nine complement factors cascade in order
D)coating of a bacterium with antibody to make it more susceptible to phagocytosis



3Complement factors C5b+C6+C7+C8 make up a membrane attack complex that results in
A)enhanced phagocytosis
B)opsonization
C)cytolysis
D)all of the above



4Complement factors are named in the order in which they function.
A)True
B)False



5In the classical pathway of complement activation, complement attaches to an antigen-antibody complex.
A)True
B)False







Animation Quiz SiteOnline Learning Center

Home > Biology 1 > Chapter 43 > Activation of Complement