An epitope is
A) part of the interferons that penetrate foreign cells.
B) a protein protruding from the surface of B cells.
C) two structurally similar antibodies dissolved in the blood plasma.
D) that part of an antigen that actually binds to an antigen receptor.
E) a mirror image of an antigen.

Question

Quizplus · Accepted Answer

An epitope is the part of an antigen that binds to the antigen receptor on a B or T cell. It is also known as an antigenic determinant. Option A is incorrect as interferons are not composed of epitopes. Option B is incorrect as proteins on the surface of B cells are not epitopes themselves but may display epitopes to facilitate their recognition by other immune cells. Option C is incorrect as antibodies are not epitopes but are molecules that recognize epitopes. Option E is incorrect as a mirror image of an antigen is not an epitope.

An Epitope Is