An antibody is produced by the terminally differentiated form of a B cell known as a plasma cell or an antibody secreting cell. It is often represented as a Y shaped molecule and is made up of four separate proteins – two identical heavy chains and two identical light chains. The constant region of the antibody does not change much and is the part of the antibody that carries out the functions of the antibody. It can bind to receptors (FcR) on cells to activate them. The antibody has two arms containing the variable region – so there are two identical binding sites for the antigen.
What is an Antibody?
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