Explain the structure of antibody.

Explanation

(ii) Structure of an antibody: 1.Antibody is a 'Y' shaped molecule. It has four polypeptide chains, two heavy or H chains and two light or L chains.
(2) The polypeptide chains from a Y'shaped structure through Disulphide bonds. (-S-S-).
3) The region holding arms and stem of antibody is termed as hinge. Each chain of the antibody has two distinct regions., the variable region and the constant region.
4) Variable regions have a paratope which is an antigen binding site. This part of antibody recognizes and binds to specific antigens forming an antigens antibody complex.
5)Antibodies are called bivalent as they carry two antigen binding sites.