Question

The figure given below shows an antibody molecule. Name the parts A, B and C.

• A. A-Antigen binding site, B-Heavy chain, C-Light chain
• B. A-Antibody binding site, B-Light chain, C-Heavy chain
• C. A-Antigen binding site, B-Short chain, C-Long chain
• D. A-Antibody binding site, B-Long chain, C-Short chain
  

Answer 1

The correct option is A A-Antigen binding site, B-Heavy chain, C-Light chain

A-Antigen binding site, B-Heavy chain, C-Light chain

Each antibody has a Y shaped structure made up of two short light weight peptide chains (C) and two long heavy weight peptide chains (B) joined to each other by disulfide bonds.

Each chain in the antibody has both constant and variable regions. The amino acid sequence and conformation of the variable region keeps changing according to the shape of the antigen that needs to be destroyed. There is a unique antigen binding site in each antibody that is compatible with specific antigens. This site includes the variable regions of both the heavy and the light chain.