<prompt> The complementarity-determining regions are-Restricted to light chainsAre in the constant pa of the Ig moleculeBinds to Fc receptorAre concerned in antigen recognition  <response>: In the variable region of the H and L domains, maximum sequence variation is concentrated in a few discrete regions called hyperevariable regions HV . HV regions form the antigen binding site of the antibody molecule which is complementary to the structure of the epitope and are called Complementary Determining Regions CDRs 