Question

Antibody formed of five immunoglobin units /pentamer is

• A. IgG
• B. IgM
• C. IgA
• D. IgD

Answer 1

The correct option is B IgM

Immunoglobulin M (IgM) is one of several forms of the antibody that are produced by vertebrates. IgM is the largest antibody and it is the first antibody to appear in the response to initial exposure to an antigen. On the basis of its sedimentation velocity and appearance in electron micrographs, it was inferred that IgM is mostly a pentamer i.e., a polymer composed of five monomers.

So, the correct answer is 'IgM'.