Immunoglobulin G Consists of Four Polypeptides, ________ Heavy Chains, and ________

Question

Immunoglobulin G consists of four polypeptides, ________ heavy chains, and ________ light chains.
A) one / three
B) two / two
C) three / one
D) four / four

Accepted Answer

Immunoglobulin G (IgG) consists of two identical heavy chains and two identical light chains. Each heavy chain has a molecular weight of approximately 50 kDa, while each light chain has a molecular weight of approximately 25 kDa. This gives IgG a total molecular weight of approximately 150-170 kDa. Therefore, choice B (two heavy chains and two light chains) is the correct answer.