Which of the following is a characteristic or component of an MHC class II molecule? A)1 MHC-encoded polypeptide chain called the heavy chain B)a non-MHC polypeptide associated non-covalently with another subunit C)$\beta$₂-microglobulin D)a heterodimer,with both subunits encoded by MHC alleles E)a heterotrimer,with all three subunits encoded by MHC alleles

Question

Quizplus · Accepted Answer

MHC class II molecules are heterodimers, composed of two different polypeptide chains, alpha and beta. Both subunits are encoded by MHC alleles. Therefore, choice D is the correct answer. Choice A is incorrect because MHC class II molecules are composed of two polypeptide chains, not one. Choice B is incorrect because there is no non-MHC polypeptide associated with MHC class II molecules. Choice C is incorrect because "F1F1F1S1βF1F1F10₂-microglobulin" is not a known component of MHC class II molecules. Choice E is also incorrect because MHC class II molecules are heterodimers, not heterotrimers.

Which of the Following Is a Characteristic or Component of an MHC