This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Unknown
[{'content': 'Which portion of MHC 1 complex forms the component of antigen presenting part : \nSelect and explain. \nA. Between alpha 1 – beta 2 microglobulin, B. Distal part of alpha chain, C. Proximal part of alpha chain, D. Between aS and b2 microglobulin', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Antigen Presenting part of MHC\nMHC I/HLAI :\nClass 1 molecule consists of a three domains of heavy alpha peptide chain (a1 ; a2; a3) which are non-covalently linked to smaller\nβ2 microglobulin peptide.\nThe distal domain (alpha 1 and alpha 2) of MCH 1 have highly variable amino acid sequences and are folded to form a cavity or groove.\nProtein antigens are bound to this groove for presentation to CD8 T cells. MHC II/HLA II :\nMHC II antigens are heterodimer consisting of an alpha and beta chain. Each chain has two domain proximal one is constant and distal one is variable.\nThe two distal domain (alpha 1, beta 1) constitute the antigen binding site, for recognition by CD4 T cells.\nBoth class 1 and class 2 are members of immunoglobulin gene super family.\nMHC III /HLA III\n§ MHC III are heterogenous they include complement components involved in the formation of C3 convertase, heat shock protein and tumor necrosis factor.', 'role': 'assistant'}]