question_answer 13)

  C-peptide of human insulin is (a) a part of mature insulin molecule                       (b) Responsible for the formation of disulphide bridges (c) removed during maturation of pro-insulin to insulin (d) responsible for its biological activity

Answer:

                  (c) The connecting peptide or C-peptide is a short protein containing 31 amino acids. It connects the A and B chain of proinsulin molecule. After the processing of proinsulinmolecule, C-peptide is removed leaving behind A and B chains which bound together by disulphide bonds to constitute a insulin molecule.