Q.2 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

(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 proinsulin molecule, C-peptide is removed leaving behind A and B chains which bound together by disulphide bonds to constitute a insulin molecule.