<prompt> Metal required for polymerization of insulin is:CopperChromiumCobaltZinc  <response>: Ans. D. ZincInsulin is produced by b-cells of pancreas and consists of 51 amino acids. Chain A has 21 amino acids and chain B has 30 amino acids. Both are held together by two inter chain disulfide bridges. In the b-cells, insulin also called proinsulin combines with zinc to form complexes. It is stored in this form in the granules of the cytosol. 