<prompt> Human growth hormone has:One polypeptide chain and one intra chaindisulphide bondOne polypeptide chain and two intra chaindisulphide bondTwo polypeptide chains joined by onedisulphide bondTwo polypeptide chains joined by twodisulphide bond  <response>: Ans. B. One polypeptide chain and two intra chaindisulphide bondGrowth hormone or somatotrophin consists of a single polypeptide with a molecular weight of about 21500. It consists of 191 amino acids. There are two disulfide bridges between the adjacent cysteine residues. GH brings about positive nitrogen balance by retaining nitrogen. 