The three-dimensional arrangement/conformation of protein structure is called as tertiary structure. The polypeptide chain undergoes coiling and folding to produce the tertiary structure. It is a compact structure which brings together active amino acids which are otherwise scattered in the chain. It consists of hydrophilic groups attached on the surface of the molecule while the hydrophobic side chains are held towards the interior of the protein molecule. The tertiary structure is maintained by a number of bonds which include hydrogen bonds, disulphide bonds, ionic bonds and hydrophobic bonds.