Answer:
Insulin is composed of an A chain of 21 amino acids and a B chain of 30 amino acids. C-peptide is a peptide composed of 31 amino acids
Step-by-step explanation:
Insulin is composed of an A chain of 21 amino acids and a B chain of 30 amino acids, the chains being held together by two disulfide bonds. A third disulfide bond is present within the A chain. Human insulin differs from porcine insulin by a single amino acid and from beef insulin by three amino acids.