Question

The number of amino acids and the molecular weight of human insulin is

• A. 51 amino acids, 58 k.Da.
• B. 41 amino acids, 51 k.Da.
• C. 51 amino acids, 50 k.Da.
• D. 70 amino acids, 55.k.Da.

Answer 1

The correct option is A 51 amino acids, 58 k.Da.

Insulin is a hormone made up of 2 polypeptide chains namely A and B. Each chain is composed of a specific sequence of amino acid residues connected by peptide bonds. In humans, chain A has 21 amino acids, and chain B has 30. Hence, one molecule of insulin contains 51 amino acids. The molecular weight is 58 k.Da. Hence, the correct option is A.