Which among the following is incorrect about the insulin ?

The C peptide is present in the mature insulin and is not removed during maturation into insulin.

The correct answer is Option (4) - The C peptide is present in the mature insulin and is not removed during maturation into insulin.

Insulin used for diabetes was earlier extracted from pancreas of slaughtered cattle and pigs.Insulin consists of two short polypeptide chains: chain A and chain B, that are linked together by disulphide bridges. In mammals, including humans, insulin is synthesised as a pro-hormone (like a pro-enzyme, the pro-hormone also needs to be processed before it becomes a fully mature and functional hormone) which contains an extra stretch called the C peptide. This C peptide is not present in the mature insulin and is removed during maturation into insulin.