Question

Which of the following statement(s) is/are incorrect?
(i) Insulin was originally extracted from the pancreas of slaughtered pigs and cattle.
(ii) Animal insulin is identical to human insulin.
(iii) Non-human insulin causes some patients to develop allergies.
(iv) Recombinant insulin is actually obtained from E. coli in bacterial cells.

• A. Only (i) and (ii)
• B. Only (iv)
• C. Only (iii) and (iv)
• D. Only (ii)

Answer 1

The correct option is D Only (ii)

Insulin is a hormone made by the beta cells of Langerhans in the pancreas. Animal insulin is not identical to human insulin. Animal insulin was extracted from the pancreas of cattle and pigs.
The sequence of amino acids (the building blocks that make up the protein) is slightly different in insulin from the different species. Compared to human insulin, porcine (pig) insulin has one different amino acid and bovine (cattle) insulin three different amino acids. These slight differences do not affect the way in which the insulin works inside the human body. Pig insulin is structurally closer to human insulin than is cattle insulin.
These days, animal insulins are made from highly purified pancreas extracts and are marketed as 'natural' insulins.