Question

Comment upon human insulin.

Hint:

Recombinant DNA technology made large-scale production of human insulin possible.

Answer 1

Step 1: About human insulin.
Human insulin is a peptide hormone secreted by the \(\beta\)-cells of the pancreas (Islets of Langerhans). It regulates blood glucose levels by promoting the uptake of glucose into cells and converting it into glycogen.

Step 2: Structure.
Insulin is made up of two polypeptide chains – chain A (21 amino acids) and chain B (30 amino acids), linked together by disulfide bonds.

Step 3: Medical significance.
- In diabetic patients, the body either does not produce enough insulin (Type 1 diabetes) or cannot effectively use it (Type 2 diabetes).
- Recombinant DNA technology is used to produce human insulin artificially (Humulin) in bacteria like E. coli, which is used for treatment.

Final Answer:
\[ \boxed{\text{Human insulin is a peptide hormone that regulates blood sugar, and recombinant insulin is used to treat diabetes.}} \]