Question

Insulin by chemical nature is
A. Carbohydrate
B. Protein
C. Steroid
D. Lipid

Answer 1

Hint: Insulin is a hormone made by the pancreas, a gland present behind the stomach. It allows your body to utilize glucose for energy. Glucose is present in humans as sugar. When glucose enters your bloodstream, insulin causes cells throughout your body to absorb the sugar and use it for energy. Insulin also helps in balancing your blood glucose levels.

Complete answer:
• Insulin by chemical nature is protein.
• The ultrastructure of proteins is as follows:
• Frederick Sanger discovered the sequence first.
• It contains two polypeptide chains.
• The first chain is made up of 21 Amino Acid. The second chain contains 30 Amino acids and makes a total of 51 Amino acids.
• The first chain is called the Phenyl-alanine chain, whereas the second chain is the Glycine chain.
• The chains are connected to each other by Di-sulphide bonds having S --S linkage.
• A total of three Di-sulphide linkages present two inter-chain linkages and one intra-chain linkage.

Hence, the correct answer is option (B).

Additional information:
The deficiency and decrease of Insulin can cause-
• Type 1 diabetes- It is a type of autoimmune disease. These diseases harm the body itself. Your body can’t make insulin in this type because your immune system has destroyed all the insulin-producing cells in your pancreas.
• Type 2 diabetes- In this, the body has become resistant to the effects of insulin. This means your body needs more insulin to get similar effects. Therefore, it overproduces insulin to keep blood glucose levels normal. But after many years of overproduction, the insulin-producing cells in the pancreas burn out. This type affects people of any age but typically develops later in life.

Note: Insulin is considered an anabolic (construction of molecules) hormone. There are certain receptors on insulin and they perform intrinsic tyrosine kinase activity. The proteins present include the insulin receptor substrate proteins (IRS) proteins. The substrates present are also commonly referred to as docking proteins. Protein-protein interaction is important for the signaling mechanism.