Answer the question on the basis of passage given below:

Living systems are made up of various complex biomolecules like carbohydrates, proteins, nucleic acids, lipids etc. Proteins and carbohydrates are essential constituents of our food. Carbohydrates are primarily produced by plants and form a very large group of naturally occurring organic compounds. SOme common examples are cane sugar, glucose, starch etc.

Insulin, generally given to diabetic patient is a:

Protein

The correct answer is option 2. Protein.

Insulin is a hormone produced by the pancreas, specifically by the beta cells in the islets of Langerhans. Its primary role is to regulate blood glucose levels by facilitating the uptake of glucose into cells and promoting its storage as glycogen in the liver and muscle. Insulin is a protein composed of two polypeptide chains:

A Chain: 21 amino acids long.

B Chain: 30 amino acids long.

These two chains are connected by disulfide bonds. The amino acid sequence and the specific arrangement of these chains are crucial for insulin's biological activity.

Polypeptide Chains: Insulin is made up of amino acids, which are the building blocks of proteins. Proteins are defined by their amino acid composition and structure. Insulin’s two chains (A and B) and the presence of disulfide bonds confirm its classification as a protein.

Glucose Regulation: When blood glucose levels rise after eating, insulin is released into the bloodstream. Insulin helps cells throughout the body absorb glucose from the blood, reducing blood sugar levels. It promotes the conversion of glucose to glycogen in the liver and muscles for storage.

Metabolic Effects: Insulin influences various metabolic processes, including protein synthesis, fat storage, and glucose metabolism.

Comparison with Other Categories

Carbohydrates: These are organic compounds made up of carbon, hydrogen, and oxygen, typically in a 1:2:1 ratio. They include sugars, starches, and fibers. Carbohydrates are used primarily for energy. Insulin, however, is not a carbohydrate but a protein hormone.

Vitamins: These are organic compounds required in small amounts for essential biochemical processes. Vitamins are not involved in the regulation of blood glucose levels directly. Insulin is not classified as a vitamin.

Nucleic Acids: These include DNA and RNA, which are responsible for storing and transmitting genetic information. Nucleic acids are not involved in the direct regulation of blood glucose. Insulin does not fall into this category.

Why Insulin is a Protein

The defining characteristics of proteins include:

Amino Acid Composition: Proteins are polymers made up of amino acids. Insulin’s structure fits this definition, as it consists of a specific sequence of amino acids.

Functionality: Proteins have diverse functions, including enzymatic activity, signaling, and structural roles. Insulin’s role in glucose regulation and its hormone function align with protein characteristics.

Conclusion

Insulin is classified as a protein because it is composed of amino acids and has a specific sequence and structure typical of proteins. It is crucial for regulating blood glucose levels and is distinct from carbohydrates, vitamins, and nucleic acids in its function and chemical makeup. Therefore, option 2 (Protein) is the correct classification for insulin.