Question

Glycogen is a polymer of/ Repeating unit of glycogen is
A. Galactose
B. Glucose
C. Fructose
D. Sucrose

Answer 1

Glycogen is a multi-branched polymer which is mainly stored in liver and muscles. It provides the body with a readily available source of energy if the blood glucose level decreases.

Complete answer:
- Glycogen is a multibranched polysaccharide of glucose. It is accumulated in response to insulin and it is broken down into glucose in response to glucagon and it is mainly stored in the liver and the muscles.
- It provides the body with an instant source of energy when the blood glucose level decreases. It maintains blood glucose level and it is really important because glucose is the only fuel used by the brain virtually.
- The glucose is stored in the liver in the form of glycogen and in the muscles, it gets changed to glucose by the process of glycogenolysis. By the process of glycolysis, the energy in the form of ATP is provided to the muscles.

Let us check the above options:

Option A is Galactose. It is an incorrect option since glycogen is a multi-branched polymer of glucose not galactose. Therefore, it gets eliminated.
Option B which is Glucose, this option is correct since the repeating unit of glycogen is glucose. Therefore, it is the correct one.
Option C which is Fructose, glycogen is a polysaccharide of glucose not fructose and this makes it the incorrect option and it gets eliminated.
Option D which is Sucrose, is also the incorrect option since glycogen is not a polymer of sucrose but it is a polymer of glucose and therefore this option gets eliminated.

Hence, the correct answer is option (B).

Note: Glycogen is a substance which is deposited in body tissues in the form of carbohydrates and it is broken down in the form of glucose which provides an instant source of energy to muscles by the process of glycolysis. It maintains the blood glucose level too.