Question

Glucose is stored as glycogen in
A) Pancreas
B) Bone
C) Kidney
D) Liver

Answer 1

Glucose is a simple carbohydrate molecule that is formed by the oxidation of the food. Glucose is the immediate source of energy. The surplus glucose is converted into glycogen and is stored in or body as the reserve of glucose in the tissues.

Complete answer:
Glycogen is the polymer of glucose that is present in mammalian and non-mammalian cells. It is a quick source of glucose as it can be immediately converted into glucose. The process of storing glucose into glycogen is as follows-

The carbohydrate and protein-containing meals are digested and they increase the sugar level in the blood. In response to the same, the pancreas secretes insulin. This activates the hepatocytes of the liver to secrete glycogen synthase. It polymerises the glucose to glycogen. So, the liver takes more glucose from the blood in order to convert it into glycogen and store it in the liver.

When the level of glucose drops, the insulin secretion is reduced and the glycogen synthesis stops. To fulfil this demand of glucose, the glycogen stored in the liver is broken down to glucose by the enzyme glycogen phosphorylase.

Pancreas- It is an endocrine organ that produces hormones. It produces insulin which reduces the glucose level in the blood and glucagon which increases the glucose level in the blood. Insulin triggers the conversion of glucose to glycogen.

Bone- Bone forms the structural framework of our body. It is made up of calcium and phosphorous.
Kidney- The kidney is the unit of excretion. They form urine which is the waste comprising of nitrogen, urea and other excess salts. The kidney filters extra glucose from our blood.

Therefore the correct answer is option D.

Note: The process of synthesis of glycogen from glucose is known as glycogenesis. It is important because it ensures that our body’s glucose which is the source of energy is not exhausted. Too much glycogen can be toxic to the liver.