please tell about `islets of langerhans` in detail .

The endocrine part of pancreas is made up of a special group of cells known as Islets of Langerhans.

Three kinds of cells found in the islets of Langerhans:

1. Alpha Cells:

• Secrete glucagon
• Glucagon stimulates the breakdown of glycogen into glucose in the liver.
• Therefore, glucagon is responsible for the rise in the sugar level of the blood.

2. Beta Cells:

• Secrete insulin
• Insulin maintains the rise of the blood sugar level.
• Insulin promotes glucose utilisation by the body cells.
• Insulin stimulates deposition of extra glucose as glycogen in muscles and liver.

3. Delta Cells:

• Secrete somatostatin
• Somatostatin controls the secretion of glucagon and insulin.