Question

Pancreatic cells that secrete insulin are called:
a. Alpha cells
b. Beta cells
c. Chief cells
d. Delta cells

Answer 1

Hint: Endocrine glands are the glands that secrete substances directly into the bloodstream and the exocrine glands secrete substances into ducts. Pancreas is a dual gland that acts as both endocrine gland and exocrine gland. To answer this question the knowledge about the different cells of the pancreas and its secretions are necessary.

Complete answer:
Pancreas is an organ that is present behind the stomach. Pancreas being a dual gland it has dual function and secretes a number of enzymes into the bloodstream and into the pancreatic duct. There are a group of cells in the pancreas called the islets of Langerhans which perform the endocrine function. Different types of cells in the islets of Langerhans are:
• Alpha cells: produces glucagon.
• Beta cells: produces insulin and amylin.
• Delta cells: produces somatostatin.
• Epsilon cells: produces the hunger hormone – ghrelin.
• Pancreatic polypeptide cells (PP): produces pancreatic polypeptide.

The exocrine part of the pancreas secretes pancreatic proteases, pancreatic lipase, pancreatic amylase, ribonuclease, deoxyribonuclease, gelatinase and elastase. The epithelial cells in pancreatic ducts are responsible for bicarbonate and water secretion into the pancreatic juice.

Hence, the correct answer is option (B).

Additional information:
- Insulin allows the body to use glucose for energy and converts excess glucose in the blood to glycogen which is stored in the liver and muscles.
- Glucagon uses the stored glycogen from and muscles and converts it to glucose especially when the body is in starving condition.
- Amylin is produced along with insulin and acts as a satiety agent and also inhibits glucagon secretion. Somatostatin inhibits the secretion of both insulin and glucagon.
- Ghrelin is a hormone that stimulates appetite and increases food intake, hence called ‘the hunger hormone’.
- The function of pancreatic polypeptide (PP) is to self-regulate pancreatic secretion activities.

Note: In people with type I diabetes, the pancreas can’t make insulin and hence the glucose cannot be used by the cells and gets accumulated in the blood. In type II diabetes the pancreas is able to make insulin but the body is unable to use the insulin properly.
It is possible for a person to live without pancreas if the person takes insulin and enzyme supplements for digestion.