Which cells secrete insulin in the pancreas?

• A. Alpha
• B. Beta
• C. Delta
• D. PP

Answer: (B)

Insulin is produced by beta cells in the islets of Langerhans of the endocrine pancreas. When blood glucose rises after a meal, these beta cells release insulin, which enables glucose to enter muscle and fat cells and also reduces glucose production by the liver, thereby lowering blood glucose levels. Other pancreatic islet cells have different roles: alpha cells secrete glucagon to raise blood glucose during fasting, delta cells release somatostatin to modulate hormone release, and PP cells secrete pancreatic polypeptide, which influences gastrointestinal function. The beta cells are the ones responsible for insulin secretion, making them the correct answer.