Which gland secretes insulin and glucagon to regulate blood sugar levels?

• A. Pancreas
• B. Liver
• C. Adrenal gland
• D. Thyroid

Answer: (A)

Insulin and glucagon are hormones that regulate blood sugar, and they come from the pancreas, specifically the islets of Langerhans. When blood glucose rises, insulin is released to help cells take up glucose and to promote its storage as glycogen in the liver, lowering the blood sugar. When glucose falls, glucagon is released to signal the liver to release glucose back into the bloodstream, raising blood sugar. This coordinated action keeps glucose levels within a narrow range. Other glands don’t produce both of these hormones—adrenal glands make hormones for stress responses, the thyroid makes thyroid hormones, and the liver stores glycogen but does not secrete insulin or glucagon.