A protein hormone synthesized in the pancreas that regulates blood sugar levels by facilitating the uptake of glucose into tissues is

• A. Glucagon
• B. Amylin
• C. Insulin
• D. Somatostatin

Answer: (C)

Insulin is the protein hormone produced by pancreatic beta cells that lowers blood glucose by helping tissues take up glucose. It triggers a signaling cascade that moves GLUT4 glucose transporters to the cell membrane, especially in muscle and adipose tissue, increasing glucose entry into those cells. In the liver, insulin promotes glycogen synthesis and suppresses glucose production, further lowering blood sugar after meals. Other pancreatic hormones have different roles: glucagon raises blood glucose by promoting glycogen breakdown and gluconeogenesis; amylin is co-secreted with insulin and helps regulate postprandial glucose by slowing gastric emptying and dampening glucagon release; somatostatin inhibits the release of several hormones, including insulin and glucagon, modulating their effects.