Insulin is secreted by which type of pancreatic cells?

Insulin is secreted by beta cells, which are located in the islets of Langerhans in the pancreas. These beta cells play a critical role in the regulation of glucose metabolism by producing insulin in response to rising blood sugar levels, such as after meals. Insulin facilitates the uptake of glucose by tissues, particularly muscle and adipose tissue, and promotes the storage of glucose as glycogen in the liver. This physiological process is important for maintaining normal blood glucose levels.

In the context of pancreatic cell types, alpha cells are responsible for secreting glucagon, which increases blood glucose levels by promoting the release of glucose stored in the liver. Delta cells secrete somatostatin, which regulates the endocrine system and inhibits the secretion of both insulin and glucagon. Acinar cells produce digestive enzymes to aid in digestion but do not play a role in hormone secretion related to blood glucose levels. Thus, the role of beta cells is specifically aligned with the production of insulin, making them the correct answer.