Q.Within the islets of Langerhans of the pancreas, insulin is secreted by the

The pancreas is a heterocrine gland, combining a much larger exocrine portion (acinar cells, secreting digestive enzymes via a duct) with an endocrine portion, the islets of Langerhans, scattered through the exocrine tissue and secreting hormones directly into the blood. The islets contain alpha cells (secreting glucagon, which raises blood glucose via glycogenolysis/gluconeogenesis), beta cells (the most numerous islet cell type, secreting insulin, which lowers blood glucose by promoting cellular uptake and glycogenesis), delta cells (secreting somatostatin, which inhibits both insulin and glucagon release) and PP cells (secreting pancreatic polypeptide). Beca …