Pancreas – Tutorial
Please read Unit 10 – Introduction to Digestive System Tissues prior to completing the activities in this chapter.
Introduction to the Pancreas
The pancreas is a complex glandular structure located within the mesenteries (visceral peritoneum) posterior to the inferior border of the stomach and the duodenum of the small intestine. The pancreas differs from many other endocrine organs in that it carries out both endocrine and exocrine functions. The endocrine portion of the pancreas is comprised of small clusters of cells known as pancreatic islets (islets of Langerhans) which make up approximately 1% of the pancreas by volume. The pancreatic islets consist of four different types of cells. Alpha islet cells secrete glucagon, beta islet cells secrete insulin, delta islet cells secrete somatostatin, and pancreatic polypeptide cells (gamma cells) produce the hormone pancreatic polypeptide.
The exocrine portion of the pancreas is comprised of clusters of secretory cells known as pancreatic acini and their associated ducts which make up approximately 99% of total pancreatic volume. The exocrine products secreted by the pancreatic acini consist of a variety of digestive enzymes that are transported via a network of pancreatic ducts into the lumen of the duodenum.
