Insulin production. Artwork of the human pancreas showing production of the hormone insulin. The pancreas (yellow) is a tapered gland situated in the loop of the duodenum (grey tube) and below the liver (top left) and gall bladder (pear-shaped). The pancreas has both digestive and hormonal functions. Its exocrine tissue produces digestive enzymes which pass into the intestine through the pancreatic duct (yellow tube). Production of the hormone insulin by the endocrine pancreas is shown inset. A beta cell (red) contained within an islet of Langerhans secretes insulin (blue) into a capillary (grey). Insulin regulates the levels of sugar (glucose) in the bloodstream.