The pancreas is an irregular-shaped gland that is located just below the stomach and adjacent to the duodenum of the small intestine. It averages between 4.7 and 5.8 inches (12 and 15 centimeters) in length, and a little over 0.8 inches (2 centimeters) in thickness. For descriptive purposes, it is divided into three major sections, although there is little difference in the physiology of the sections. The head is located closest to the duodenum and is connected to the digestive tract by two ducts. The hepatopancreatic duct is a common duct formed by the linking of the bile duct and pancreatic ducts. A second duct, called the duct of Santorini, directly connects the pancreas to the duodenum. Moving away from the duodenum and the head of the pancreas are the regions called the body and tail.
The pancreas actually represents two separate organs, both of which contribute to digestion, which are integrated into a single structure. A por tion of the pancreas is an exocrine gland, meaning that it secretes com pounds into a cavity.
The second major area of the pancreas is the endocrine tissue, which secretes chemicals into the bloodstream. In general, the exocrine functions of the pancreas can be described as those directly involved with the processing of nutrients in the duodenum, while the endo crine is best described as those functions that involve hormones and the regulation of glucose homeostasis in the body. Both types of tissue exist throughout the pancreas.