Pancreas. Artwork of the pancreas (orange) and the surrounding abdominal organs. The pancreas is 15- 20 centimetres in length with an elongated shape. It lies behind the stomach, which is seen covering it in this view. Cells in the pancreas secrete digestive juices and the hormones insulin and glucagon, which regulate blood sugar levels. The digestive juices collect in a central duct running from upper right down to the head of the pancreas at lower left. Here, it joins with the common bile duct that brings bile from the gall bladder (far left). These digestive juices are discharged into the duodenum, the beginning of the small intestine that receives food from the stomach.