Hormones regulate both the storage and the utilization of glucose as required. Glucose not immediately taken up by cells for fuel can be stored by the liver and muscles as glycogen or converted to triglycerides and stored in the adipose tissue. The body derives glucose from the breakdown of the carbohydrate-containing foods and drinks we consume. Glucose is the preferred fuel for all body cells. Figure 9.7 Pancreas Regulation of Blood Glucose Levels by Insulin and Glucagon On the other hand, elevated blood glucose levels stimulate the release of insulin. Glucagon plays an important role in blood glucose regulation because low blood glucose levels stimulate its release. Pancreatic islets, clusters of cells formerly known as the islets of Langerhans, secrete glucagon and insulin. Although it is primarily an exocrine gland, secreting a variety of digestive enzymes, the pancreas also has an endocrine function. The pancreas is a long, slender organ located near the stomach (see Figure 9.7).
