Describe the relationship between the digestive system and the circulatory system in maintaining the homeostasis of glucose levels in the body

The digestive system and circulatory system together maintains the blood glucose levels in the body. The pancreas releases hormones, insulin and glucagon which controls the blood glucose levels, into the blood stream. The liver helps in the glucose metabolism and the glucose homeostasis by glycogenesis and glycogenolysis. The circulatory system transports the glucose and pancreatic hormones in the blood to the body cells.

Explanation:

Homeostasis is the tendency of the various systems in the human body to stay in optimal ranges for health by self regulation through feedback controls. It is very important because it maintains equilibrium and provides stability to the human body.

Glucose homeostasis is the process of maintaining glucose level in the blood at a steady-state level.  The digestive and circulatory systems together maintains the blood glucose levels. The organs of the digestive system, the pancreas and liver help to keep the blood glucose at normal levels. When the blood glucose levels are low, the digestive system receptors and the brain respond by making some sensations which prompt us to eat thereby increasing the blood glucose levels.

The pancreas is a gland organ located in the abdomen. The exocrine part of the pancreas produces enzymes which helps in the digestion of food. The digestive system converts carbohydrates into glucose and is then absorbed into the blood stream. With the help of insulin hormone, the glucose is transported to the cells for energy production. The hormones insulin and glucagon are produced by the endocrine part (islets of Langerhans) of the pancreas.

When blood glucose levels rises, pancreatic beta cells release insulin. Insulin also converts glucose into glycogen (glycogenesis) for storage in the liver. When blood glucose levels decreases, pancreatic alpha cells release the hormone glucagon. In the liver, glucagon breaks down the stored glycogen into glucose (glycogenolysis). The glucose then enters the bloodstream and restores the blood glucose levels to normal. Thus liver also plays an important role in the homeostasis of blood glucose levels in the body. The circulatory system plays an important role in the transport of glucose and pancreatic hormones in the blood to the body cells.

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