Question

Provide a brief overview of the mechanisms employed to accomplish the relatively constant blood glucose level in humans of ~5mM and comment on why it is necessary.

Answer 1

Glucose is the major energy source of the cell. It provides energy to almost all biological processes. Hence it is important to maintain constant glucose level in blood. The blood glucose level is maintained by a negative feedback mechanism. Pancreatic hormones insulin and glucagon are important in maintaining constant glucose level in blood. When the blood glucose level is increased it will gives negative signal to hypothalamus. It releases growth hormone inhibiting hormones which decreases the level of hGH (human growth hormone) and glycogen is not break down into glucose until the normal glucose level is achieved. When glucose level is too low, growth hormone releasing hormone is released from the hypothalamus and it will increase the level of hGH, the glucose level is increased by positive feedback loop. Alpha cells of pancreas secretes glucagon which breaks down glycogen into glucose. Insulin like receptors recognises glucose for uptakes into cell. This whole mechanism is regulates glucose level in blood.

   If the blood glucose level is not maintained constantly several disease conditions are arise. High blood glucose level leads to diabetes mellitus, liver disease and hyperthyroidism. Low level of blood glucose leads to hypothyroidism, Addison’s disease and other complications. Generally high blood is a common type of disease observed in glucose regulation. So it is necessary to maintain constant glucose level in blood.