Glucoregulation
- Regulation of blood glucose is an example of homeostasis
- The concentration of glucose in the blood must be kept within a narrow range
- Excessively high levels of glucose in the blood can lead to cells of the body losing water by osmosis, which can be dangerous
- Excessively low levels of glucose in the blood can lead to the brain receiving insufficient glucose for respiration, potentially leading to a coma or even death
- Blood glucose levels are regulated by the pancreas and the liver using hormones insulin and glucagon
- Insulin stimulates cells to take in glucose from the bloodstream (particularly liver and muscle cells)
- In liver and muscle cells excess glucose is converted into glycogen (a polymer of glucose) for storage
Examiner Tip
You should be able to extract information and interpret data from graphs that show the effect of insulin on blood glucose levels in people with and without diabetes.
Knowledge of the hormone glucagon is only required for higher tier candidates.