Explain how blood glucose levels are controlled and how this is an example of negative feedback mechanisms.

The pancreas detects rises in blood glucose levelsThis triggers pancreatic beta cells to secrete insulin, and inhibits alpha cells from secreting glucagonInsulin stimulates the uptake of glucose into cells and glycogenesis occursThis results in a decrease in blood glucose levelsIf the blood glucose levels fall by too much, the pancreas detects thisThis inhibits the secretion of insulin and triggers the release of glucagonGlucagon acts on liver cell receptorsIt triggers glycogenolysis and gluconeogenesisCells release the newly formed glucose into the blood and blood glucose levels rise

HL

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