Final answer:
Glucagon is produced by the alpha cells of the pancreas and prompts the liver to convert stored glycogen back into glucose when blood sugar levels are low, thereby regulating glucose levels in the blood.
Step-by-step explanation:
When the blood sugar level falls too low, the hormone glucagon is released, causing the liver to release stored glycogen into the blood. Glucagon stimulates the breakdown of glycogen (glycogenolysis) in the liver, which results in the release of glucose into the bloodstream. This helps to raise the blood sugar levels back to normal.
Glucagon is a hormone produced by the alpha cells of the pancreatic islets of Langerhans when blood glucose levels drop. Its primary function is to maintain normal levels of glucose in the blood, particularly during periods of fasting or increased energy expenditure. Glucagon promotes the process of glycogenolysis, which involves converting glycogen back into glucose. The liver plays a central role in this process, as it stores significant amounts of glycogen and has the capacity to release glucose into the circulation, thus raising blood glucose levels to a normal range. This regulatory mechanism is a crucial aspect of homeostasis, the body's effort to maintain a stable internal environment despite external changes.