What action does Glucagon perform in the body?

Glucagon primarily functions to increase blood glucose levels by facilitating the conversion of glycogen stored in the liver into glucose. When blood sugar levels drop, glucagon is released from the alpha cells of the pancreas. This hormone prompts the liver to engage in glycogenolysis, a process that breaks down glycogen—essentially stored glucose—into free glucose molecules that can then be released into the bloodstream. This action is vital for maintaining energy availability, particularly during fasting or periods of intense physical activity.

The capability of glucagon to raise blood glucose levels is essential for ensuring that the body has adequate energy supplies, especially for the brain, which predominantly uses glucose as its primary energy source. Understanding this function is critical for managing conditions like hypoglycemia, where blood sugar levels can become dangerously low.