What action does glucagon perform on glycogen?

Glucagon plays a crucial role in the regulation of blood sugar levels by stimulating the breakdown of glycogen into glucose. When blood glucose levels are low, glucagon is secreted from the alpha cells of the pancreas. It binds to specific receptors on liver cells, initiating a cascade of reactions that leads to the conversion of glycogen, a stored form of glucose, back into glucose. This glucose is then released into the bloodstream, increasing overall blood sugar levels to provide energy for the body, particularly between meals or during times of fasting.

This mechanism is essential for maintaining homeostasis, as it ensures that the body has a readily available energy source when direct intake from food is not possible. Thus, the effect of glucagon is vital for regulating metabolism and ensuring that organs and tissues receive the energy they require for optimal function.