In the context of glucose regulation, what is one of the roles of the liver?

The liver plays a crucial role in glucose regulation, particularly through its ability to release glucose into the bloodstream in response to hormonal signals. When blood glucose levels drop, the pancreas secretes glucagon, a hormone that signals the liver to convert stored glycogen into glucose and release it back into the bloodstream. This process is essential for maintaining stable blood glucose levels, especially during fasting or between meals.

The liver's glycogenolysis, which is the breakdown of glycogen into glucose, ensures a continuous supply of glucose for the body's energy needs. This action counteracts periods of low blood sugar, helping to maintain homeostasis.

In contrast, the liver does not absorb glucose from the bloodstream; absorption primarily occurs in the intestines. While the liver does store glucose, it does so as glycogen, not as protein. Additionally, the liver regulates blood glucose levels indirectly; while it can produce and release glucose, it does not directly decrease blood glucose levels. Instead, glucose uptake by muscle and adipose tissue, influenced by insulin, lowers blood glucose levels. Hence, the vital role of the liver in glucose regulation is best represented by its capacity to release glucose in response to glucagon.