Glucagon is the readily available energy stored in the liver and muscles and is quickly metabolized. True or false?
The correct answer and explanation is:
The statement is false.
Glucagon is not the energy stored in the liver and muscles. Instead, glucagon is a hormone produced by the pancreas that plays a key role in regulating blood sugar levels. When blood glucose levels are low, glucagon is released into the bloodstream to signal the liver to release stored glucose (glycogen) into the blood to increase blood sugar levels. This process is known as glycogenolysis.
In contrast, the form of energy that is stored in the liver and muscles is glycogen, not glucagon. Glycogen is a polysaccharide composed of glucose molecules that is stored in the liver and muscle tissue. When the body needs energy and blood sugar levels are low, glycogen is broken down into glucose through the action of enzymes like glycogen phosphorylase. This glucose can then be used by cells for energy.
The liver stores a significant amount of glycogen, which can be released into the bloodstream to maintain blood glucose levels, especially during fasting or between meals. Muscles also store glycogen, but it is primarily used by the muscles themselves during physical activity.
Thus, while glucagon helps to regulate the release of glucose from glycogen stores, it is not the stored energy itself. Instead, glycogen serves as the body’s readily available form of stored energy, particularly in the liver and muscles.