Which statement best describes glycogen's role in animals?

Glycogen serves as an energy storage molecule in animals, which is crucial for maintaining energy supplies in various physiological activities. It is a polysaccharide composed of glucose units and is predominantly stored in the liver and muscle tissues. When the body requires energy, glycogen can be rapidly broken down into glucose, which can then be used in cellular respiration to generate ATP, the energy currency of the cell.

This function of glycogen is essential for sustaining energy during periods of fasting, intense physical exercise, or any situation where immediate energy is required. As the body's energy needs fluctuate, glycogen provides a readily accessible source of glucose, making it a vital component of metabolic processes. The body's ability to store energy in the form of glycogen also allows it to maintain stable blood glucose levels, thus supporting overall metabolic homeostasis.