Final answer:
Glycogen is the storage form of glucose found in the liver and skeletal muscle cells of animals and serves as the main energy reserve that is quickly mobilized to maintain blood glucose levels.
Step-by-step explanation:
The storage form of glucose in animals, including humans, is called glycogen. Glycogen is a highly branched polymer of glucose monomers, which is similar in function to starch in plants. It's primarily stored in the liver and skeletal muscle cells. The liver glycogen serves as a key energy reserve for the body's overall glucose needs, while muscle glycogen is available for local muscle energy demands.
During periods of fasting or increased energy demand, glycogen is broken down in a process called glycogenolysis to release glucose into the bloodstream, maintaining an adequate level of blood glucose necessary for various bodily functions. Glycogen storage plays a crucial role in glucose homeostasis, helping to regulate blood sugar levels and serving as a quick energy source when needed.