Glycogenesis is the process by which glucose molecules are converted into glycogen for storage in the liver and muscles. It occurs when blood glucose levels are high, such as after a meal, and the body needs to store excess glucose for later use. Glycogenesis is primarily regulated by the hormone insulin, which stimulates the conversion of glucose into glycogen. This process involves a series of enzymatic reactions, including the activation of glucose to glucose-6-phosphate, its conversion to glucose-1-phosphate, and the addition of multiple glucose molecules to form glycogen. Glycogen can be broken down back into glucose through a process called glycogenolysis when the body requires energy.