What organ manufactures and stores most of the body's glycogen as a ready source of glucose?

Liver is the organ that manufactures and stores most of the body's glycogen as a ready source of glucose. The process of formation of glycogen is called glycogenesis, which is the primary carbohydrate stored in the liver and muscle cells of animals. It is formed from glucose under stimulation by insulin hormone, and takes place when the blood glucose levels are sufficiently high to allow excess glucose to be stored in liver and muscle cells.