Glucose is a carbohydrate and a simple sugar that is of great importance as a source of energy in human metabolism. To store larger amounts of energy, the body makes use of long chains of glucose called polysaccharides. Glycogen is a very important multi-branched polysaccharide which has much use for energy storage in human and other animal bodies. With a large number of basic sugars, it forms an efficient energy storage element in cells and in the liver. Glycogen stores in skeletal muscle serve as a form of energy storage for the muscle. | Image credit: Mikael Haggstrom, 2014, used by permission. |