Describe the Process of Glycogen Breakdown in Muscle

Question

Examlex · Accepted Answer

The Answer is Glycogen is a highly branched polysaccharide that serves as a storage form of glucose in the body, particularly in the liver and muscle cells. The structure of glycogen consists of a core protein called glycogenin, with glucose molecules attached in chains through alpha-1,4-glycosidic bonds and branching points created by alpha-1,6-glycosidic bonds.

The breakdown of glycogen in muscle cells, known as glycogenolysis, is a crucial process for providing energy during periods of high demand, such as exercise. This breakdown reaction is catalyzed by the enzyme glycogen phosphorylase, which cleaves glucose molecules from the non-reducing ends of the glycogen chains, releasing glucose-1-phosphate as the breakdown product. This process continues until the branching points are reached, at which point the enzyme debranching enzyme is required to remove the branching glucose molecule and allow further glycogen phosphorylase action.

The glucose-1-phosphate produced from glycogen breakdown can then be converted to glucose-6-phosphate and enter glycolysis to generate ATP for muscle contraction. This process allows for rapid mobilization of glucose stores in the form of glycogen to meet the energy demands of muscle cells.

Describe the Process of Glycogen Breakdown in Muscle

Definitions: