HUMAN NUTRITION

Detailed explanation-1: -Glycogenolysis is the biochemical pathway in which glycogen breaks down into glucose-1-phosphate and glucose. The reaction takes place in the hepatocytes and the myocytes. The process is under the regulation of two key enzymes: phosphorylase kinase and glycogen phosphorylase.

Detailed explanation-2: -In liver, where glycogen is stored as a reserve of glucose for extrahepatic tissues, the glycogen-metabolizing enzymes have properties that enable the liver to act as a sensor of blood glucose and to store or mobilize glycogen according to the peripheral needs.

Detailed explanation-3: -Between meals, the liver breaks down glycogen and releases free glucose to the bloodstream. In contrast, glycogen serves as an energy reserve that can be rapidly mobilized to fuel contraction in muscle cells. Muscle does not release glucose to the circulation, its glycogen stores are exclusively used in that tissue.