<prompt> Main source of energy derived fromFatGlycogenLactateKetone  <response>: Glycogen is the reserve carbohydrate in animals. It is stored in liver and muscles.The phosphorylated enzyme is less sensitive to allosteric inhibitors. Thus even if cellular ATP and glucose-6-phosphate are high, Phosphorylase will be active. The glucose-1-phosphate produced from glycogen in the liver may be conveed to free glucose for release to the blood. 