Hint: When blood glucose levels are high, then the excess glucose is stored in the liver or muscle in the form of glycogen and the process of formation of glycogen from glucose is called glycogenesis. The process of glycogenesis is under the influence of hormone insulin.
Complete answer: Glucose molecules are converted to glycogen by the process of glycogenesis in the liver during rest periods or by stimulation of insulin hormone under high glucose levels. Process of glycogenesis is as follows : 1. Conversion of glucose to glucose 6 phosphate by the action of glucokinase (ATP is converted to ADP). 2. Glucose 6 phosphate is converted to intermediate glucose 1-6 bisphosphate and then to glucose 1 phosphate by the action of phosphoglucomutase. 3. Then UDP glucose is produced from glucose 1 phosphate by the action of enzyme UDP glucose pyrophosphorylase. 4. Seven UDP glucose molecules are added to tyrosine molecules by the action of glycogen enzyme and alpha 1-4 bonds are produced. 5. Glycogen synthase binds to the glycogen chain and UDP glucose is added to 4 hydroxyl groups of glycosyl residue present on the non-reducing chain. Furthur glycogen branching enzymes produce branches in the glycogen by the production of alpha 1-6 glycosidic bonds.
Note: Glycogenesis is the process of storing excess glucose in the form of glycogen in the liver. Storing glucose in the form of glycogen makes sure that the body always gets enough glucose. When this glucose is needed as an energy source by the body, glycogen stored in the liver is converted to glucose by the process of glycogenolysis.