Glucose

a monosaccharide found in its dextrorotatory form (D-glucose)in the free state in fruits and other parts of plants, and combined in glucosides, glycogen, disaccharides, and polysaccharides (starch cellulose)

Description
Glucose is the chief source of energy in human metabolism, the final product of carbohydrate digestion (the product of complete hydrolysis of cellulose, starch and glycogen), and the principal sugar of the blood. Insulin is required for the use of glucose by cells; in diabetes mellitus the level of glucose in the blood is excessive and if exceeding 140 mg/dL also leads to raised urine sugar levels.