Glucose is a simple carbohydrate, or sugar. It is one of several kinds of sugars. It is important because cells in an organism use it as a source of energy. Turning glucose into energy is called cellular respiration, which is done inside the cells of a living organism.Excess glucose are converted to fats and are stored in adipose tissues.

Glucose is made by plants in a process called photosynthesis. It can also be made by animals in their liver or kidneys.

Having the right amount of glucose available in a person's body is important.Glucose is essential in the proper functioning of the brain. It can be measured with a simple blood test. People that do not have enough glucose have low blood sugar levels. This is a health condition called hypoglycemia. People with too much glucose have hyperglycemia. They might have a health condition called diabetes.

Its chemical formula is C6H12O6. This means it has 6 carbon atoms, 12 hydrogen atoms, and 6 oxygen atoms bonded together.

How sugars work, and how glucose can be formed, was studied by a German chemist named Emil Fischer in the 1890s. His work earned him the 1902 Nobel Prize in Chemistry.[1]


There are two forms of glucose, the α- and β- forms. The only difference between them is the position of the hydroxyl group, above and below the plane of the ring of the molecule.

For α-glucose, the hydroxyl (-OH) group is located below the ring, while for β-glucose, the (-OH) group is located above.[2]


  1. "The Nobel Prize in Chemistry 1902 - Emil Fischer". Nobel Prize Committee.
  2. [ "A Guide to α and β Carbohydrates"] Check |url= value (help) (PDF). University of California, Los Angeles. Retrieved 10 June 2014.