# Glucose --- **Glucose** is without a doubt the most important of all [[monosaccharide|monosaccharides]]. It is *the* most common source of chemical [[energy]] used by organisms, and its [[metabolism map.png|metabolism]] is a core genetic pathway in bacteria, archaea and eukaryotes. It is somewhat counterintuitive, but despite its fantastic importance to biology, it is not an essential [[nutrients]], because we can generate it though [[gluconeogenesis]]. Glucose's chemical formula is $C_6H_{12}O_6$, the same as other monosaccharides. The difference between them is simply the *arrangement* of molecules. The yellow highlighted area below is what distinguishes glucose from other monosaccharides. ![[glucose.png]] *The oxidation of glucose is at the center of metabolism*. Glucose is [[metabolism|metabolized]] into ATP through one of two general pathways, [[cellular respiration]] and [[fermentation]] where it is [[redox#^oxidation|oxidized]] through a long series of carefully controlled redox reactions. ## Why is Glucose so Important? Glucose is such an important molecule for two reasons. First off, it stores an incredible amount of energy in its [[covalent bond|covalent bonds]]. All the C–C and C–H bonds are very high energy bonds, and breaking those down can release a lot of energy. Secondly, it contains carbon in the first place, which cells can use to build up their own organic molecules. The question then is, why glucose in particular instead of some other carbohydrate ring? It's hard to say exactly, but scientists' best guess is that either it's the best candidate for making [[glycogen]], or it was just the first one we started using and we hitched all our horses to the glucose wagon. ___