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noun, plural: trioses

A three-carbon monosaccharide


Monosaccharides are the simplest form of carbohydrates. They are classified according to the number of carbon atoms in a monosaccharide. In particular, a triose is a monosaccharide with three carbon atoms.

Two naturally occurring trioses are aldotriose (glyceraldehyde) and ketotriose (dihydroxyacetone). These trioses are important metabolites in cellular respiration. For instance, glyceraldehyde-3-phosphate (C3H7O6P) is a metabolites triose that serves as an intermediate in different metabolic pathways. It is produced together with dihydroxyacetone phosphate from the breaking down of β-D-fructose-1,6-bisphosphate during glycolysis by the action of fructose-bisphosphate aldolase.

Monosaccharides may also be classified based on the type of carbonyl group they contain. An aldose is a monosaccharide that contains an aldehyde group (-CHO) whereas a ketose is one that contains a ketone (C=O). Thus, an aldotriose is a triose with an aldehyde group. The carbonyl group is located at the end of the chain. A ketotriose, in contrast, is a triose with a keto group. The only ketotriose is dihydroxyacetone.

Word origin: tri- ("three") + -ose (relating to sugars)

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