Any of a class of monosaccharides having an aldehyde or hemiacetal functional group.
(carbohydrate) A saccharide containing a ketone functional group.
a monosaccharide sugar that contains the aldehyde group or is hemiacetal
any monosaccharide sugar that contains a ketone group or its hemiacetal
An aldose is a monosaccharide (a simple sugar) with a carbon backbone chain with a carbonyl group on the endmost carbon atom, making it an aldehyde, and hydroxyl groups connected to all the other carbon atoms. Aldoses can be distinguished from ketoses, which have the carbonyl group away from the end of the molecule, and are therefore ketones.
A ketose is a monosaccharide containing one ketone group per molecule. The simplest ketose is dihydroxyacetone, which has only three carbon atoms, and it is the only one with no optical activity.