ABSTRACT
A monosaccharide has the general formula (CH2O)n and contains either an aldehyde group or a ketone group. The free aldehyde or ketone group can reduce cupric ions (Cu2+) to cuprous ions (Cu+) and hence such a monosaccharide is called a reducing sugar. A monosaccharide or simple sugar, consists of a carbon chain with a number of hydroxyl (OH) groups and either one aldehyde group or one ketone group. Sugars that contain a free aldehyde or ketone group in the open-chain configuration can reduce cupric ions (Cu2+) to cuprous ions (Cu+) and hence are called reducing sugars. A sugar that bears an aldehyde group is called an aldose whereas a sugar with a ketone group is a ketose. The hydroxyl groups of simple monosaccharides can be replaced with other groups to form a range of sugar derivatives. For example, phosphorylated sugars such as glucose 6-phosphate are important metabolites in glycolysis.
