BIOMOLECULES AND ENZYMES

Detailed explanation-1: -Xylulose is a ketopentose, a monosaccharide containing five carbon atoms, and including a ketone functional group. It has the chemical formula C 5H 10O 5. In nature, it occurs in both the L-and D-enantiomers.

Detailed explanation-2: -Monosaccharides can be classified by the number x of carbon atoms they contain: triose (3), tetrose (4), pentose (5), hexose (6), heptose (7), and so on. Glucose, used as an energy source and for the synthesis of starch, glycogen and cellulose, is a hexose.

Detailed explanation-3: -Monosaccharides are also classified as aldoses or ketoses. Those monosaccharides that contain an aldehyde functional group are called aldoses; those containing a ketone functional group on the second carbon atom are ketoses.

Detailed explanation-4: -Glucose is the most abundant monosaccharide. Galactose, mannose, fructose and ribose are also of major biological importance.