Monosaccharides are a group of simple carbohydrates that are essentially a simple form of sugars. They can not be broken down into smaller carbohydrates.

They are part of a group of other carbohydrates including:

– Oligosaccharides

Monosaccharides are building blocks of large carbohydrates. There are several different types some found in nature and others are synthesized

Chemically they have aldehyde or ketone groups and typically a hydroxyl group (-OH) and a carbonyl group (C=O) added on.

When the sugar has an Aldehyde it is called Aldose
When the sugar has a Ketone it is called Ketose

Can be divided depending on a number of carbons:

1.)  Triose –  3 carbon atoms
2.)  Tetrose  –  4 carbon atoms
3.)  Pentose  –  5 carbon atoms
4.)  Hexose  – 6 carbon atoms
5.)  Heptose – 7 carbon atoms
6.)  Octose – 8 carbon atoms
7.)  Nonose  – 9 carbon atoms
8.)  Decose  – 10 carbon atoms

Types of Monosaccharides


1.)  Aldotriose: D-Glyceraldehyde
2.)  Aldotetroses:  D-Erythrose, D-Threose
3.)  Aldopentoses: D-Ribose, D-Arabinose, D-Xylose, D-Lyxose
4.)  Aldohexoses:  D-Allose, D-Altrose, D-Glucose, D-Mannose, D-Gulose, D-Idose, D-Galactose, and T-Talose


1.)  Ketotriose:  Dihydroxyacetone
2.)  Ketotetrose:  D-Erythrulose
3.)  Ketopentoses:  D-Ribulose, D-Xylulose
4.)  Ketohexoses:  D-Psicose, D-Fructose, D-Sorbose, D-Tegatose

Some of the more common monosaccharides include:

–  Glucose
–  Fructose
–  Galactose
–  Ribose

Some common found uses of monosaccharides include:

 Vitamin C
–  Sorbitol
–  Other sweetening agents
–  Amino sugars
–  others