Carbohydrates: Top Energy Suppliers

By the time you are reading these lines and trying to understand their content, your nerve cells are doing a job, so they use the energy that has been released from the oxidation of molecules of a carbohydrate called glucose.

Carbohydrate Classification

A simplified classification of carbohydrates, or glycids, consists of dividing them into three main categories: monosaccharides, oligosaccharides and polysaccharides.

Monosaccharides: The Simplest

Monosaccharides are simple carbohydrates of molecular formula (CH2O)nowhere n is a minimum of 3 and a maximum of 8. These are the true sugars, water soluble and generally sweet in taste. The least carbon atoms are trioses (they contain three carbon atoms). The most biologically known are those formed by five carbon atoms (called pentoses) and those formed by six carbon atoms (hexoses).

In the table below you will find the most known hexoses and pentoses, their biological roles and sources of obtaining. Don't worry about molecular formulas, just fix the sources where sugars are found and their biological role.

Ribose Deoxyribose
Biological role Biological role

Raw material for the manufacture of nucleic acid RNA. Molecular Formula: C5H10O5

Raw material for the manufacture of nucleic acid DNA. Molecular Formula: C5H10O4

Glucose Fructose Galactose
Biological role Biological role Biological role

Leading energy provider for cellular work. It is the basis for the formation of most complex carbohydrates. Produced in photosynthesis by plants. Found in the blood, honey and tissues of vegetables.
Molecular Formula: C6H12O6

It also provides energy to the cell. Found mainly in sweet fruits and also in human sperm.
Molecular Formula: C6H12O6

Energetic role. Found in milk as a component of disaccharide lactose.
Molecular Formula: C6H12O6