Carbohydrates can be represented by the stoichiometric formula (CH2O)n, where n is the number of carbons in the molecule. Therefore, the ratio of carbon to hydrogen to oxygen is 1:2:1 in carbohydrate molecules. Carbohydrates are the main source of energy for the body.
Carbohydrates are essential macromolecules that are classified into three subtypes: monosaccharides, disaccharides, and polysaccharides.
- Monosaccharides are simple sugars made up of three to seven carbons, and they can exist as a linear chain or as ring-shaped molecules. Glucose, galactose, and fructose are monosaccharide isomers.
- Disaccharides (di- = “two”) form when two monosaccharides undergo a dehydration reaction
- A long chain of monosaccharides linked by glycosidic bonds is known as a polysaccharide (poly- = “many”).