* Monosaccharides: These are the simplest sugars, the building blocks of more complex carbohydrates. Examples include glucose, fructose, and galactose.

* Disaccharides: These are formed by the joining of two monosaccharides. Examples include sucrose (table sugar), lactose (milk sugar), and maltose (malt sugar).

* Polysaccharides: These are complex carbohydrates made up of long chains of monosaccharides. Examples include starch, glycogen, and cellulose.

It's important to note that these are not the only biomolecules involved in carbohydrate metabolism. Other molecules like enzymes, vitamins, and minerals play crucial roles in breaking down and using carbohydrates for energy.