Carbohydrates are classified into three subtypes: monosaccharides, polysaccharides and:

1. The subtype depends on how many monomer units the molecule holds. 2. One unit is a monosaccharide and many units make a polysaccharide. 3. Two units joined together form a disaccharide. 4. Triglycerides and phospholipids are lipids, and oligopeptides are short protein chains. _Source: OpenStax Biology for AP(R) Courses (CC BY 4.0), Ch 3 'Biological Macromolecules', sections 3.1-3.5_