For example, a protein is a polymer whose subunits are selected from a set of twenty or more amino acids, carbohydrates are formed from sugars known as monosaccharides, oligosaccharides, and polysaccharides, lipids are formed from fatty acids and glycerols, and nucleic acids are formed from nucleotides.
For instance, a protein is made up of subunits selected from among twenty or more amino acids; carbohydrates are constructed from sugars such as monosaccharides, oligosaccharides, and polysaccharides; lipids are derived from fatty acids and glycerols; and nucleic acids are assembled from nucleotides.