Final answer:
Amino acids are the building blocks of proteins. They consist of a central carbon atom bonded to an amino group, a carboxyl group, and a hydrogen atom. The R group differentiates one amino acid from another and determines its properties.
Step-by-step explanation:
Amino acids are the monomers that make up proteins. They have the same fundamental structure, consisting of a central carbon atom bonded to an amino group (-NH₂), a carboxyl group (-COOH), and a hydrogen atom. Additionally, each amino acid has another atom or group of atoms called the R group, which distinguishes one amino acid from another. The R group varies in structure and determines the chemical nature and properties of the amino acid.