Polypeptides are polymers of amino acids.

• A. Monomers
• B. Oligopeptides
• C. Polymers
• D. Isomers

Answer: (C)

The key idea is understanding how polymers are built. A polymer is a large molecule made by linking together many repeating subunits, called monomers. Amino acids are the monomers that come together to form polypeptides, connected by peptide bonds into a chain. Because a polypeptide is composed of many amino acids joined in sequence, it fits the definition of a polymer. A shorter chain of amino acids is an oligopeptide, not typically described as a polymer, and isomers refer to molecules with the same formula arranged differently, which isn’t about polymer size or composition. So a polypeptide is a polymer of amino acids.