A polypeptide is defined as what?

A polypeptide is defined as what?

• A. A chain of amino acids
• B. A lipid molecule
• C. A carbohydrate chain
• D. A nucleotide sequence

Answer: (A)

Polypeptide is a chain of amino acids linked by peptide bonds. This polymer forms the building blocks of proteins, and the specific sequence of amino acids dictates how it folds into a functional shape. Some polypeptides alone can act as a complete protein, while others pair up or combine with additional polypeptides to make a larger protein complex. The other options describe different biomolecule classes—lipids are not built from amino acids, carbohydrates are sugar chains, and nucleotides form nucleic acids—so they don’t define a polypeptide.

Polypeptide is a chain of amino acids linked by peptide bonds. This polymer forms the building blocks of proteins, and the specific sequence of amino acids dictates how it folds into a functional shape. Some polypeptides alone can act as a complete protein, while others pair up or combine with additional polypeptides to make a larger protein complex. The other options describe different biomolecule classes—lipids are not built from amino acids, carbohydrates are sugar chains, and nucleotides form nucleic acids—so they don’t define a polypeptide.