Answer;
Amino acids
Proteins are important biomolecules that build organisms and direct chemical reactions. Proteins are polymers composed of long chains of Amino acids.
Explanation;
Proteins are macromolecules that are composed of amino acids, and a single protein molecule may contain as many as 5,000 amino acid molecules. The amino acids that make up the protein molecule constitute its primary structure
Amino acids are the basic building blocks of proteins; contains a carboxyl group (-COOH) and an amino group (-NH2).