Aprotein is a large polypeptide. polypeptides are polymers of amino acids joined together through a special type of bond: the peptide bond. understanding the chemistry and properties of the peptide bond is fundamental to understanding protein structure (and function). first, identify the n- and c-termini of the peptide. then, identify those bonds that comprise the peptide bond for each labeled bond. finally, determine the number of amino acids in the peptide depicted.