<prompt> Peptide bond is formed between:-Carboxyl group on one amino acid and the R-group of adjacent amino acidCarboxyl group on both amino acidsAmino group on one amino acid and the carboxyl group of the adjacent amino acidThe amino group of both amino acids  <response>: Proteins are polypeptides Series of amino acids linked peptide bonds A peptide bond is a special type of amide bond between the a-carboxyl group of one amino acid and the a-amino group of the adjacent amino acid. 