Respuesta :

A polypeptide is a peptide composed of two amino-acid and a peptide bond is a chemical bond formed between two molecules, when the carboxyl group of one molecule reacts with the amino group of the other molecule, releasing a molecule of water.
D= it is two organic compounds that contains two amino acids that is joined by one single peptide bond ot one amino acid with two peptide bonds 

P= chemical bond formed from between two molecules when one molecule of carboxyl group reacts with one molecule from an amino group releasing h20