<span>A polypeptide is a single linear chain of many amino acids, held together by amide bonds. A protein consists of one or more polypeptides (more than about 50 amino acids long). An oligopeptide consists of only a few amino acids (between two and twenty). </span>
A peptide bond<span> is a chemical bond that joins amino acids together where the carboxyl group of one amino acid bonds with the amino group of another. This forms a dipeptide, which is simply a compound consisting of two amino acids. It requires the loss of water to form a bond, which is a process called a dehydration synthesis reaction.</span><span> </span>
