Question #388f8

1 Answer
Jan 3, 2016

Both polypeptides and proteins contain peptide bonds,


A peptide bond is the #"–CO-NH-"# bond formed when the #"COOH"# group of one amino acid reacts with the #"NH"_2# group of a second amino acid.

A biopolymer is a polymer produced by a living organism.

Polypeptides and proteins are two classes of biopolymers containing peptide bonds.

Polypeptides are polymers of amino acids typically containing less than 40 amino acid units.

Glucagon is a polypeptide chain of 29 amino acids held together by peptide bonds.

Proteins typically contain more than 40 amino acid units.

Most polypeptides shorter than about 40 amino acids in length do not fold into a well-defined protein structure, so biochemists use polymer length to distinguish proteins from polypeptides.

Hemoglobin contains of two chains of 142 amino acid units and two chains of 146 units folded into a complex three-dimensional structure.