B1.2.2

• To form a dipeptide, two amino acids are linked by a condensation reaction.
• Polypeptides can contain any number of amino acids. They are the main component of protein.
• Amino acids are linked with peptide bonds. These are C-N bonds formed by a condensation reaction between the amine group of one amino acid and the carboxyl group of another.
• The condensation reaction is catalysed in cells by ribosomes.