Proteins
Proteins are polymers that are made up of amino acid monomers. All amino
acids have two functional groups in common—an amino group (remember,
−NH 2 ) and a carboxyl group (−COOH). This means that they are amphoteric and
can act as either an acid or a base. All of the 20 different amino acid monomers
that make up proteins differ in their side chain or R group. Chains of linked
amino acids are known as polypeptides, and proteins are formed by the folding
of the polypeptide chains (and oftentimes the association of one or more
polypeptide chains). Recall our discussion of catalysts: All enzymes, which are
biological catalysts that speed up the rate of nearly all cellular reactions, are
proteins.
Okay, that’s it for organic chemistry—let’s briefly review what you’ll need to
know about environmental chemistry and then wrap up this chapter!