Answer:
See the explanation below. Thanks!
Explanation:
The structure of an amino acid allows it to act as both an acid and a base. An amino acid has this ability because at a certain [tex]pH[/tex] value (different for each amino acid) nearly all the amino acid molecules exist as zwitter-ions. If acid is added to a solution containing the zwitter-ion, the carboxylate group captures a hydrogen ([tex]H^+[/tex]) ion, and the amino acid becomes positively charged. If base is added, ion removal of the [tex]H^+[/tex] ion from the amino group of the zwitter-ion produces a negatively charged amino acid. In both circumstances, the amino acid acts to maintain the pH of the system—that is, to remove the added acid [tex](H^+)[/tex] or base [tex](OH^-)[/tex] from solution.
