How can amino acids be use to maintain the blood pH?

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 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 () ion, and the amino acid becomes positively charged. If base is added, ion removal of the 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 or base from solution.

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explanation:

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