Final answer:
Fatty acids, amino acids, and nucleic acids can all increase the concentration of hydrogen ions by acting as acids or bases depending on the pH level, influencing the pH balance and potentially leading to changes in macromolecule structures and cellular functions.
Step-by-step explanation:
Fatty acids, amino acids, and nucleic acids can affect the concentration of hydrogen ions (H+) in various ways, ultimately influencing pH levels. Acidity is correlated with the concentration of H+, where environments with pH values below 7.0 are acidic and those above 7.0 are basic. Amino acids, for instance, can act as buffers. They can capture an H+ ion from an added acid to maintain pH, as seen in the behavior of zwitterions. Nucleic acids contribute to acidity through the ionization of the acidic hydrogen atoms on their phosphate groups, whereas the breakdown of fatty acids in a basic environment can result in an increase in H+ ions.
In the case of proteins, which are made of amino acids, moderate changes in pH can affect their structure and function due to the alteration in hydrogen bonding and ionization of the amino-acid functional groups. This can lead to destabilization and denaturation of proteins. Also, basic amino acids like histidine can accept H+ ions when the pH is below their pKa value, increasing acidity. Similarly, the increasing strength of acids across a row in the periodic table correlates with the polarity and electronegativity of the nonmetal atom bonded to hydrogen, reflecting variations in the ease of proton (H+) release.