The plasma membrane redox system is an aspect of the cell membrane that exports unneeded hydrogen atoms from redox reactions. It is useful when in the process of aging the mitochondria's ability to perform oxidative phosphorylation is compromised through DNA damage to mitochondrions. As oxidative phosphorylation is what normally converts NADH back to NAD+ for use in other cellular processes, when it can no longer keep up, the cell undergoes a redox reaction to prevent toxic buildup of NADH molecules and to replenish NAD+ stores.
While this reaction is beneficial for the cell, it may have negative effects on the overall wellbeing of multicellular organisms due to the Hydrogen ions released into the intracellular fluids, if they are not safely eliminated.
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