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In: Chemistry

In the citric acid cycle, malate is oxidized to oxaloacetate by the enzyme malate dehydrogenase, which...

In the citric acid cycle, malate is oxidized to oxaloacetate by the enzyme malate dehydrogenase, which uses NAD+ as an electron acceptor. In cells, the ratio of [NAD+]/[NADH] is kept very high. Given the following standard reduction potentials, explain why it is so important for cells to maintain this ratio. Justify your answer with words, equations and diagrams.

oxaloacetate + 2H+ + 2e- -> malate

E°red= -0.166 V

NAD+ + H+ + 2e- > NADH

E°red= -0.320

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