In the citric acid cycle, the enzyme succinate dehydrogenase catalyzes a reversible reaction using FAD/FADH2 as an oxidizing/red
ucing agent. Which of the following statements best explains how the redox component of this reaction contributes to the reaction's ability to be reversible under cellular conditions? A. FAD has no reduction potential when it is enzyme-bound.
B. FAD can be reduced by the sequential addition of one hydrogen at a time.
C. FAD/FADH2 is covalently bound to succinate dehydrogenase.
D. The change in the biochemical standard reduction potential is small.
The statement which best explains how the redox component of this reaction contributes to the reaction's ability to be reversible under cellular conditions is; <em>Choice D: The change in the biochemical standard reduction potential is small.</em>
Discussion:
A reversible process is one in which the system and environment can be restored to exactly the same initial states that they were in prior to when the process occurred, if we go backward along the path of the process.
However, the necessary condition for a reversible process is therefore the quasi-static requirement.
The quasi-static requirement in this case is that the change in the biochemical standard reduction potential is small.
The hormone ADH operates by negative feedback mechanism in that when the body's tissues lack water, it causes the nephrons to retain water to prevent the body's tissues drying out.
