Question

Which of the following reactions has a sufficiently large free-energy change to enable it to be used, in principle, to provide the energy needed to synthesize one molecule of ATP from ADP and Pi under standard conditions? See Table Q14-47. Recall that

ΔG° = -n (0.023) ΔE0′, and
ΔE0′ = E0′ (acceptor) - E0′ (donor).
(a) the reduction of a molecule of pyruvate by NADH
(b) the reduction of a molecule of cytochrome b by NADH
(c) the reduction of a molecule of cytochrome b by reduced ubiquinone
(d) the oxidation of a molecule of reduced ubiquinone by cytochrome c

Answer 1

The oxidation of a molecule of reduced ubiquinone by cytochrome c has a sufficiently large free-energy change to enable it to provide the energy needed to synthesize one molecule of ATP from ADP and Pi under standard conditions. Therefore, option (d) is the correct answer.

Step-by-step explanation:

The reaction that has a sufficiently large free-energy change to enable it to provide the energy needed to synthesize one molecule of ATP from ADP and Pi under standard conditions is option (d): the oxidation of a molecule of reduced ubiquinone by cytochrome c.

In this reaction, the reduced ubiquinone (QH2) is oxidized by cytochrome c, resulting in the transfer of electrons. This electron transfer releases energy, which can be used to synthesize ATP.

Therefore, option (d) is the correct answer.