The effects of a poison on actively respiring mitochondria are being studied to determine its mode of action.When the poison is added,every component of the electron transport chain is found to be in its reduced form based on spectroscopic analysis,and ATP production ceases entirely.It is reasoned that the poison is either blocking the final transfer of electrons to oxygen or is blocking the ATP synthase.Which of the following experiments will help unravel this dilemma?

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Adding an uncoupling agent along with the poison will help to distinguish between two possibilities as it will allow to bypass ATP synthase and electron transfer to oxygen. If the addition of the uncoupling agent can restore electron transport and reduce the component of the electron transport chain, it would mean that the poison is blocking ATP synthase and not the final transfer of electrons to oxygen. On the other hand, if no restoration is seen, it would mean the poison is blocking the final transfer of electrons to oxygen. Adding a second blocking agent or an artificial electron donor would not help to differentiate between these two possibilities.

The Effects of a Poison on Actively Respiring Mitochondria Are