Khan Academy ETC uncoupling

[663697]

When taken in very high doses, aspirin causes a fever. What is NOT a plausible mechanism for this effect at the level of the electron transport chain?

a) Aspirin is a site-specific inhibitor of one of the electron transport chain proteins. correct answer
b) Aspirin increases translation and transcription of UCP channels.
c) Aspirin binds to and sequesters protons in the inter-membrane space in the mitochondria.
d) Aspirin makes the outer mitochondrial membrane more permeable

Why would C and D be plausible mechanisms for the heat generated? The passage says that in order to generate heat the protons need to move down their gradient through UCP's into the mitochondrial matrix. If the outer membrane was made more permeable, wouldn't the protons be able to diffuse through it, reducing the amount of heat generated? Similarly, if aspirin sequesters protons in the inter-membrane space, wouldn't this reduce the amount of free H+ available to re-enter the matrix through UCP's?

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[aldol16]

Protons diffusing through the membrane causes heat generation just like a proton decoupler would. Because of the proton gradient, there's a lot of potential energy stored in that gradient. Protons flowing down the gradient converts that potential energy into other forms of energy, such as heat and work. Usually, the protons flow through ATP synthase and generate useful work. The rest of the energy is released as work. When the protons just flow through without producing any meaningful work, all of the potential energy stored there is converted into heat (instead of heat and work).