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Inhibitors of Cellular Respiration

APBIO-GNNZDN

The electron transport chain (ETC), located in the inner membrane of the mitochondria, powers cellular respiration. As a final step in the process, cytochrome c oxidase transfers electrons to oxygen to form water.

Propose the outcome of an experiment where isolated mitochondria are treated with cyanide, an inhibitor of cytochrome c oxidase.

A

The electrons would reverse flow, moving toward the start of ETC.

B

Electron carriers would bypass cytochrome c oxidase and deliver electrons to a downstream acceptor.

C

Shutting down the ETC would not affect the Krebs cycle.

D

Electron carriers would remain reduced, cell damage and death would occur.