Cyanide Gas is Lethal Because It

Question

Cyanide gas is lethal because it
A) inhibits the kinase that phosphorylates ATP.
B) inhibits the ATP synthase.
C) blocks substrate-level phosphorylation.
D) blocks the final electron acceptor in the ETS.
E) binds NAD preventing it from being reduced.

Accepted Answer

Cyanide gas blocks the final electron acceptor in the electron transport chain (ETS), which is oxygen. This prevents the production of ATP from oxidative phosphorylation, leading to cellular respiration failure and eventually death.