Metabolism USMLE Step 1 Practice Question
A 24-year-old laboratory worker is brought to the emergency department after sudden collapse during a chemical spill. He is tachypneic (RR 28/min) and confused. Vital signs show BP 102/68 mmHg, HR 118/min, temperature 37.2°C, and SpO2 98% on room air. Venous blood gas reveals elevated oxygen saturation with markedly elevated lactate (8.2 mmol/L). He denies chest pain. Which of the following components of oxidative phosphorylation is most likely inhibited?
Answer choices
- AComplex IVCorrect answer
- BComplex II
- CATP synthase
- DComplex I
- EComplex III
- FUbiquinone
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