Metabolism USMLE Step 1 Practice Question
A 30-year-old male has been fasting for religious reasons for several days. His blood glucose level is now about 60% of its normal value, but he does not feel lightheaded because his brain has reduced its need for serum glucose by using which of the following substances as an alternate energy source?
Answer choices
- ABeta-hydroxybutyrateCorrect answer
- BApoprotein B
- CBeta-carotene
- DC-reactive protein
- ECoenzyme A
- FFree fatty acids transported across the blood-brain barrier for direct oxidation
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