Citric Acid Cycle And Oxidative Phosphorylation Practice Test

A 25-year-old sprinter undergoes a muscle biopsy as part of a research study on exercise physiology. The skeletal muscle cells are analyzed for their mechanism of transferring reducing equivalents from glycolysis into the mitochondria. These cells primarily utilize the glycerol-3-phosphate shuttle.

A 62-year-old man with a history of chronic alcohol use disorder is brought to the emergency department with confusion, ataxia, and nystagmus. His symptoms are attributed to a deficiency in thiamine. Thiamine is a crucial cofactor for an enzyme in the citric acid cycle that is structurally and mechanistically similar to the pyruvate dehydrogenase complex.