Answer and explanation

Correct answer: C. Pyruvate is decarboxylated and oxidised to form acetyl coenzyme A, with reduced NAD produced

  1. Step 1: Pyruvate enters the mitochondrial matrix. Step 2. It loses CO2 and hydrogen, forming acetyl CoA and reduced NAD. Answer: Pyruvate is decarboxylated and oxidised to form acetyl coenzyme A, with reduced NAD produced. Why not the others: splitting glucose is glycolysis; the Krebs cycle (in the matrix) oxidises acetyl CoA; lactate formation is anaerobic.

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