Which of the following events accompanies the conversion of pyruvate to acetyl CoA before the citric acid cycle?

• A. Formation of CO₂ and synthesis of ATP
• B. Release of CO₂ and release of coenzyme A
• C. Removal of coenzyme A
• D. Regeneration of NAD⁺
• E. Release of CO₂ and synthesis of NADH

Answer: (E)

Verified step by step guidance

1. Understand the context: Pyruvate conversion to acetyl CoA is a crucial step in cellular respiration, linking glycolysis to the citric acid cycle.
2. Identify the key components involved: Pyruvate, acetyl CoA, CO2, NAD+, and NADH are involved in this conversion process.
3. Recognize the chemical reaction: Pyruvate undergoes oxidative decarboxylation, where it loses a carbon atom in the form of CO2.
4. Consider the role of NAD+: During this conversion, NAD+ is reduced to NADH, capturing high-energy electrons.
5. Conclude the process: The conversion results in the release of CO2 and the formation of acetyl CoA, with NADH being synthesized, not ATP.