Muscle tissues make lactate from pyruvate to do which of the following?

• A. Speed up the rate of glycolysis
• B. Get rid of pyruvate produced by glycolysis
• C. Utilize the energy in pyruvate
• D. Produce additional CO₂
• E. Regenerate NAD⁺

Answer: (E)

Verified step by step guidance

1. Understand that glycolysis is a process that breaks down glucose into pyruvate, producing ATP and NADH in the process.
2. Recognize that during anaerobic conditions (lack of oxygen), the electron transport chain cannot function effectively, leading to a buildup of NADH.
3. Realize that for glycolysis to continue, NAD+ must be regenerated from NADH, as NAD+ is a necessary cofactor for glycolysis.
4. Identify that converting pyruvate to lactate is a way to regenerate NAD+ from NADH, allowing glycolysis to continue producing ATP even in the absence of oxygen.
5. Conclude that the primary reason muscle tissues convert pyruvate to lactate is to regenerate NAD+, ensuring the continuation of ATP production through glycolysis under anaerobic conditions.