Name the first molecule pyruvic acid is converted to by a dehydrogenese enzyme.

Answer

**Step-by-Step Solution:**

1. **Understanding Pyruvic Acid**: Pyruvic acid is the end product of glycolysis, which occurs when glucose is broken down to extract energy. Each glucose molecule results in two molecules of pyruvic acid.

2. **Conditions of Oxygen Supply**: The fate of pyruvic acid depends on the availability of oxygen. If oxygen is present (aerobic conditions), pyruvic acid will undergo further processing.

3. **Oxidative Decarboxylation**: In aerobic conditions, pyruvic acid undergoes a process called oxidative decarboxylation. This is a crucial step in cellular respiration.

4. **Role of Dehydrogenase Enzyme**: The enzyme responsible for this conversion is called pyruvic dehydrogenase. It catalyzes the reaction that converts pyruvic acid into another molecule.

5. **Formation of Acetyl Coenzyme A**: The first molecule that pyruvic acid is converted to by the dehydrogenase enzyme (pyruvic dehydrogenase) is acetyl coenzyme A (acetyl CoA). This molecule then enters the Krebs cycle for further energy production.

**Final Answer**: The first molecule pyruvic acid is converted to by a dehydrogenase enzyme is acetyl coenzyme A (acetyl CoA).

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