Energy required to form glucose from pyruvate is equivalent to

Options

A. 32 ATP
B. 16 ATP
C. 8 ATP
D. 4 ATP

Answer

To determine the energy required to form glucose from pyruvate, we need to analyze the process of glycolysis and the subsequent steps involved in gluconeogenesis, which is the formation of glucose from non-carbohydrate sources, including pyruvate.

### Step-by-Step Solution:

1. **Understanding Glycolysis**:
- Glycolysis is the metabolic pathway that converts glucose into pyruvate. This process occurs in the cytoplasm and results in the production of ATP and NADH.
- During glycolysis, one molecule of glucose (C6H12O6) is broken down into two molecules of pyruvate (C3H4O3).

2. **Energy Yield in Glycolysis**:
- The glycolytic pathway produces a net gain of 2 ATP molecules per glucose molecule. This means that while some ATP is consumed in the initial steps of glycolysis, the overall process yields 2 ATP.

3. **Gluconeogenesis**:
- Gluconeogenesis is the process by which glucose is synthesized from pyruvate. This process occurs mainly in the liver and requires energy input.
- To convert pyruvate back into glucose, gluconeogenesis uses ATP and GTP.

4. **Energy Requirement**:
- The conversion of two molecules of pyruvate into one molecule of glucose requires a total of 6 ATP equivalents (4 ATP and 2 GTP).
- Therefore, the energy required to form one molecule of glucose from pyruvate is equivalent to 6 ATP.

5. **Conclusion**:
- The energy required to form glucose from pyruvate is equivalent to 6 ATP.

### Final Answer:
The energy required to form glucose from pyruvate is equivalent to **6 ATP**.

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