How many 'H_2 O' molecule are involved in oxidation decarboxylation and Kreb's ctcle?

Options

A. 1
B. 4
C. 5
D. 6

Answer

To determine how many water (H₂O) molecules are involved in oxidation, decarboxylation, and the Krebs cycle, we can break down the process step by step.

### Step-by-Step Solution:

1. **Understanding the Processes**:
- **Oxidation**: This refers to the process of removing electrons from a molecule, often involving the addition of oxygen or the removal of hydrogen.
- **Decarboxylation**: This is the removal of a carboxyl group (COOH) from a molecule, releasing carbon dioxide (CO₂).
- **Krebs Cycle**: Also known as the citric acid cycle, it is a series of chemical reactions used by all aerobic organisms to generate energy.

2. **Analyzing the Krebs Cycle**:
- The Krebs cycle involves several key reactions where water molecules are both consumed and produced.
- Specifically, during the conversion of certain intermediates, water is added or removed.

3. **Counting Water Molecules**:
- In the Krebs cycle:
- When isocitrate is converted to alpha-ketoglutarate, one water molecule is used.
- When alpha-ketoglutarate is converted to succinyl-CoA, another water molecule is involved.
- When fumarate is converted to malate, one water molecule is added.
- When malate is converted back to oxaloacetate, one water molecule is involved.
- This totals to **4 water molecules** being involved in the Krebs cycle.

4. **Conclusion**:
- Therefore, when considering oxidation, decarboxylation, and the Krebs cycle, the total number of water molecules involved is **4**.

### Final Answer:
The total number of water (H₂O) molecules involved in oxidation, decarboxylation, and the Krebs cycle is **4**.

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