Mitochondrial membrane is impermeable to

Options

A. `NADH_(2)`
B. `CO_(2)`
C. CoQ
D. `O_(2)`

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which substance is impermeable to the mitochondrial membrane. This means we need to identify a substance that cannot easily pass through this membrane.

2. **Analyzing the Options**:
- **Option 1: NADH2**: This molecule is indeed not easily passable through the inner mitochondrial membrane. It plays a crucial role in cellular respiration and is involved in maintaining the proton gradient necessary for ATP production during oxidative phosphorylation.
- **Option 2: Carbon Dioxide**: This molecule is small and can easily diffuse across the mitochondrial membrane. Therefore, it is permeable.
- **Option 3: Coenzyme Q**: This is also permeable to the mitochondrial membrane. It is a key component in the electron transport chain and is involved in the process of oxidative phosphorylation.
- **Option 4: Oxygen**: Oxygen is a small molecule that can also easily pass through the mitochondrial membrane, making it permeable.

3. **Conclusion**: Based on the analysis, the only substance that is impermeable to the mitochondrial membrane is **NADH2**. Therefore, the correct answer is **Option 1**.

**Final Answer**: The mitochondrial membrane is impermeable to **NADH2**.

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