Mitochondrial membranes divide its lumen into two ____ compartments.

Answer

**Step-by-Step Text Solution:**

1. **Understanding Mitochondrial Structure**: Mitochondria are organelles known as the powerhouses of the cell. They have a unique structure consisting of two membranes: an outer membrane and an inner membrane.

2. **Membrane Division**: The outer membrane surrounds the mitochondria, while the inner membrane folds inward to create structures known as cristae. This folding is crucial for the function of mitochondria.

3. **Formation of Compartments**: The presence of these two membranes divides the mitochondrial lumen into two distinct aqueous compartments:
- **Outer Compartment**: This is the space between the outer membrane and the inner membrane.
- **Inner Compartment (Matrix)**: This is the space enclosed by the inner membrane, which contains the matrix.

4. **Function of Compartments**: Each compartment has its own set of enzymes and plays a specific role in cellular respiration. The inner compartment is particularly important as it contains enzymes for the electron transport chain and the matrix, where the Krebs cycle occurs.

5. **Final Answer**: Therefore, the correct answer to the question is that the mitochondrial membranes divide its lumen into two **aqueous** compartments.

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