The inner compartment of mitochondria is called-

Answer

**Step-by-Step Solution:**

1. **Understanding Mitochondria Structure**: Mitochondria are known as the powerhouse of the cell and are characterized by having a double membrane structure, which includes an outer membrane and an inner membrane.

2. **Identifying the Inner Compartment**: The space enclosed by the inner membrane of the mitochondria is referred to as the inner compartment.

3. **Naming the Inner Compartment**: This inner compartment is specifically called the "mitochondrial matrix."

4. **Functions of the Matrix**: The mitochondrial matrix contains mitochondrial DNA and enzymes that are crucial for the Krebs cycle (TCA cycle), which is essential for ATP production through cellular respiration.

5. **Conclusion**: Therefore, the correct answer to the question regarding the inner compartment of mitochondria is "matrix."

**Final Answer**: The inner compartment of mitochondria is called the **matrix**.

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