Outer pleural membrane is in close contact with

Options

A. Surface of lungs
B. Thoracic cavity
C. Both (1) & (2)
D. Alveoli

Answer

To answer the question "Outer pleural membrane is in close contact with," we will analyze the options provided and the structure of the pleural membranes.

### Step-by-Step Solution:

1. **Understanding the Pleural Membrane**:
- The pleural membrane consists of two layers: the outer pleural membrane (also known as the parietal pleura) and the inner pleural membrane (also known as the visceral pleura).
- The outer pleural membrane lines the thoracic cavity, while the inner pleural membrane is in direct contact with the surface of the lungs.

2. **Analyzing the Options**:
- **Option 1: Surface of Lungs**: This option refers to the inner pleural membrane, which is indeed in contact with the lungs. Therefore, this option is incorrect for the outer pleural membrane.
- **Option 2: Thoracic Cavity**: The outer pleural membrane is in close contact with the thoracic cavity. This option is correct.
- **Option 3: Both 1 and 2**: Since option 1 is incorrect, this option cannot be correct.
- **Option 4: Alveoli**: Alveoli are the tiny air sacs in the lungs where gas exchange occurs, but they are not in direct contact with the pleural membranes. Therefore, this option is also incorrect.

3. **Conclusion**:
- The outer pleural membrane is in close contact with the thoracic cavity. Thus, the correct answer to the question is **Thoracic Cavity**.

### Final Answer:
**The outer pleural membrane is in close contact with the thoracic cavity.**

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