Lung is enclosed by `"_____________"` membrane.

Answer

To answer the question "Lung is enclosed by _____________ membrane," we can follow these steps:

1. **Identify the Structure**: Understand that the lungs are vital organs involved in the process of respiration. They are located in the thoracic cavity.

2. **Membrane Surrounding the Lungs**: Recognize that the lungs are not just floating in the thoracic cavity; they are surrounded by a specific type of membrane that provides protection and facilitates their function.

3. **Name of the Membrane**: The membrane that encloses the lungs is known as the "pleural membrane." This membrane consists of two layers: the visceral pleura, which is attached to the lungs, and the parietal pleura, which lines the chest wall.

4. **Function of the Pleural Membrane**: The pleural membrane serves several important functions, including reducing friction between the lungs and the chest wall during breathing movements and helping to maintain the pressure gradient necessary for lung inflation.

5. **Final Answer**: Therefore, the blank in the question can be filled with "pleural membrane."

**Final Answer**: Lung is enclosed by **pleural membrane**.

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