What is the pleura?

The pleura is indeed a double-layered membrane that surrounds each lung. This structure is crucial for protecting the lungs and facilitating their movement during respiration. The two layers of the pleura are known as the visceral pleura, which directly covers the lung surface, and the parietal pleura, which lines the inner wall of the thoracic cavity. The space between these two layers, called the pleural cavity, contains a small amount of pleural fluid that reduces friction as the lungs expand and contract during breathing. This anatomical feature is vital for creating the pressure differences needed for air to flow into and out of the lungs, thus playing an essential role in the respiratory process. Understanding the function and structure of the pleura can help in recognizing its importance in respiratory health and disease.