What is the primary function of the parietal pleura?

What is the primary function of the parietal pleura?

• A. To line the thoracic cavity
• B. To facilitate gas exchange
• C. To provide a barrier against infections
• D. To secrete surfactant

Answer: (A)

The primary function of the parietal pleura is to line the thoracic cavity. This double-layered membrane plays a crucial role in the respiratory system by providing a smooth surface that allows the lungs to expand and contract without friction against the wall of the thoracic cavity. It also helps to create a pressure gradient that is essential for proper lung inflation. The parietal pleura is attached to the inner surface of the chest wall and the upper surface of the diaphragm, which is key for separating the thoracic cavity from the abdominal cavity. While other components of the pleural space, such as the visceral pleura, participate in lung function, the specific role of the parietal pleura is to create a lining that supports the mechanics of breathing. The choices related to facilitating gas exchange, providing a barrier against infections, and secreting surfactant pertain to different structures or functions within the respiratory system. Gas exchange occurs in the alveoli, barriers against infections are typically provided by immune mechanisms rather than pleural layers, and surfactant is secreted by the alveolar cells rather than the pleura itself. Thus, the parietal pleura's primary and most significant role is indeed to line the thoracic cavity.

The primary function of the parietal pleura is to line the thoracic cavity. This double-layered membrane plays a crucial role in the respiratory system by providing a smooth surface that allows the lungs to expand and contract without friction against the wall of the thoracic cavity. It also helps to create a pressure gradient that is essential for proper lung inflation. The parietal pleura is attached to the inner surface of the chest wall and the upper surface of the diaphragm, which is key for separating the thoracic cavity from the abdominal cavity.

While other components of the pleural space, such as the visceral pleura, participate in lung function, the specific role of the parietal pleura is to create a lining that supports the mechanics of breathing. The choices related to facilitating gas exchange, providing a barrier against infections, and secreting surfactant pertain to different structures or functions within the respiratory system. Gas exchange occurs in the alveoli, barriers against infections are typically provided by immune mechanisms rather than pleural layers, and surfactant is secreted by the alveolar cells rather than the pleura itself. Thus, the parietal pleura's primary and most significant role is indeed to line the thoracic cavity.