What forms an envelope between the lungs and the chest wall?

The pleurae are the membranes that form an envelope between the lungs and the chest wall. They consist of two layers: the visceral pleura, which directly covers the lungs, and the parietal pleura, which lines the chest cavity. This arrangement creates a pleural cavity filled with pleural fluid that serves to lubricate the surfaces, allowing the lungs to expand and contract smoothly during respiration.

The pleurae also play an essential role in maintaining lung function and ensuring that pressure changes during breathing facilitate air movement into and out of the lungs. This anatomical relationship is crucial for effective ventilation. In contrast, the serosa refers to a type of tissue that lines body cavities, the pericardium surrounds the heart, and the endothelium is a layer of cells lining blood vessels. Each of these structures has its own specific functions and locations within the body, distinct from the role of the pleurae in respiratory mechanics.