What is the space between the pleurae that contains pleural fluid called?

The space between the pleurae that contains pleural fluid is known as the pleural cavity. This cavity is essential for normal respiratory function, as the pleural fluid within it provides lubrication, allowing the pleura (the membranes surrounding the lungs and lining the thoracic cavity) to slide smoothly against each other during breathing. This reduces friction as the lungs expand and contract, facilitating efficient respiration.

The pleural cavity also plays a crucial role in maintaining negative pressure, which helps keep the lungs inflated. Understanding the function of the pleural cavity is important for grasping how respiratory mechanics work and the role of pleural fluid in mediating lung movement. The other terms mentioned do not accurately describe this specific space; for instance, the thoracic cavity encompasses all structures within the chest, while interpleural space refers to the same area but is not the standard terminology used in anatomy.