Changes

===Pleural Membrane Function===

===Pleural Membrane Function===

*The Pleural Cavity is filled with a small amount of serous fluid which forms a thin film of liquid between the pleural layers. This is vital in that in prevents separation of the two pleural layers and lubricates the surface, so the [[Lungs - Anatomy & Physiology|lungs]] can move easily within the thoracic cavity.

*The Pleural Cavity is filled with a small amount of serous fluid which forms a thin film of liquid between the pleural layers. This is vital in that it prevents separation of the two pleural layers and lubricates the surface, so the [[Lungs - Anatomy & Physiology|lungs]] can move easily within the thoracic cavity.

*The Pleural Fluid also provides surface tension, keeping the [[Lungs - Anatomy & Physiology|lung]] suitably close to the wall of the thorax, despite the the lungs not being directly fixed to it. The pleurae thus allow the volume of the [[Lungs - Anatomy & Physiology|lungs]] to change with the volume of the thoracic cavity, enabling [[Ventilation - Anatomy & Physiology|Ventilation]].

*The Pleural Fluid also provides surface tension, keeping the [[Lungs - Anatomy & Physiology|lung]] suitably close to the wall of the thorax, despite the the lungs not being directly fixed to it. The pleurae thus allow the volume of the [[Lungs - Anatomy & Physiology|lungs]] to change with the volume of the thoracic cavity, enabling [[Ventilation - Anatomy & Physiology|Ventilation]].

*The left and right pleural sacs are separate so that in the event of one being punctured, the other [[Lungs - Anatomy & Physiology|lung]] can continue to function effectively.

*The left and right pleural sacs are separate so that in the event of one being punctured, the other [[Lungs - Anatomy & Physiology|lung]] can continue to function effectively.