Changes

==Introduction==

==Introduction==

Ventilation is the movement of air into and out of the [[Lungs - Anatomy & Physiology|lungs]]. Air moves from high pressure to low pressure with the rate of flow being proportional to the pressure difference. As environmental pressure is generally constant, the [[Cardiorespiratory System - Anatomy & Physiology|respiratory system]] must change it's internal pressure to maintain air flow.

Ventilation is the movement of air into and out of the [[Lungs - Anatomy & Physiology|lungs]]. Air moves from high pressure to low pressure with the rate of flow being proportional to the pressure difference. As environmental pressure is generally constant, the [[Cardiorespiratory System Overview - Anatomy & Physiology|respiratory system]] must change it's internal pressure to maintain air flow.

The lungs are not fixed to the thoracic wall but follow the changing volume of the thoracic cavity thanks to the [[Pleural cavity and membranes - Anatomy & Physiology#Pleural Membranes|Pleura]].

The lungs are not fixed to the thoracic wall but follow the changing volume of the thoracic cavity thanks to the [[Pleural cavity and membranes - Anatomy & Physiology#Pleural Membranes|Pleura]].