The force that moves air into and out of the lungs is the difference in pressure between the atmosphere and alveolus.

Question

Quizplus · Accepted Answer

The movement of air into and out of the lungs (inhalation and exhalation) is driven by the difference in pressure between the atmosphere and the alveoli. When the pressure inside the alveoli is lower than the atmospheric pressure, air flows into the lungs (inhalation). Conversely, when the pressure inside the alveoli is higher than the atmospheric pressure, air flows out of the lungs (exhalation).

The Force That Moves Air into and Out of the Lungs