Air flows out of the body during expiration because
A) intrapulmonary pressure is greater than atmospheric pressure.
B) intrapleural pressure is greater than intrapulmonary pressure.
C) atmospheric pressure is greater than intrapulmonary pressure.
D) intrapleural pressure is greater than atmospheric pressure.

Question

Quizplus · Accepted Answer

During expiration, the diaphragm and intercostal muscles relax, causing the thoracic cavity to decrease in volume. This increases the intrapulmonary pressure above atmospheric pressure, causing air to flow out of the lungs.

Air Flows Out of the Body During Expiration Because