During inspiration, muscular contraction of the diaphragm causes air to move into the lung.The mechanism that drives air movement during inspiration results in a(n):
A) decrease in intra-alveolar pressure and shortening of the rib cage.
B) decrease in the size of the thorax and alveolar expansion.
C) increase in the size of the thorax and decrease in intrapleural pressure.
D) increase in atmospheric pressure and intrapleural pressure.

Question

Quizplus · Accepted Answer

During inspiration, the diaphragm contracts and moves downward, increasing the size of the thoracic cavity. This expansion decreases intrapleural pressure, allowing air to flow into the lungs as the pressure inside the alveoli becomes lower than atmospheric pressure.

During Inspiration, Muscular Contraction of the Diaphragm Causes Air to Move