As the volume of the thoracic cavity increases due to the contraction of the muscles of inspiration,what occurs in the lungs and alveoli?
A)lung and alveolar volumes increase and intrapulmonary pressure increases
B)lung and alveolar volumes increase and intrapulmonary pressure decreases
C)lung and alveolar volumes decrease and intrapulmonary pressure increases
D)lung and alveolar volumes decrease and intrapulmonary pressure decreases

Question

Quizplus · Accepted Answer

As the volume of the thoracic cavity increases during inspiration, the lung and alveolar volumes also increase. This increase in volume causes the intrapulmonary pressure to decrease, allowing air to flow into the lungs along the pressure gradient from high to low pressure. Therefore, choice B is the correct answer.

As the Volume of the Thoracic Cavity Increases Due to the Contraction