Which Pressure Remains Negative Throughout the Respiratory Cycle

Question

Which pressure remains negative throughout the respiratory cycle?
A) intrapulmonary
B) intrapleural
C) intra-alveolar
D) atmospheric
E) intrapulmonary and intra-alveolar

Accepted Answer

Intrapleural pressure is always negative throughout the respiratory cycle due to the opposing forces of the elastic recoil of the lungs and the chest wall. This negative pressure helps to keep the lungs inflated and allows for proper gas exchange to occur. In contrast, intrapulmonary and intra-alveolar pressures fluctuate during the respiratory cycle. Atmospheric pressure remains relatively constant unless there are changes in altitude or weather.