Which of the following statements are true about pressure differences in the upright lung?
1) P_pl increases from lung apex to base.
2) The apical alveoli resting volume is less than at the base.
3) The transpulmonary pressure gradient is greatest at the apex.

Question

Quizplus · Accepted Answer

1) P_pl (pressure at the alveolar level) increases from lung apex to base due to the added weight of the more superior tissue causing increased compression and higher pressure at the bottom. 2) The apical alveoli resting volume is less than at the base due to the effects of gravity causing more expanded alveoli at the bottom. 3) The transpulmonary pressure gradient (the difference in pressure between the inside of the lung and the outside) is greatest at the apex due to the decreased lung volume causing less pressure inside the lung and the weight of the tissue pressing on the outside causing more pressure outside the lung.

Which of the Following Statements Are True About Pressure Differences