In Zone 2 of the lungs, the relationship of pressures is:

In Zone 2 of the lungs, the pressures follow a specific relationship that reflects the dynamics of blood flow within the pulmonary capillaries. In this zone, the arterial pressure is greater than the alveolar pressure, which allows for blood to flow through the capillaries. The venous pressure, however, is lower than the alveolar pressure but still higher than the arterial pressure, which facilitates the movement of blood into the venous system once it has passed through the capillaries.

To clarify the correct response, the fact that arterial pressure exceeds alveolar pressure ensures that there is adequate perfusion of blood through the pulmonary capillaries, allowing for optimal gas exchange. The subsequent relationship where venous pressure is less than alveolar pressure means that the pressure gradient favors blood leaving these capillaries towards the veins, facilitating efficient circulation.

This relationship is characteristic of Zone 2, where blood flow is determined by the differences in pressures and supports the overall function of the lungs during respiration. It highlights the regulation of blood flow in accordance with the mechanical properties of the lung and the influence of gravity on pulmonary blood flow distribution.