Respiratory System

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Tab 3

If the pulmonary capillary partial pressure of a gas equilibrates with that in the alveolus before the blood leaves the capillary (assume the gas is diffusing from the alveolus to the pulmonary capillary):

its transfer is said to be perfusion limited.

its transfer is said to be diffusion limited.

increasing the cardiac output will not increase the amount of the gas diffusing across the alveolar-capillary barrier.

increasing the alveolar partial pressure of the gas will not increase the amount of the gas diffusing across the alveolar-capillary barrier.

recruiting additional pulmonary capillaries will not increase the amount of the gas diffusing across the alveolar-capillary barrier.

Answer

Which of the following statements concerning alveolar pressure is/are correct?

Alveolar pressure is lower than atmospheric pressure during a normal negative-pressure inspiration.

Alveolar pressure is greater than atmospheric pressure during a forced expiration.

Alveolar pressure equals the sum of the intrapleural pressure plus the alveolar elastic recoil pressure.

Alveolar pressure equals atmospheric pressure at the end of a normal tidal expiration.

All of the above.

The correct answer is E. You answered E.

Content 3

Study Questions