Which of the following best represents the partial pressures of all gases in the normally ventilated and perfused alveolus when breathing room air at sea level?

Question

Quizplus · Accepted Answer

Nitrogen is inert and plays no role in gas exchange. However, nitrogen does occupy space and exert pressure. According to Dalton's law, the partial pressure of alveolar nitrogen must equal the pressure it would exert if it alone were present. Thus, to compute the partial pressure of alveolar nitrogen, subtract the pressures exerted by all the other alveolar gases, as follows:

Which of the Following Best Represents the Partial Pressures of All