Question

The partial pressure of oxygen in the alveolar air is:

• A. $45 \,mm$ of $Hg$
• B. $95 \,mm$ of $Hg$
• C. $104\, mm$ of $Hg$
• D. $110\, mm$ of $Hg$

Answer 1

Answer: (C)

$104\, mm$ of $Hg$

Answer 2

The partial pressure of oxygen in the alveolar air is 104 mm of Hg. It is the air present within the alveoli of the lungs. It is the average $P_{O_2}$ in the alveoli where the oxygen is exchanged with carbon dioxide during respiration.
The partial pressure of alveoli varies depending on the change in the altitude and some specific conditions.

So, the correct option is (C): 104 mm of Hg.