Q. Which of the following statements is not true?
A) The partial pressure of oxygen in deoxygenated blood is 40 mm Hg
B) The partial pressure of oxygen in oxygenated blood is 95 mm Hg
C) The partial pressure of oxygen in the alveolar air is 104 mm Hg
D) The partial pressure of carbon dioxide in deoxygenated blood is 95 mm Hg
Explanation
Each gas in the mixture exerts a part of the total pressure proportional to its concentration, $ie,$ the partial pressure. This is denoted as $p,\ e.g.,\ p_{O_{2}},\ \ p_{CO_{2}}.\$ Partial pressure (mm Hg) of respiratory gases [table] Gas | Inspi-red Air | Alve-olar Air | Deoxyg-enated Blood | Oxyge-nated Blood | Exp-ired Air ; O₂ | 158 | 100 | 40 | 95 | 116 ; CO₂ | 0.3 | 40 | 46 | 40 | 32 [/table]
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.