If the partial pressure of oxygen in alveolar air is 100 mmHg and the concentra- tion of dissolved oxygen in capillary blood arriving at the alveoli is 40 mmHg, what will be the concentration of dissolved oxygen in blood leaving the alveoli? A. 140 mmHg B. 100 mmHg C. 70 mmHg D. 60 mmHg
Option B. Oxygen in alveolar air will diffuse down its concentration gradi- ent into capillary blood till blood withinside the capillary is also at a 100 mmHg. After this there may be no concentration gradient to effect a net diffusion.
