If the partial pressure of oxygen in the alveolar air is 104 mmHg, approximately what will be the concentration of dissolved oxygen in the blood leaving the pulmonary capillaries?

C: Oxygen will continue to diffuse from the alveoli across the respiratory membrane into the blood while the concentration gradient exists. The gradient will exist until the plasma concentration reaches 104 mmHg. In reality blood travelling away from the alveoli will be at slightly less than 104 mmHg as some oxygen will have been used by the lung tissue.