Chloride ions leave the cell, and this recombines with the H plus to reform the carbonic acid. And then that basically breaks down into carbon dioxide. And the carbon dioxide then leaves the cell and it enters the alveolus. And so we see that the halding effect basically promotes the amount of CO2 that can be absorbed by the alveolus. So the red blood cells near the lungs filled with oxygen. The rise in oxygen causes them to bind to hemoglobin, which in turn decreases hemoglobin's affinity for carbon dioxide and H plus ions.