So a special enzyme we call carbonic anhydrase will combine carbon dioxide and water to form the carbonic acid molecule. And then the carbonic acid being a good acid, it will dissociate into H plus ions and the bicarbonate ions. And this is where the halding effect takes place. So according to the halding effect, if we decrease the concentration of oxygen in the red blood cell, so the amount of oxygen decreases because it travels into the tissue that exercising tissue. And so as this basically decreases, that increases the affinity of hemoglobin for the H plus ions. Now if we increase hemoglobin's affinity for H plus ions, what that means is the hemoglobin will begin to bind the H plus ions.