And notice that what that means is as the oxygen decreases, we can actually store even more carbon dioxide inside our blood because of what we discussed just a moment ago. So we see that a drop in the oxygen in the red blood cells next to the exercising tissue actually causes a leftward shift in the curve, which means more carbon dioxide can ultimately be stored inside the blood. And so the tissues will release more of the carbon dioxide because we can fit more of it into that blood plasma. Now, we can also use the halding effect to basically describe how the alveoli of the lungs are able to absorb more carbon dioxide from the blood plasma. So the Held in effect can also be used to explain how oxygen concentration affects carbon dioxide unloading into the alveoli of the lung. So let's take a look at the following diagram.