They produce an excess of two, three BPG molecules. These molecules can pass along the membrane into the matrix, and then eventually, they end up within the blood plasma and move into the red blood cells. Now, once the two, three BPG are inside the red blood cells, they go on to directly interact with hemoglobin. They bind to a special side between the two beta subunes of hemoglobin, and they create a conformational change. And by binding to hemoglobin and creating that conformational change, they decreased a lower vicinity of hemoglobin for oxygen. And once again, this allows for more oxygen to actually be unloaded, and more oxygen ends up in the cells of our tissue.