And that's because a fetal hemoglobin does not actually bind to two, three BPG. And so it is much more likely to actually attract other oxygen molecules and bind to those oxygen molecules. So we see that the maternal red blood cells have hemoglobin, the adult hemoglobin that binds oxygen much less readily than the fetal red blood cells that contain the fetal hemoglobin. And as a result, the oxygen will be much more likely to actually move from the blood of that mother and into the blood of that fetus that contains that fetal hemoglobin. Now, aside from this, there are two other factors that also facilitate the function of the placenta, facilitate the gas exchange process. So the movement of oxygen from the mother to the fetus can be facilitated by three factors.