And what the sigmoidal shape curve basically means is the binding affinity of hemoglobin for oxygen is much smaller than that for myoglobin. So we said earlier that a concentration of only 2 mercury is needed to actually bind 50% of that myoglobin to oxygen. Now, in the case of hemoglobin, if we draw a straight line from the 50% mark, from the 0.5 mark, and we draw a vertical line down, this will give us a partial pressure of about 26 mercury. So a concentration of 26 mercury is needed for exactly half of those hemoglobin molecules to become saturated to bind that oxygen, compared to the 2 mercury for the myoglobin. And what that means is that hemoglobin binds oxygen much less likely than the myoglobin. And so it has a lower affinity for oxygen than my globin.