Previously, we focused on the oxygen binding curve of myoglobin and hemoglobin. And we saw that in the case of myoglobin, myoglobin binds oxygen very strongly. It has a very high affinity for oxygen, and it binds oxygen in a noncooperative fashion. On the other hand, we saw that the shape for our hemoglobin curve was a sigmoidal shape. And this, this describes the cooperative behavior of hemoglobin. So even though hemoglobin has a lower affinity for oxygen than myoglobin, hemoglobin is able to bind oxygen in a cooperative fashion.