And that tells us that their affinity for oxygen, which will also increase, which is what we see happening in nature. So if we add one more oxygen, this will basically change our shape. And this nearby structure will also change its polypeptide chain. If we add one more oxygen, we get this. And finally, if this one is filled, we get the r state. So the major difference between the concerted model and the sequential model is in the concerted model, we only have either the t state or the r state.