And notice that in this particular example, the blue one is greater than our green one. So the next step is step number two. So once we separate that structure, once we separate these polypeptide chains, once we have the mixture of these two different types of polypeptide chains, the next question is how do we purify our mixture and isolate these two polypeptide chains into different compartments, into different beakers, for example? Well, we have to use some type of purification method now because in this case, the size of this is greater than the size of this. We can use gel electrophoresis. So.