And complex three actually consists of many polypeptide chains. In fact, we have eleven polypeptide chains that make up complex three. Now, the entire function, the entire purpose of complex three is to actually transfer those high energy electrons from QH two from Ubiquinol onto another carrier molecule, another electron carrier used by the electron transport chain known as cytochrome C. And so in this lecture, we're going to discuss the details of how this transfer actually takes place. So let's begin by focusing on the three major components that you should be familiar with that define on complex three. The first one that you should know is cytochrome C one. And this is not the same thing as cytochrome C, even though they're both cytochrome molecules.