And so as the electron travels from the risky sensor to the Cytochrome C one, it actually attaches onto the iron atom of the Heme group, and so it is reduced. Now, the electron travels from the Hen group and ultimately ends up on the Heme group of Cytochrome C. And notice, only a single electron can actually bind onto Cytochrome C. So this is the major difference between Cytochrome C electron carrier and the Ubiquinone electron carrier. Ubiquinone is able to actually bind two electrons, but Cytochrome C can only bind a single electron. And that's exactly why the second electron cannot follow this same pathway. It has to follow a different pathway. And by following this different pathway, what we ultimately accomplish by the second electron pathway is we're able to actually recycle that electron and use that electron in a future process, as we'll see in more detail in just a moment.