 In typical rig style, that was a molecular, like there was a lot of molecular process that happened in this lecture and a lot of moving parts and enzymes and little things that we can't actually see. Remembering where we are in the whole story is super important. I will tell you right now, I'm very deliberate about how I build the content and the order that we talk about things. And this lecture, if you are cozy with DNA replication, then DNA function, the next lecture is going to feel like, boom, I'm in. I totally get it and I'm totally good. Make sure you're cozy with this and make sure you're cozy with the big picture. The last thing I want to add for you is I want to give us a definition of the concept of a gene. When we talk about DNA, we often are talking about genetics and heredity and life cycles and reproduction. And we haven't given a definition of the word gene and where a gene is. And like I said, I've said this before, we're going to have three lectures, I think, on heredity, on how genes work and how we inherit the things that we do and why we look the way that we do. A gene, this is going to get us to the next lecture. A gene is a chunk of DNA that codes for a protein. And I will tell you that as we get into this stuff, it is so much crazier and more complicated than anything that we will talk about. But talking about it at the level that we will talk about it is huge because it gives you a foundation for understanding the really complicated stuff if you need to, but at least understanding having a foundation. Folks are battling over what consists of a gene and genes don't have to code for a protein. They can code for a functional mRNA molecule and I'm just going to hold off on that. I'm going to give you that information now and then I'm going to talk about it in the next lecture when we talk about protein function. I mean DNA function, which has a lot to do with proteins. So the gene is a piece of DNA that codes for a protein. And look, this is a chart that illustrates how many genes are on our chromosomes. And the light purple here is the number of genes on the chromosome. This is a weird graph because it has simultaneously, it has two different y-axis. The x-axis is just showing you the chromosomes. And you can see that we have all of our chromosomes, 1 through 22, and then we talked about these sex chromosomes, the x and the y, and what they are. So on the one hand, we have the number of genes listed. And then on the other hand, we have the total number of bases. Like how big are these genes? This is something to just sort of explore as you are or to think about as we start talking about how, like, why do we care about this stuff? And why are we learning all these crazy details? These genes are making proteins, not all your DNA codes for proteins. And that's another really interesting thing that we'll talk about. But chromosomes have lots of DNA, got to make copies of it. And that DNA can be captured in chunks that code for individual proteins. Okay. Has it been fun for you? I have a feeling that this lecture was profoundly long. I hope that you're still my friend. Okay. Bye-bye!