 Hi, doggies. We're here today. This is really exciting because we're here to talk about our first living thing. We've been dealing with science. We've been dealing with chemistry. We've been talking about, dude, what is this class going to be all about? Well, the study of life begins with the study of cells. Now, please do not forget that the reason why we looked at chemistry is because we have to know what cells are made out of, especially today. We're going to look at the cell itself, but in order for a cell to function as a living organism, it has to have parts that totally work, and those parts are smaller, and the parts technically are not alive. So we're going to look at what is inside a cell, and none of the stuff inside a cell is alive, but the cell itself has the emergent property of life. There are so many different kinds of cells. Studying the cell is really, really interesting, and we could spend the entire semester studying different kinds of cells. So check this out. What is this? This is like, well, first of all, this is a cell that you would actually find in your body. Does anybody want to guess what kind of cell that is? That's a neuron. So that's like a communicator in your body, or maybe it came from a rat. It probably came from a rat. But there's the link, so you can totally go look that thing up and find out, oh yeah, Riggs is so smart, because she totally knew it came from a rat. This thing, hopefully, this is not found in your body. That is some kind of single-celled organism. You are not a single-celled organism. Most of you are not single-celled organisms. You're multicellular, and so you have lots of different kinds of cells inside your own body. Other organisms are one-cell total, and that's the whole critter. So this is some kind of protozoan. I'm sure we could find out what kind it is, but yeah, you can go look that one up too, because there's the link right there. Good luck reading that thing. Let's go look at some more cell types, because it's really actually pretty cool. This is a fat cell. Look, here's its tiny little nucleus, and then this is its giant fat blob, and hopefully we have a reasonable number of these in our bodies. They're awesome for storing energy. That comes super handy. What kind of cells are these? These are cells inside your body. These are red blood cells and white blood cells. Look at how different they look. Very different structures, because the structure of these cells enables their unique functions. Another white blood cell. I think this is a giant macrophage. Doesn't it look like a jellyfish, but that's inside your body. And guess, that's not just one cell. Here, the blue guy is one cell, and it's reaching out with little hands in its... They aren't really hands, just so you know. But they're reaching out. Guess what it's going to do? It's going to yumptualize all of these cells. Those are not rat poops. Those are not purple rat poops. Those are purple bacterial cells. And this macrophage is like, dude, hook me up with some bacteria, because I like to yumptualize bacteria, and it keeps you healthy and well, as long as you make sure you're sleeping. That's awesome. So there, human cell and other critter cell. And we're going to look at, you know, why is that bacterial cell so tiny? More bacterial cells. What, really? Look at these. These are little spiral bacterial cells. And if you ever take microbiology, you'll get to learn all about the cool characteristics of that thing right there. Here is a yeast cell. This is actually a fungus, a single-celled fungus that is responsible for making pee poison that you drink and get drunk on, really? Yeah. So the next time you decide to go out and damage some brain cells by getting a little toasted on alcohol, just know that you are drinking yeast pee. And I'm just going to scare the crap out of you right now and tell you that this right here... Oh, my gosh, this is so cool. That is a microscopic view of somebody's cutting board. What? Yeah. And it's clean. That is not a dirty cutting board. That is not like the cutting board that lives in Wendy Riggs' house. That's like the cutting board that lives in my mom's house, and I guarantee you she cleans her cutting boards. Whoa, like let's just start counting all the different kinds of cells and things that we see on this cutting board. Oh, hopefully it makes you a little bit nervous. Clean your cutting boards. Lots of different kinds of cells. I think it's really interesting to think about like a total number of cells in our body. The estimates range from 10 trillion to like 100 trillion, and apparently these guys decided that, no, it's actually 37.2 trillion, which if you start thinking about big numbers, that's a huge number of cells inside your body. And then I also think it's interesting to think of how many different types of cells. So there's 37 trillion cells in your body, but then there's actually like 300 different kinds of cells in your body, and each cell has different structures that carry out different functions. And like what kind of cells are they? Dude, I was just looking at this list going, oh man, like this is a lot of different kinds of cells. Look at this one. I never knew this kind of cell existed. A Bowman's gland cell in your nose. And listen to this. It washes the olfactory epithelium. Do you know what that really is? The Bowman's gland cell is a snot maker. So you have cells in your body that do nothing but make snot, and you can call them Bowman's gland cells if you would like to. The list is huge. Yeah, go ahead and you can explore it like, whoa, look at all those different kinds of cells in our bodies. So when we talk about cells today, we're going to be looking at lots of different kinds of things. First of all, we're going to take a look at like what makes a cell a cell? How do we know if we actually are looking at a cell? And then we're going to look at, okay, what are all the different kinds of cells that we can explore? Knowing that basically we're going to be talking about cells for the rest of the semester because the cell is the fundamental unit of any living system. Shall we start? Let's talk about what makes something a cell. How do we know if we have a cell? Okay.