 Basa fills are the least abundant of my fills and they are super, super unbelievably obvious if you find one, if you find one. The ultimate challenge is if you find one because they're so filled with giant, like bluish, really dark granules. You can't even see the nucleus, obviously they have one, but they look like a giant black blob because they have so many crazy granules. And I'm going to tell you what those granules are because it's related to their function. They are basically inflammation makers. Like they make inflammation happen. And inflammation is when you get an infection and you get red, hot, swollen, and painful. That's inflammation. These guys are filled with crazy granules that make that happen. And I'm going to tell you the name of two of the substances that they are found in the granules. One of them is heparin. And maybe heparin sounds familiar to you. It's an anticoagulant. I better write that down. Anticoagulant. Anticoagulants prevent clot formation. Heparin being produced during an inflammatory response is going to increase blood flow through an area which makes things red and swollen and hot and painful, but also can flush a system out if you've been infected by a bad guy. In addition to heparin, there's a pretty powerful inflammatory mediator produced called histamine. And hopefully histamine actually sounds familiar to you too. Histamine is an inflammatory agent also, but it's also a vasodilator. Vasodilation is also going to increase blood flow. So we're bringing in a lot of blood when we're having an inflammatory reaction. Antihistamines are produced because when you do have vasodilation and inflammatory stuff, you start snotting and tearing and itching, and you have all these terrible symptoms that arise as a response to that, but it's actually your body. There's a strategy behind why you would be reactive to something. Basophils. I couldn't find out how long they live, which I thought was kind of interesting. And rather than go find that and hunt that down, I decided I would show you a basophil instead. Which one of these cells is a basophil? Dude, please say that you're like, holy, like, wow, those really are super granularly. You can kind of see the nucleus in here, but yeah, there's no question that this is full of granules as opposed to this guy, which might be a neutrophil, probably is a neutrophil, but might be somebody else as well. Always when you're looking at your slides, you don't have to have a reference, who's most abundant? Those are going to be your neutrophils. Then look at those guys and go, okay, this is what a neutrophil looks like, and then compare everybody else to that, and that will help you make your decisions about what something looks like. But basophils are pretty obvious. All right, two left. We've got our monocytes and our lymphocytes left, and you'll notice that we are no longer in fill land. Who are my fills? All fills are filled with granules, and that's why we put them together this way. You could sort, if you were given all of them and asked to sort them, you could sort them based on their filliness. Okay, so now let's talk about the, it looks like monocytes are next.