 Small intestine, we have three parts of our small intestine. That's cool. And I'm just going to show you the distinguishing characteristics of them, the duodenum has an unbelievable number of glands, like crazy glands, like holy glands, like the glands everywhere in the submucosa. And what that means is that you're going to have to identify muscularis mucosii in order to be sure that you are actually in the submucosa looking at all those glands. The ilium in submucosa or lamina propria, has lots of lymphatic nodules, and they have a special name in the ilium. They're called Piers patches. I don't know why they're called something special there, but they're just the lymphatic nodules. But if you see a whole bunch of them, chances are you're in the ilium. Sometimes the large intestine also has lots of lymphatic nodules. I'm here. Well, we'll save the large intestine for the next one. So look for lots of lymphatic nodules. You're in the ilium. Look for crazy amounts of glands in the submucosa. You're in the duodenum. Now, the jejunum is a little bit process of elimination. If it's not those other two, then maybe it's the jejunum. The distinguishing characteristic here is in the mucosa. The villi in the jejunum are long and thin. And something that sometimes happens when the villi are so long and thin is that the slices will cut the villi in these shapes that almost look like you end up with lots of circles toward the lumen. And it almost looks like giraffe skin. And it's because you've caught all these villi at different weird angles. Instead of catching them all standing up nice and tall with how you'd want them to look, you caught them and chopped off their heads. That happens, too. Okay, so I have a couple of images to show you. Let's see. Does this look like a lot of villi? Dude, this is like a quintessential image of, yeah, those are long, skinny, thin, fine villi. And that's jejunum. Here's the other thing. Here's that thing that I was telling you. This is the lumen of this tube. And you can see those villi just got cut and it almost looks like giraffe skin. If you see something like that, it's significant. Here we have muscularis mucosi, which means that all of this is laminopropria, but this is submucosa deep to or whatever basal to that. And then we've got our big thick layers of smooth muscle there in muscularis externa. But this is jejunum and that is something that might help you decide that. I am going to show you the duodenal glands. I don't have a good slide of the pyre's patches and I'm just going to have to find one and show that to you. But check this out. I'm not even that close up in this slide. This is lumen. This looks epithelial. And then it looks like, yeah, that looks like the mucosa has shifted into submucosa. And let's go check this out because glands like right there and this looks messy. This tissue definitely looks like dense irregular connective tissue and look at all those glands embedded in that submucosa. So that's how you're going to tell your small intestine. I'm going to do the large intestine.