 Why are we studying glands while we're doing epithelial tissue? What is a gland? There is a gland. I have a picture of a gland. There's all different types, and we could totally go into the anatomy of the glands and figure out, name all the different kinds of structures. There's multi-lobed and assinar and I don't know. There's so many different kinds of glands. We don't have to go there. We're going to look at glands in general. It's a structure, it's not a tissue. It's an actual structure. Sometimes it's actually an organ, which means there's all sorts of different tissues interacting together to perform a common function. But we're talking about it with epithelial tissues because glands are lined with epithelium. So you can see that here. What does that look like? What kind of tissue does that look like? It looks like simple cuboidal epithelial tissue. What is this space right here? This is your aluminum. And then it's lined by epithelium. Where am I going to find my basement membrane? Right here along the edge, and keep a steady hand. Not so much. What are you going to expect to see out here in this space? Holy, connective, madness. Oh, you will understand in the next lecture that it really is connective tissue madness. And that's what's outside of a gland. We have two types of glands. There are exocrine glands and endocrine glands. But let's look at exocrine glands first. The difference. They both secrete substances. So the tissue, the epithelium lining the lumen in any gland is secreting substances into that lumen to be barfed out into the universe somewhere. But exocrine glands barf substance, stuff into the outside, the outside of your body. So if this is your skin, really, yeah, that's not happening. I can't write that tiny on top of that thing. But if that was your skin, and this was a gland that was barfing stuff onto the surface of your skin outside your body, it would be an exocrine gland. So this thing was barfing substance into your body, into your blood, that's actually where it has to go. Then it's going to be an endocrine gland. So let's do an endocrine, an endocrine gland barfs stuff into the blood. And what is it barf? What is an endocrine gland barf into the blood? Hormones. If the gland is producing sweat and the sweat is being secreted onto your skin, then sweat glands are exocrine glands. Exocrine glands often have ducts. This is an example of a duct. So the duct is like a neck where there's actually, you know, a space to go before you get dumped. Endocrine gland most of the time does not have a duct. The goal with the endocrine gland is to be close to the blood supply. Because that's actually the definition of a hormone. It's a chemical that is dumped into the blood that acts on a distant target. So your testes, not mine because I don't have any, your testes dump testosterone into your blood and that testosterone acts all over your body. It acts on your muscles all over making them bigger and bulky. Hmm, what else? Yeah, yeah, yeah. So I wanted to show you a visual of some endocrine glands. And look, here they are. So they're all over your body because they're endocrine in nature. They do not have ducts. This guy right here is the pineal gland. Tell me to write them down for you. I'm just stoked I know them all. This guy right here is the pituitary. Who's this cute little butterfly heart? That's your thyroid. Who's that cute little heart, heart? That's your thymus. Here is your adrenal. Here's the thymus that on top of your kidneys. Who's this bad boy? We're going to see this guy soon. This is the pancreas. Because it's digestive system, we're going to look at the pancreas. The pancreas is interesting and pituitary also because it has endocrine. Wait a second, pituitary is endocrine and neural tissue. The pancreas has endocrine and exocrine glandular tissue in it. I'm going to look at my cute little ovary. These guys all play a role in the endocrine system producing hormones that are dumped into the blood. So they don't need ducts. These are your testes. Oops, it's not a duct down there. It's your testy, fella. Good. So glands. You've just been glanded. Now let's go look at our lab and practice looking at some actual histology and then you'll have a little quiz set up for the next test.