Connective Tissues: Types and Characteristics

and fiber bundle here's another collagen fiber bundle i'm sorry but i'm just not really seeing what you're seeing do you see the pink lines oh okay the thick be looking at the thick you're looking at the big pink line that's just kind of going everywhere yes only that that's collagen bundles all right gotcha okay and they're going to be the background color and when I say background it's going to almost seem like that it's background where other things pop in front of it. So in real life this is all three-dimensional, it's layers. We're just seeing it flat two-dimensional. So collagen is going to be the background, okay. The foreground we're going to see these thin pencil lines popping forward. Do y'all see those thin pencil lines? It almost looks like someone just took a pencil and drew all over it. Yes. Yeah. Okay, these thin pencil lines are going to be which one? It will be the elastic fibers. Those are the elastic fibers. So the elastic fibers you can see are kind of staining darker, like a purplish color, and they almost look like they're popping forward. So, collagen looks like it's filling the background information and elastic looks like it pops forward. So, on the test, I could ask you these questions. I could say, identify the fiber at the pointer tip. So, you know, imagine that there's a pointer tip, not just an arrow. Or it could be that I drew an arrow and I labeled the arrow one. Identify the fiber labeled one. I could say identify the cell labeled two. So on the test you're going to be asked to identify different structures. I could say identify this tissue. What would the tissue be? Areola. Areola. I can ask you a location and a function. You get those directly from the textbook. Okay. So that would be like a fill in the blank, like when you ask the location and we can just list around blood vessels or nerves. Yes. Yeah. And just remember that if you said around blood vessels, but you change that to be something else that means the same thing, it would probably count it wrong. And then I would have to go in and give you the credit. So don't stress too much about, you know. what your answer, how you write it. Just worry about getting your knowledge down. Okay. I don't want y'all to stress about, oh my God, I can't get the exact answer correct. I go in and I hand checked everything. That's why it takes a while to grade them. Okay. So I'm going to continue on with my analogies. I'm going to give my husband credit for this one because I cannot think of anything that looks like areola that's food. I always think it kind of looks like a spider web to me, but my husband told me he sees spaghetti, so I went with that. I don't really see it, but it may help you, it may not, but basically the spaghetti would be the fibers and then all the little chunks of whatever's in there would be the cells. So thanks for laughing at that. I'll tell my husband that someone agreed with this. I definitely agree. No, but the little purple whatever in there in the spaghetti looks like the... The picture. The, what you call, the nucleus? Wait, the macrophage? The fibroblast? Yeah, the fibroblast. Yeah, the cells? Okay. Okay. So, do y'all see how there's a pointer in the areolar tissue right here? This is a pointer tip? Yes. Okay. Yes. pointer tip is pointing to a cell in the chat put a for fibroblast or b for macrophage in the chat put a for fibro or b for macro great job y'all are doing great okay so people put a for fibro really good okay so that's our first loose connective tissue. Our next loose connective tissue is adipose. Adipose connective tissue is what? What do y'all commonly call this? Marshmallows. It is marshmallows, but what is it? It's bone. I say bone. It's fat. Okay, now while adipose tissue is usually my class's favorite because it's pretty easy to recognize, the questions asked about it are where the students often get confused. So this tissue is known as adipose tissue. Remember that tissues are made up of cells. The cells are called adipocytes. What does site tell us? You got to maintain. And then adipose tells you fat. So what are the sites maintaining in your body? Fat. You got it. Okay. So. Adipocytes are basically these big circular cells and they are filled with a big old fat droplet. That fat droplet is so big it pushes everything to the side so all you really see is a white circle with maybe a nucleus stuck to the side. Inside is the fat drop. So the white that you see is the fat drop. So on this picture, this whole cell is one adipocyte. Okay, here's a nucleus. Here's another adipocyte. Here's a third adipocyte. So each of these cells are a single adipocyte. What is this white stuff that fills the middle what is this right here fat deposit that is your fat so some people call it a lipid droplet some people call it a fat droplet some people go fancy and write triglyceride any of them are fine okay so let me tell you what the questions are like if i said identify this tissue what would the tissue name be apples loose tissue. Oh, loose tissue. Nope, nope. Go. You were right the first time. You always want to go specific. Oh, adipose. Remember, loose is a group that defines characteristics. It defines that we see a lot of cells. Okay, if I said identify, here's my pointer tip right here, identify the cell at the pointer tip. I did both sides. What is stored in the cell at the pointer tip? What is stored in the cell at the pointer tip? Fat drops. Perfect. So when we talk about this tissue, the name of the tissue is adipose. The cells are adipose sites. And the storage is a fat drop, lipid drop, however you want to call it. So if we ask the function, the function is just, I guess, storage. It stores fat around organs. That's a function. It actually has quite a few different functions, but that's a function of it. All right. So let's go to our typical analogies. You all see the similarity? Yes. Okay. So when I see adipose, I see marshmallows. So that's just my little analogy. Now, when you look at adipose tissue, so we're looking at this picture or we look at these pictures, the actual tissue itself is pretty white. So there's actually two types of adipose tissue in the body. What we're looking at in these pictures and in that picture are called white fat. But there is another type of fat in the body called brown fat, also known as batty tissue, brown adipose tissue. Brown fat is only going to be found in newborns. So brown adipose tissue is found in newborns. It has more mitochondria. and more blood vessels than white fat. You say more mitochondria? And more blood vessels than white fat. Now as the newborn develops, brown fat converts into white fat. And you do have a little bit of brown fat in the body as adults, but every person's different. So you may have 0.05% and someone else may have 2% of brown fat. So it's not very common in adults. But the reason newborns have brown adipose tissue or brown fat is the newborn needs to keep their temperature higher. They need it to thermoregulate. So brown fat is used for thermoregulation more than regular white fat. So brown fat is used for thermoregulation. You are not going to have to identify brown fat. You only have to recognize regular white fat. What does more BV mean? What is what? Say that one more time. More BV. Blood vessels. Oh, blood vessels. Thank you. Sorry. Thank you. So I just want you to think. cellular cellular respiration is how we make most of your body's ATP. ATP can only be made if we have nutrients specifically glucose that's the easiest way to make it brought to the mitochondria and oxygen. So the more blood vessels we have the more sugar and the more oxygen with the sugar and the oxygen the mitochondria can make more ATP. that ATP is used for thermoregulation, so keeping babies warm. Now this picture, the ones that are book ending on either side, this is brown fat. It looks totally different than white fat. Yeah, it looks purple. But remember that's a stain, but I know it doesn't quite look the same. The fat drops are much smaller. They're what you call bi-trioculated, meaning that there's lots of little fat drops instead of one big one. So you don't have to recognize it. I just wanted y'all to see the difference between them. Should we remember that big word or no? I just want y'all to see the difference and understand why there is brown fat. Okay. So would one of the questions be like, what is a function of adipose tissue? And then we will have to write out one of the functions. So functions are primarily physiology tests, whereas it's going to be like a true false, right? I'm sorry, say that again. And that's going to be more of a true false, true, false, multiple choice matching. So the physiology tests are like what you would. be used to taking for a regular test like scantron usually except for we're online so there's no scantrons so when you think functions think physiology when you think anatomy think mostly practical okay which would be more identifying yeah practical is more anatomy so you more identify i have that all written in the announcement I'm so just a little confused. I'm sorry. Okay, so if you go to the announcement that I posted for test one, it talks about the differences between the practical and the physiology, and it's explained in the syllabus schedule and the addendum. And she tells us what's on it, how many questions, multiple choice, how many minutes, each part. She tells us the practical, what's on it, and the anatomy that you have to label. She break it down. Yes, I saw that. I just needed a little bit more clarification. Yeah, and there's also a study guide that will help guide you. It's just a guide. I don't, I personally don't really believe in study guides, so it's just to guide you. Okay, so we've done areolar and we've done adipose. Our final loose tissue is reticular. Now, when you look at reticular, What you're going to see are lots of cells. So remember, loose means we see tons of cells. It doesn't mean fibers aren't present, it just means that we see a lot of cells. Based on the name reticular tissue, what fiber do you think this has? Fiber. It does have fibers, but which one? Reticular. Yeah, okay. So, reticular tissue has reticular fibers. If you remember, I said that reticular fibers are short and wavy. These little cracks in here, those are all reticular fibers. So, I kind of think they just look like little cracks in glass. All of these that I'm tracing, those are all the reticular fibers. Okay, all of the circles behind them are all of the cells. And you can see that there are tons and tons of cells. That looks like pink peanut brittle. Oh, that's a good one. That's a new one. Pink peanut brittle. That works. Okay, now with reticular tissue. Since it has reticular fibers and their job is kind of a supporting fiber, we're going to find reticular tissue in hollow organs that are small. So lymph nodes, you're going to find it in the spleen, parts of the liver. The liver is not small, but you don't find it everywhere. So it's a supporting tissue. Now, one of the most important. Sorry, Veronica, you had something? No, I said spleen, liver. And what else did you say again? Lymph nodes. Okay. Now, since reticular is found in a lot of places supporting, one of the most important places that we find it is in your red bone marrow. So, it is found lining the area of red bone marrow. It is very important in blood. production. So it's kind of a filtering support tissue for red bone marrow. It's a supportive what? It's a supportive filtering tissue and it's located with red bone marrow. So really important with your bone marrow. Red bone marrow. Okay. Now we have seen this tissue for those that are also in my lecture. We've kind of gone over some of my analogies before. So I like all food analogies, but not everything has food all the time. So this one, cherry blossoms. And then I also kind of think clusters of fruit. That's just another description that I kind of think of. And now I'm not sure who said it, but who said the peanut brittle? Stephanie, if it's Morris. I see that too. So maybe I'll add that to my collection next time I teach. I think the cherry blossoms are like spot on because the branches look like the fibers and then the blossoms look like the sows. So. Lots of different things you may see. Kind of depends on your imagination. So we have covered three loose tissues. We've covered areolar, adipose, and reticular. Now, I'm going to go through just a few questions. What's the function, ma'am? Sorry. Where do you get the function? In the red bone marrow. No, but where do you find the functions? It's on page 127. Everything's in your textbook. Because of time, I'm going over 11 tissues today. I don't have time to give you all everything, so you go straight to your textbook. I'm only covering things that I'm highlighting that I think are super important. Sorry. No, it's fine. There's no way I can go over everything in a three-hour period. Okay, so the next... thing is going to be just a few questions just throw your answers in the chat and then we'll move on to dense so here's your first question tyrone's getting fancy and answering with the full word okay Now we're going to go to the next question. Everybody that I've seen has put C, which is reticular, and that is correct. Here's the next question. Okay, very good. Everybody was putting B, areolar. Areolar is the scotch tape of the body, not the duct tape, because it's not that strong, the scotch tape. Always go with the best answer that you see. I have to take my watch off because I get buzzed every time y'all answer a question. It's connected to my Apple Watch Teams. Okay, good job. So while loose is a correct answer, it's not the best answer. The best answer is going to be reticular because reticular is a specific tissue. So you will rarely, if... ever with me be answering the term loose, dense, cartilage, liquid. You will always be doing a very specific name of a tissue. Okay, so we've done loose. Loose is lots of visible cells, loosely intertwined fibers. So dense is going to be basically the opposite. Dense is going to be tightly packed fibers. They're so tightly packed that the cells are not as visible. Dense is going to be tightly packed fibers, and they're so tightly packed that the cells are not as visible. Tightly packed fibers that are so packed that the cells are not as visible. Does that mean that there are not cells? present? No. Do we see them as easily though? No. You got it. Good answers. Okay, so we have three denses. Dense regular, dense irregular, and elastic. With the word elastic, be really careful. We have elastic fibers, elastic connective tissue, and elastic cartilage. So you just want to be really careful when you use that term elastic and make sure that you put an ending on it. Because you don't want to confuse elastic fiber with elastic connective tissue with elastic cartilage. So you just have to be careful with naming that. All three denses are going to be used for strength. So which fiber are we going to have tons of? Corn. collagen good job y'all collagen good job so who is collagen's buddy who does collagen like to hang out with elasticity elastic now just because it hangs out with elastic does not mean we can always see the elastic okay collagen is a much more forward seeing fiber we see that one more easily so we're going to go over the first one which is dense regular okay dense regular is going to be collagen fibers running in a regular pattern so they're all running the same direction so collagen fibers running in a regular pattern that pattern can be up and down left to right it can be at an angle but no matter what what we're seeing is that they're running in one direction. So in this particular picture, both of them are running up and down. I could actually make this picture and it can run left to right, but the similarity is that they're all running in one direction. Now, since we have so many fibers, what type of cell makes all these fibers? collagen fiber bundles yeah so the cell would be uh was it chelsea that just said that or brianna brianna brianna so brianna just said fibroblast so remember if i'm asking for the word cell The word cell is going to be a blast, a site, a clast. So fiber blasts produce the fibers. So what we're seeing in here is we're seeing not as many cells, but we're seeing lots of smushed fiber blasts that are kind of looking like smushed pancakes because they're being smushed between all the fibers that are tightly bound together. So we still have a lot of cells, but the cells are not quite as visible as they were in loose. Now, since these fibers run in one direction, are bidirectional, what happens is that they're really strong in the direction they run. So in this picture, they are really strong going up and down. But the minute there is... pressure from the left or the right they're not as strong anymore and they can easily tear so i want y'all to think about the acl have y'all heard of the acl yes okay it's a very common ligament that is a super common injury so the acl is a ligament in your knee you also have a pcl and mcl so you may have heard those too. This is a very common injury in football, soccer, and that's because this ligament runs up and down. So when your knee gets hit from the side, the ligament's not as strong from the side, so it causes tears. So we find dense regular in your tendons and your ligaments. Do y'all know the difference between tendons and ligaments? One connects bones to bones, one connects bones to muscles. Which one do tendons do? Bone. Bone to muscle. Okay. Bone to muscle. And then ligaments are going to do bone to bone. So tendons and ligaments, they're the same structure. They're both made out of dense regular, but tendons connect bones to muscles. Ligaments connect bones to bones. So have y'all heard of the Achilles tendon, that huge tendon in the back of your leg going from your calf to your ankle? Yes. That tendon connects your heel bone to your calf muscle. So bone to muscle, heel bone to your calf muscle. Wait, say that again. Achilles? Oh, that was just an example. The Achilles tendon connects your calf to your heel bone. So calf muscle to heel bone, whereas ligaments connect bone to bone. They're made out of the same thing. They're just different locations. So let's do another analogy. This is dense, dense regular. And what are these candies? Twizzlers. Collagen. Wow. So Twizzlers, which are the collagen. And just pretend that all these little like shadows between all these shadows are going to be the cells. What are those cells called? Macrophage and Iberblast. They're only going to be fibroblasts on this particular picture. So this is just an analogy, y'all. This is not science. This is just ways to kind of get your memory thinking to separate all of these. So in this picture that we're seeing right here, this picture, remember that this is collagen fibers all running in one direction. bidirectional up and down in this picture. And then these are what cells? Fibroblasts. You got it. Okay. So dense regular is when the fiber's running a very consistent pattern. What do you think dense irregular is going to be? Do you think they're going to have one pattern? No, it might have. No, they look more chaotic. Might have different points. OK, so I heard chaotic. I heard different. And what did you just say Jeremy messy? Messy. All of those are great descriptions. Quick question. Yes. For the dense regular, is it always going to be dense collagen fibers? Yes, it's going to be collagen. There is elastic present, but we rarely ever see it. Okay, thank you. So basically, you were seeing pink fibers. Now, if we were actually in lab, and I don't know why I don't have a picture of this, but if we were actually in lab. and we were using slides, there are a few slides that I love that don't have any stain to them. And the reason that's good is because you only see the structures, you don't memorize color. And if you can let me see if I can find one online, just because it's really important to start seeing things. oh see all these are stained we have some really nice one in the book is is there one in the book that's not stained it's just kind of like a brownish yeah it's actually clear and i i thought i thought i may have had one i probably have one somewhere in one of my files it's just finding that file won't be that easy i'm just gonna look super quickly because we don't have time for me to really look for a long time If I had this, like, if it was my choice, we would not learn stains at all, but that's not my choice. So most of our stuff is stained. What's wrong? At one point, I did have this picture somewhere, and I don't know where it is. Okay, well, it's not on my immediate pictures for class. But when they're not stained. It's you just see the direction and the shape of the fibers. You're not seeing any pink. Okay. Oh, I'm not finding anything. If I find it, I'll send it to y'all via email. I don't want to waste too much of y'all's time me finding what I like to show y'all. Okay. So our next one is dense irregular and it's just a mess. We still see collagen but the collagen is no longer going in one direction. The collagen is going, it's not going up and down or side to side anymore. It's going in all different directions. So it's kind of like swirly. So each of these arrows I'm drawing are collagen fibers going in different directions. And they're bundles, they're not single fibers. Now the reason this is so important is because when collagen goes in all different directions, no matter which way it is pulled, it is strong. With dense regular, it's only strong in the direction it runs. With dense irregular, it's strong in every single direction. So your biggest portion of your skin is your dermis. So both of these pictures here are showing the dermis. So this whole picture is the dermis and all of this is the dermis. Your dermis is the... The... bulk of your skin and if you think about your skin you move it constantly it goes around your legs your arms your torso and you move it in all different directions all the time it's twisting and it doesn't tear that easily because the collagen's in all different directions so it's very strong it's one of these stronger tissues in your body the whites of your eye is known as the sclera That is also made out of dense irregular. And then the periosteum and the perichondrium. What does the word peri tell you? Outside. Close. Very close, Veronica. Surrounding. Running around. Yeah. It is on the outside, so it goes around something on the outside. So periosteum is going to be going around what? Okay. What does ostium sound like? Around bone. And what does perichondrium tell us? Cartilage. So basically around your bone and around your cartilage, you may have a layer of dense irregular tissue surrounding it. You may, not all of it does, but most of it does. So around bone and around cartilage, you may have dense irregular surrounding it because it provides strength and structure. I'm sorry, periosteum is the outside of bone? It's a layer of tissue on the outside. And perichondrium is the same, but it's on cartilage. So when you look at dense irregular, the fibers don't run in one direction. They run all over the place. And I think it looks like tenderized meat. Mm-hmm. If you don't see it, it's perfectly fine. This is just what I see when I look at it. Yeah, but it looks more like the one covered with a lot of fat, though. Yeah, that fatty area is kind of like the ground substance. Mm-hmm. So this is just what I see, y'all. But it's not close. Yeah. I also see in my head cotton candy just because it's very airy and the fibers of the... sugar go in different directions. Okay, so we've done dense regular, and we've done dense irregular. The last dense is elastic connective tissue. So this is elastic connective tissue. Lasagna. Lasagna, which I have a picture of in a second. Okay, when y'all look at elastic, you see two major colors. Do y'all see kind of a background pink? A little bit. A little bit? Okay. What fiber stains pink? Glitch. Areola. Collagen? Well, areal is a tissue. Collagen, collagen. Oh, collagen, I'm sorry. Collagen. Okay. And then what fiber are long and skinny and staying dark and pop forward? Elastic. Elastic. So elastic connective tissue is going to be both elastic and collagen bundled together. But the reason we see the elastic fibers is because there's so much more of it. Now, we find elastic connective tissue in areas that need a lot of stretching but recoiling. So we find this in your major blood vessels. So like your aorta is your largest blood vessel, and we need that blood vessel to get bigger and then get smaller as blood's pumping through it. So we find elastic connective tissue in areas that need to stretch and recoil. Stretch and recoil. Now in this there are two major fibers we see. We see that kind of purple skinnier fiber that pops forward. What is the purple skinnier fiber that pops forward? Elastic. Elastic. Elastic fibers. And great and then that background is going to be that pink and because Anything that stretches and recoils, we need to have it be strong so it doesn't tear. That background kind of pink color is going to be which fiber? Polymer. You got it. So I personally see both. Oh, I forgot to tell you all this. Most of the pictures I'm using, most, not all, are from our lab. So they're either I've taken them or students have taken them. Not all of them are, but most of them are. that's just so y'all can kind of see the quality that you will see on the test. So just be reassured that we use good pictures on the test. I don't use some of the crappy stuff. So when I look at elastic, I took two different stains because one looks like lasagna to me and one looks like turkey bacon. So this is the one that looks like lasagna to me, one that's darker in color. If you don't see it, it's not a big deal. Okay, so I see lasagna when it's really stained heavily. Oh, ramen's good. Ramen noodles is really good. Jocimer said ramen. Yeah, before you take it apart. Yeah. And then this one is the lighter stained one, and I see turkey bacon. Exactly. If you don't see turkey bacon, don't worry about it. I see ham, too. Like when you want a ham sandwich. So remember that these are just kind of silly things that I use to help with, you know, association. So these are just different ways to help you all kind of remember stuff. OK, so we've done three denses. We've done dense, regular, dense, irregular and elastic connective tissue. We are going to go through just a few questions. Just write that answer in the chat and then we'll move on. OK, so here's your first question. Okay, so the a torn ACL is a torn ligament. So think about what ligaments and tendons are made out of. Okay, so everyone is putting B, which is great. And even someone that put A said, oops, B, way to go. Okay, so an ACL, anterior cruciate ligament. Okay. Ligament tells us it's dense regular. Okay, and most people, I'm gonna give just another second to put in. Okay, so most people or everyone I think put D. So D is tendons and ligaments. Which one, which dense tissue would we find in the dermis of the skin, the bulk of your skin is which dense tissue? Tense irregular. Good job. What is padding that protects our organs? Which tissue is the padding that protects our organs? Pusheen. Adipose. Good job, good job Yuri. And then what tissue do we know we find supporting those small hollow structures such as the spleen and lymph? It looks like cherry blossoms are clusters of fruit. Reticular. Reticular. Good job. Okay. Okay. We're going to take just a short break, like a two-minute break. Just go stretch, run to the bathroom if you need to, because we still have five more tissues to go. So just take a real short break, and then we'll start back up in about two minutes. Thank Okay, it's been two minutes. Are we back? we're ready to go okay so we've done loose we've done dense now we're going to hop into cartilage cartilage is a very unique tissue because it has certain things we haven't seen yet okay it also is that tissue that's kind of the exception to all of the connective tissue rules it is avascular what does that mean It doesn't have a lysopon. It doesn't have blood. Yeah. Okay. So it's avascular. It lacks nerves. And we can find it lining structures. Not all cartilage does that, but some cartilage lines structures. So it's kind of the rebel of your connective tissue family. Now, cartilage is going to have some very unique. characteristics that helps us identify it. The first characteristic is that it's always going to have a ground substance. Now all tissues have this, all connective tissues have it, but cartilages you can see really well. And in this particular picture I have, the ground substance is all the purple that surround these little white holes. The ground substance is made out of chondroitin. sulfate. So what does chondro tell you? Cartilage. Yep. It means cartilage. So if you see that word chondro, it's referencing cartilage. Now the chondroitin sulfate may or may not have fibers in it. In this particular picture I have up here, there are no fibers, but there can be, just not the one that I have up here. Now, Now, something that's unique to cartilage and we'll also see it in bone is, do y'all see all these little white holes? These little white holes are called lacunae. Lacunae are just kind of like little divots that have cells that sit in them. These are the cells that maintain cartilage. What cell maintains cartilage? Lacunae. Well, that's what they sit in, but what cell maintains it? Chondrocytes. Chondrocytes. We know cytes means maintain, and we know chondro means cartilage. Okay, and you can see the lacunae over here too. Now, a lot of these lacunae on this last picture are... empty and that just means the chondrocytes died so if you don't see a cell in a lacunae it's fine it just means the cell died okay now the last thing is that cartilage can have a perichondrium and we just kind of went over this what's the word peri mean surrounding what does chondro mean okay So two of the three cartilages we're going to learn will have a perichondrium. The perichondrium is made out of dense irregular, which is just one of the last tissues we went over. Not all cartilage has a perichondrium. Two of them do. The two cartilages with the perichondrium are hyaline cartilage and elastic cartilage. Now, why is a perichondrium good? It is good because it contains blood vessels. It is protection too. So whoever just said protection, that's another good answer. So perichondriams contain blood vessels. What do cartilage tissues lack? Blood. Blood supply. Yeah. Blood vessels. Yeah. So if cartilage is damaged. they don't have blood vessels in it to heal it. So all of the nutrients and cells, they have to diffuse from other blood vessels. If the perichondrium is present, that means that there are blood vessels that are right next to that cartilage. So the chances of them healing is going to be faster and better. So these are just general characteristics of all cartilage. they're gonna have a ground substance they're gonna have lacunae which are just these little pits that hold cells and they can have a perichondrium they can now what is this tissue right here y'all that's above the perichondrium adipose say that with confidence yeah so The one thing that we are missing by not being in the lab is that at the end of classes, I usually pick certain tissues, actually not tissues, certain slides that will have about eight tissues on it. And then I'll go through them and test y'all. And it's great because regardless of where it's from in the body, you know these tissues and you're able to go through them. Now, we have three cartilages in the body. Hyalin, elastic, and fibrocartilage. Hyalin and elastic are the only ones with a perichondrium. Fibrocartilage does not have a perichondrium. okay do any of these have blood vessels though do any of those cartilages have yes no which one i heard no and i heard yes what is about cartilage is considered oh okay i was thinking about the perichondrium yep and the perichondrium does have those blood vessels but it's not cartilage it just surrounds Right. So we are going to go over Hyland first. And anytime you see a pointer in a picture, that means that it was taken in our lab. So these are very good cell slides. This is Hyland cartilage. Hyland cartilage is the most abundant cartilage in your body. So you have the most of it. It's also the weakest. So go ahead and touch your finger to the tip of your nose and wiggle your nose. That is hyaline cartilage. Pretty flexible. Do y'all know how babies are super flexible? Like they can literally like turn into a pretzel. That's because their bones are made up of hyaline cartilage. They haven't fully ossified. So they haven't fully hardened into bone. And yeah, that explains why they can be a gymnast at a young age. And then if you the ends of all bones, all long bones are covered with highland cartilage and it's called articular cartilage. So the ends of all long bones are covered with. thin layer of cartilage called articular cartilage. It is made out of hyland, but it's named for its location. So articular cartilage is hyland cartilage that lines the ends of bones. Articular cartilage is hyland cartilage that lines the ends of bones. When we look at the cartilage, what are each of these little pits called? Lacunae? You got it. So if it's just an A that's singular, if you put an E on it, that's plural. I'm really not picky, but I will give you a warning that some teachers are OK now in a lot of the lacunae were actually seeing cells. What are those cells? Fibro... Okay, well what tissue are we talking about? Cartilage. So what would the beginning be? Chondro... And then what cells are going to maintain the cartilage? Chondrocytes. Okay, so all these little nuclei that we see in the lacuna, those are chondrocytes. Now... Does cartilage have fibroblasts? Yes, but we're not going to see it. Wait, say that again, Dr. R. I said that cartilage can have a fibroblast, but we're not going to physically see it. We're only going to see chondrocytes. Okay. Now, all of the stuff between the lacunae, so in this particular picture, all of this purple. and in this particular picture kind of this pinkish color that is filling everything between the cells what is that going to be the matrix okay and the matrix can have both fibers and ground substance ground substance yeah specifically this ground substance is known as chondroitin Sulfate. So, doesn't matter what picture we're looking at, all of this stuff that surrounds the lacunae is all ground substance, and it's known as chondroitin sulfate. So, do all cells have lacunae? All cartilage has lacunae, and the cells sit in the lacunae. the cells sit in there so the lacunae are the cells kind of like living space okay all catalyses have lacunae now is the ground substance going to be made of the chondroitin sulfates and other areas or solely in the cartilage a chondroitin sulfate is solely for cartilage but there will be other stuff in it So it will also have dermatinsulfate, hyaluronic acid, but we're only focusing on chondroitin sulfate. Okay, thank you. Now, for this particular cartilage we're looking at, it's hyaline. You're not seeing fibers in the ground substance. So hyaline cartilage, you cannot physically see fibers. Fibers are not visible. So for hyaline cartilage, fibers are not visible. Now I'm just going to change pictures and show you two more pictures of hyaline. So Dr. R, what is the pink on top of the picture to the right? This one right here that my mouse is going over? That is your perichondrium. So it sits above? Yep. It actually surrounds it. So it's on both sides. So it would be down here if I had the bottom of this picture too. Oh, okay. Okay. And so the highland part is in between there? Yeah. So this is the highland. So let me go back. Nope. Those pictures. This one's a little bit better. Let me erase all this and show you. This one kind of shows you everything. From here to here is your hyaline cartilage. And then this area is going to be your perichondrium. Okay, now I see it. It does look different. I see it now. It just depends on how much I blew up a picture. So this is hyaline cartilage. Again, it doesn't really matter the stain. You're not seeing fibers running in the ground substance. Now, fibers are there, there's just not a lot of them, so they're not very visible. So that's why we say you cannot see them. What are all of these circles called, these little pits? Lacunae. Lacunae. What sits, what is the cell in the pit? Chondrocytes. Chondrocytes. Okay. Now, the cartilages are just something that I'm going to tell you all, spend time on. Okay? Spend time looking, Google, see tons of pictures. So this is hyaline cartilage. Our next one. is elastic cartilage. Both of these pictures came from our lab. What I want you to notice is in the ground substance, you're seeing individual fibers. So all of those kind of lines that you are seeing, those are all fibers. Based on the name elastic cartilage, what type of fiber do you think you're seeing? Elastic. Elastic fibers. Whoa, I don't know. I'm learning my new computer still. I just learned that I can then blow things up for y'all. Okay, so elastic cartilage has elastic fibers. It's still really flexible, but it's much stronger. So everyone take their hand. and grab the outside of your ear, the upper part of your ear. Okay. You see how you can still kind of bend it and fold it? So it's still flexible, but it's much stronger than hyaline cartilage. And that's because it has those elastic fibers in it. So your outer part of your upper ear is known as the auricle. Some people call it the pinna. Either name is fine. that is where we find elastic cartilage oracle or pinna does elastic cartilage have a perichondrium yes or no no yes yes elastic yes elastic cartilage yes to a perichondrium Okay, now I'm going to show you two more pictures that came from our lab. These you can see the fibers a little bit better. So can you also kind of see these it almost looks like fray from jeans between the pits. All of those are fibers. Right here is a fiber. You can see the fibers. Whoops. you can see the fibers really well in there it looks like a cluster of frog eggs oh that's a good one so we're gonna say frog eggs that looks really that's a really good one um do y'all still see these little pits right here here here what are those pits called lacuna lacunae and what is found inside of them what cell do we find Okay, so I really like the frog egg comparison because my whole master's degree is on amphibians and reptiles. But when I look at this particular picture, I see oysters on the half shell. Yes, indeed. 100%. So again, y'all. For the cartilages, it's one of those things I just emphasize, spend a little extra time looking at pictures. Okay, so we've done hyaline cartilage, which is the weakest and most abundant. Elastic cartilage is stronger, but it's still very flexible. Our next cartilage is fibrocartilage. Based on the name. What does it have a lot in it? Fibers. Fibers. This is your strongest cartilage. Strongest. Which fiber is in it? What's your strongest fiber? Collagen. Fiber cartilage is full and full of collagen fibers. Just tons of collagen fibers. That's it. you There's so many collagen fibers, it's sometimes hard to see the lacunae. So, there's just so many of them. Now, these two pictures come from our lab. This is what our older specimen looked like, and this is what our newer slides look like. You can still see the collagen. In this particular picture, it's blue, it's not pink. What are these pits called that we can barely see because there's so many fibers? Lecune. And then what are these cells that are staining a pink that we can see really well? Chondrocytes. Chondrocytes. You got it. Okay. So remember how I said collagen almost always stains pink? Mm-hmm. I said almost always. This is just an example of when it stains blue. Now, can they stain fibrocartilage pink? Yes. Here's a picture of it. We personally don't have any pink slides. All of our slides are blue. So I just wanted to show you that it can be pink. Now, this one came from the web. This is not a picture we took. But what I want to... emphasizes that it has so many fibers, it is super strong, and it still allows some flexibility. We find fibrocartilage in areas that take just a lot of beating from you. What joints do you know that you just abuse by everyday living? Your knees and your back. All the limbs. Knees, yeah, definitely. And I'm going to say vertebrae, which is referencing your back. We find fibrocartilage in areas that need to absorb a lot of shock and take a lot of tension away from all of the movement. So we find the fibrocartilage in meniscus of your knee, which is just a disc of cartilage in your knee. And we find it in your... intervertebral disc. Intervertebral disc. So you hear about people talk about a herniated disc or a slipped disc. It's fibrocartilage. We also find it, and this is important for everybody because everyone has this, in the pubic symphysis. That's a piece of cartilage between your hip bones. So every time you walk, it's not just your knees. Your hips are moving and they absorb a lot of the shock and friction. Isn't your sacrum lined with some type of cartilage? I'm sorry, say that again. Your sacrum. Is that right? Oh, your sacrum. So between your sacrum and the lumbar vertebrae, right? above it, you're going to have a fibrocartilage disc. Okay, you do. Okay. Yeah. Yeah. It's not going to be, it's going to be at the top of your sacrum and you're going to learn those parts soon. It's called the sacral promontory. Thank you. Now, does fibrocartilage have a perichondrium? No. No. Super important because that is why you often hear about surgeries. So if you get a torn meniscus, which is a very common injury to the knee, if it's not a bad tear, they'll let it go. But if it's a bad tear, the only way to fix it is surgery. And that's because these just don't heal that quickly because there's no blood supply near them. And they're so dense, it's hard for things to diffuse through them. So again, with your cartilages, hyaline, elastic, and fibrocartilage. Just Google these, look at tons of pictures. That's going to be the best way to learn these. So fibrocartilage has no blood supply, right? None of the cartilages do. Okay. But fiber doesn't have that perichondrium. So there's like no blood supply near it. So it takes it even longer to heal. To heal. Okay. Okay, so I'm just going to throw up a few questions. Same thing, just throw those answers into the chat room. OK, I got only about 10 of y'all have answered few more answer. OK, so everyone's putting C. That's correct. Here's the next one. OK, everyone's putting C for this one also. OK, the next tissue we're going to cover is going to be bone and then blood. I'm going to go to blood first just because it's a lot faster to go through. And that way I know exactly how much time I have left for bone. So I'm going to skip quite a few for a second and go straight to blood. There we go. OK, so we're going to do blood first and then I'm going to go back to bone. When we think about blood, it is our only connective tissue that we are learning that is going to be what consistency? Liquid. Liquid. Got it. So when we think about loose, dense, and cartilage, they're all what we consider like gel-like. I think of silly putty or gum. That's like gel-like. It's solid, but it's flexible. When you think of bone, it's hard and solid. but when you think of blood, blood has a liquid portion to it. So blood is actually made out of a group of things. It is made out of cells because it is a connective tissue and it's made out of the matrix and the matrix has fibers and the ground substance. The fibers are very specialized fibers. We did not actually talk about these, so don't stress about them. You'll learn that in A&P too. But the fibers are very specialized fibers for clotting, so they're not one that we specifically talked about. The ground substance is going to be your plasma. And then the cells, we're going to have three cells we talk about. Erythrocytes, leukocytes, and thrombocytes. so the first cell is a urethrocyte do you think you're going to get credit on the test if you put red blood cell probably not probably not you need to put your erythrocyte even if you misspell it it's a quarter of a point off so 0.25 if you write red blood cells it's wrong so go ahead and misspell it and just get a quarter of a point off instead of getting it wrong Erythrocytes are the most common blood cell, but they're not even real cells because they are enucleated. I cannot spell today. Let me start that over. Enucleated. Okay. What that means is that they are without a nucleus. So red blood cells, urethrocytes, are not even real cells because they lack a nucleus. They only have about a three-month lifespan and does anyone know their function? Transport oxygen to the rest of the body. Perfect, okay. So red blood cells are the most abundant, they lack a nucleus, and they transport oxygen. They basically look like the pinkish red dots that you see over and over again. Since they're the most abundant, that's what you see the most of. The next cell is going to be a platelet, also known as a thrombocyte. Platelets are not even cells, they're pieces of cells. So they're like torn up cells. If you take a piece of paper and tear it in pieces, that's like a platelet. You do not need to recognize platelets on pictures you just need to know the function for platelets you only need to know the function you do not need to recognize them in pictures what's the function blood clotting because we only look at magnification of 400. And this right here at 650 is a platelet. You don't know if it's dirt on the slide or if it's actually a platelet. So I just require y'all to know the function, not to recognize them. And our last cell, which is a true cell, is a leukocyte. Leucocytes can be spelled two ways. So if you spell it L-E-U-C, that is fine. So it can be a K-R-C. What do y'all notice about a leukocyte? There's two big things about it that are very different. It's larger and it actually contains stuff in it. Okay. The first thing is it is larger. They are so much bigger in size. And then what is it that it contains inside of it? What does a red blood cell not have? A nucleus. And all leukocytes will contain a nucleus. Now, there are lots of different types of leukocytes. All you need to know is leukocyte. That's A and P2 that you learn the different types of red blood cells. of white blood cells. Now remember that this picture we're looking at is much larger than what we normally see. So I'm going to go to pictures from our microscopes to show you the difference. Now on this particular pointer right here in The chat area, I want you to put A for erythrocyte or B for leukocyte. I'm just writing RBC and WBC right now for shorthand. So A is erythrocyte, B is leukocyte. So what is the pointer on in that picture? A is erythro, B is leuko. Y'all are really rocking out today. I have really good feelings about this test. Okay, everyone's putting leukocyte. That's correct. Can y'all see that they're much bigger in size? That's a leukocyte. Leukocyte. Leukocyte. Here's one on the edge. There's a few things that tell you right off that it's a leukocyte. It's larger. You can see a nucleus inside of it. And there's not that many of them. What are all of these that we see everywhere that are just basically the whole picture? Arithrocytes. You got it. And then what is this white fill in the spot, fill in the between the... Plasma. Those are plasma. Plasma. Perfect. Okay. Now, I've kind of stretched far with this analogy, y'all. I couldn't really get one in my head, so I went for M&Ms and Smarties. Oh, my goodness. I had stressed a little bit, but it may help you. It did. You are so innovative. That's how I've learned. Science was always a struggle for me. It's a tough subject. It takes a lot of time. So I'm very visual, so I like to use things to help me remember. Okay. Yeah, and turn it in. turning thing into food always make things more interesting well yeah i like to eat too so i'm a big foodie okay so i know i kind of flew through um blood i only spent about eight minutes on it but that's because i want to spend as much time as i can on bone okay and whatever we don't cover for bone i'll continue recording and post it for y'all okay so there are Two types of bone in the body. Every single bone in your body has both types. So there is compact bone and spongy bone. So if we're talking about the femur, which is the largest bone in the body, we're talking about your skull bones, you're talking about your finger bones. All of the bones in your body have both compact and spongy. How they're arranged will be a little different depending on the bone shape because a long bone is a lot different shape than maybe your skull bones. Okay, compact bone is the bone that we are going to concentrate on. Compact bone is made out of units called osteons. These are repetitive or repeating circular units. So compact bone is going to be made up of osteons. So they're just repetitive circle units. Ostions are going to have some very specific things. Every ostion will have a central canal. This is an area where blood vessels and nerves are going to be found. Does anyone know the fancy name for central canal? The Haversian Canal? Which one's easier to spell? Central. Central Canal. You can use Central, but her version is the technical name. I am fine with Central Canal though. So you said it has a Central Canal which contains what? Blood vessels and nerves. Thank you. Okay. Around every Central Canal, and one day I'll figure out how to change colors on my pen. I think I know how, but it's just going to be clumsy. Around every central canal, we are going to have layers or rings. These layers and rings are known as lamellae. That's plural. Singular would be without the e. So when I look at this particular picture I drew, I have one lamella, three lamella. So they're just layers. You can have ten lamella. I'm just drawing it straight forward. This kind of reminds me of a tree. Don't steal my thunder. Oh sorry. Tree stump. It is. That's exactly what people use. But I have some other ones that are food, so y'all know I'm going to show you the food. I know. Okay. Food and the tree stump. So Bone is very similar to cartilage in that it's going to have those little pits on it. What are those little pits called? Lacunae. Lacunae. So bone is going to have lacunae all over the lamella. So I'm not going to draw it everywhere, but if you look at a picture or you're drawing your own, you can do it. So bone is going to have the lacunae. They're just little pits. But since we're talking about bone, it's not chondrocytes. What is it now? What sits inside of a lacunae now? Osteocytes. Chondrocytes. Osteocytes. Why osteo? Osteo is bone. Osteo means bone. Bone. So it's the same concept. Chondrocytes sit in lacunae for cartilage. Cartilage. Osteocytes sit in lacunae for bone. Same concept, just different tissue. Gotcha. Like visceral, pleural, and visceral, parietal, visceral, pericardial. Yeah, it's basically understanding that some of the functions are the same, just the naming changes. Yeah. Now, osteocytes are living. Bone is very vascular. If you've ever broken a bone, it does bleed. Bone is very vascular. which means we can get blood. to the osteocytes and that's going to bring nutrients and we can take away from the osteocytes, which means that's going to take away waste. So off of the lacuna, you're going to have these little bitty canals. They almost look like eyelashes. And these little canals are called canaliculis, which is just tiny canal. These tiny canals are going to bring nutrients to the cells and take waste away. So blood vessels go through these tiny, tiny canals. So osteons have that central canal. They have rings called lamella. They have lacunae. And in those pits, we find osteocytes, and those cells are living, so we need to make sure we get nutrients to them and waste away from them. And that's going to happen through those tiny canals called canaliculis. Now, compact bone are these very neat circular units called osteons. Spongy bone does not have osteons. instead the word spongy I want you to think about a kitchen sponge it's very porous lots of little columns absorbing spongy bone is gonna be made up of units called trabeculae trabeculae are these columns so each of these little columns, that's a trabeculae. And do y'all see all these holes in the trabeculae? Right here, right here, here. These holes are going to be filled with red bone marrow. What loose connective tissue fills red bone marrow? looks like cherry blossoms. Reticular. You got it. Sorry, can you repeat like the last five seconds from made of columns of trabeculae? Yeah, so spongy bone lacks osteons and it's made up of columns, bony columns called trabeculae, and all those holes that you see between the columns is going to be filled with red bone marrow. Okay, thank you. And red bone marrow is supported by reticular. Okay. Now, I want to make a very important point here. Trabeculae spongy bone lacks osteons. That doesn't mean it doesn't have the same parts, though. They're just not organized in a circular unit. It still has lamella. It still has lacunae. It still has osteocytes. And it still has canaliculis. It has all of the same parts except for what in the center? Osteons. Central canal. It has no central canal. And that is because... Trabeculae are not always going to be circular. They may be oblong. They may be almost linear. So they're just not repetitive circular units. They're gonna be whatever the shape is of the column. So if it's real long and skinny, if it's really large and oval, it just depends. So spongy bone and compact bone. have a lot of the same parts. Okay, so here is spongy in this picture, here is compact. Okay, does compact bone have an osteon? Yes. Does spongy bone? No. Does compact bone have trabeculae? Yes. No. No. No. No. No. Whoa, sorry. Does spongy bone have trabeculae? Yes. Does compact bone have lamella? Yes. Does spongy bone have lamella? Yes. Do they both have canaliculis? Yes. Do they both have lacunae? Yes. Do they both have osteocytes? No. Oh yeah, they do. So they have to because they're living and that's going to maintain them. So here is spongy bone. It has osteocytes keeping it alive. And then here is my beautiful pictures of compact bone. They have osteocytes in them. So both have osteocytes. So if it's bone, it has to have those cells maintaining it. So the only difference between spongy and compact is basically the shape of it and how it is built in the sense that compact is repetitive circular units. So here's one osteon, here's an osteon, here's an osteon. So they're just repetitive circular units. And spongy bone lacks those. Instead, they have these columns called trabeculae. Okay. Now, you only have to recognize compact bone under the microscope. You are not learning spongy bone. Do y'all see these circular units here? Yes. Okay. They're not perfect. These are bone. Okay. Do y'all see how some of these units are kind of like weird shaped? Yes. Okay. That's because your bone. remodels itself every six months. So some of these osteons are older and they're being removed. So like this particular osteon is being broken down. Fascinating. Now your whole bone doesn't get remodeled in six months. Parts of it does. So like you have basically every few months, parts of your bone are brand new. Now this is just one. big osteon blown up. What are these areas in the middle of each osteon? The central canal. Good job. What's the fancy name for it? Aphasia canal. I don't know how to pronounce it. Aversion. Yep. Okay. Now, do y'all see these darker spots here? Yes. Okay. Those are the little pits. What do we call those little pits? Lacuna, lacunae. Both pronunciations are correct. Lacuna is singular, lacunae is plural, so don't stress about that. Now, what cell would sit in that pit? Osteocyte. So this is a little different because in cartilage you could really see the chondrocyte. In this you can't really see it, so you have to pay attention to the questions. If I say identify the pit, I am looking for the osteocytes. Lacunae. Lacunae. Lacunae. Oh. Because the pit is the little area it sits in. But if I say identify the cell, the cell would be osteocytes. Oh, okay. Okay. So if I say the pit, it's lacunae. If I say the cell, you're identifying osteocytes. Because there's no way to... differentiate them in the picture. Okay, now you can see the lamella because you can kind of see the layers. They're not perfect, but you can see the layers here. It's almost impossible for me to ask you the layers on these because I would have to give you a very long definition of what the pointer's on, which gives you the answer. So... We also have models that I'm about to show you. We use a model for some of the stuff. It's easier to see the lamella and the canaliculis on a model. Now, before I go to that model, these are things that I think looks like it. So everyone already said this one. What is this one? The oyster. Trace don't. Trace don't. Okay. Does anyone remember this yummy stuff? Absolutely. Okay. And this is going to show my fun side of me. Does anyone know what that is? Lacunae. It looks like cake pans. Okay that is the best answer that you could give me. Have anyone stacked up dog bowls? Very close. This is a collapsible shot glass. Wow. However, dog bowls works, cake pans work. So if you google collapsible shot glasses you'll see them. That's what it reminds me of. So these are just different ways for y'all to think of it. This is from our lab. You can see we got our central canal right here. This is just one very enlarged osteon. What is this pit right here that I'm circling? And then what is the cell in the pit? Osteocyte. Do y'all see this little cracks all here yes what are those cracks good job okay now i think it's really hard for me to put a pointer on the cracks without having to like give you again the whole definition so we have models so this is the top view of the model can you see how this is all circular each of these is what a single what Lamella? Well, they do have lamella, but what is the whole unit? Compact bone. It is compact bone, but what is each of this unit called? Osteon. Can I get the osteon? Yeah. Osteon. Okay. So, y'all were saying things that were correct, but the whole unit is an osteon. Okay. Now, do y'all see how on this it's showing you the layers of the osteon? This one's just showing you more. What are those layers called? La Melle. La Melle. Yeah, that's it. And so you see how it's kind of easier to see certain things in the model. Now you can see all these little pits. What are those pits? And then do you see in this particular one over here they're filling the lacunae in with little brown dots. What are those cells? Osteocytes. You got it. And then what is in the center right here of each osteon? Haversian canal. You got it. Okay. And then here's a side view. Y'all see each of these layers? Yep. Okay. So each of these is, these kind of, we call these the ant mounds. Each of these is one osteon and they're just pulling them up to show you the layers. What are those layers called? Lamella. You got it. Okay, so I just wanted y'all to see that it's sometimes easier to see this on models than to always have to look on a microscope. That's all you need to know on the models is just being able to say lamella, canaliculis, osteon. And I have these models in the exercise three notes and activities that you can practice on. OK, so we have three minutes left. I'm going to use our three minutes. We have a few questions. I want you to throw the answers in the chat. OK, first question I lied. We only have one question. okay okay so everyone that's put their answer in scott correct the answer is d bone and cartilage okay so we have successfully covered all of your tissues. I'm going to do a real quick zoom to the beginning. Almost there. Okay. We covered three loose areolar adipose reticular, three dense, dense regular, dense irregular, elastic connective tissue, three cartilages. piling cartilage, elastic cartilage, fibrocartilage, two types of bone, compact and spongy. Under the microscope, you only identify compact. And we only covered one type of liquid, which was blood. Okay, so this is part of your test tomorrow. Okay, I'm going to stop recording, and then I'm going to open up for questions. Let me stop this recording.

So collagen is going to be the background, okay. The foreground we're going to see these thin pencil lines popping forward. Do y'all see those thin pencil lines? It almost looks like someone just took a pencil and drew all over it.

Yes. Yeah. Okay, these thin pencil lines are going to be which one?

It will be the elastic fibers. Those are the elastic fibers. So the elastic fibers you can see are kind of staining darker, like a purplish color, and they almost look like they're popping forward.

So, collagen looks like it's filling the background information and elastic looks like it pops forward. So, on the test, I could ask you these questions. I could say, identify the fiber at the pointer tip. So, you know, imagine that there's a pointer tip, not just an arrow. Or it could be that I drew an arrow and I labeled the arrow one.

Identify the fiber labeled one. I could say identify the cell labeled two. So on the test you're going to be asked to identify different structures.

I could say identify this tissue. What would the tissue be? Areola.

Areola. I can ask you a location and a function. You get those directly from the textbook. Okay.

So that would be like a fill in the blank, like when you ask the location and we can just list around blood vessels or nerves. Yes. Yeah. And just remember that if you said around blood vessels, but you change that to be something else that means the same thing, it would probably count it wrong. And then I would have to go in and give you the credit.

So don't stress too much about, you know. what your answer, how you write it. Just worry about getting your knowledge down. Okay.

I don't want y'all to stress about, oh my God, I can't get the exact answer correct. I go in and I hand checked everything. That's why it takes a while to grade them. Okay.

So I'm going to continue on with my analogies. I'm going to give my husband credit for this one because I cannot think of anything that looks like areola that's food. I always think it kind of looks like a spider web to me, but my husband told me he sees spaghetti, so I went with that. I don't really see it, but it may help you, it may not, but basically the spaghetti would be the fibers and then all the little chunks of whatever's in there would be the cells.

So thanks for laughing at that. I'll tell my husband that someone agreed with this. I definitely agree.

No, but the little purple whatever in there in the spaghetti looks like the... The picture. The, what you call, the nucleus?

Wait, the macrophage? The fibroblast? Yeah, the fibroblast. Yeah, the cells? Okay.

Okay. So, do y'all see how there's a pointer in the areolar tissue right here? This is a pointer tip? Yes.

Okay. Yes. pointer tip is pointing to a cell in the chat put a for fibroblast or b for macrophage in the chat put a for fibro or b for macro great job y'all are doing great okay so people put a for fibro really good okay so that's our first loose connective tissue.

Our next loose connective tissue is adipose. Adipose connective tissue is what? What do y'all commonly call this?

Marshmallows. It is marshmallows, but what is it? It's bone.

I say bone. It's fat. Okay, now while adipose tissue is usually my class's favorite because it's pretty easy to recognize, the questions asked about it are where the students often get confused.

So this tissue is known as adipose tissue. Remember that tissues are made up of cells. The cells are called adipocytes. What does site tell us?

You got to maintain. And then adipose tells you fat. So what are the sites maintaining in your body?

Fat. You got it. Okay.

So. Adipocytes are basically these big circular cells and they are filled with a big old fat droplet. That fat droplet is so big it pushes everything to the side so all you really see is a white circle with maybe a nucleus stuck to the side.

Inside is the fat drop. So the white that you see is the fat drop. So on this picture, this whole cell is one adipocyte. Okay, here's a nucleus. Here's another adipocyte.

Here's a third adipocyte. So each of these cells are a single adipocyte. What is this white stuff that fills the middle what is this right here fat deposit that is your fat so some people call it a lipid droplet some people call it a fat droplet some people go fancy and write triglyceride any of them are fine okay so let me tell you what the questions are like if i said identify this tissue what would the tissue name be apples loose tissue.

Oh, loose tissue. Nope, nope. Go. You were right the first time. You always want to go specific.

Oh, adipose. Remember, loose is a group that defines characteristics. It defines that we see a lot of cells.

Okay, if I said identify, here's my pointer tip right here, identify the cell at the pointer tip. I did both sides. What is stored in the cell at the pointer tip? What is stored in the cell at the pointer tip?

Fat drops. Perfect. So when we talk about this tissue, the name of the tissue is adipose. The cells are adipose sites.

And the storage is a fat drop, lipid drop, however you want to call it. So if we ask the function, the function is just, I guess, storage. It stores fat around organs.

That's a function. It actually has quite a few different functions, but that's a function of it. All right.

So let's go to our typical analogies. You all see the similarity? Yes.

Okay. So when I see adipose, I see marshmallows. So that's just my little analogy.

Now, when you look at adipose tissue, so we're looking at this picture or we look at these pictures, the actual tissue itself is pretty white. So there's actually two types of adipose tissue in the body. What we're looking at in these pictures and in that picture are called white fat. But there is another type of fat in the body called brown fat, also known as batty tissue, brown adipose tissue.

Brown fat is only going to be found in newborns. So brown adipose tissue is found in newborns. It has more mitochondria. and more blood vessels than white fat. You say more mitochondria?

And more blood vessels than white fat. Now as the newborn develops, brown fat converts into white fat. And you do have a little bit of brown fat in the body as adults, but every person's different.

So you may have 0.05% and someone else may have 2% of brown fat. So it's not very common in adults. But the reason newborns have brown adipose tissue or brown fat is the newborn needs to keep their temperature higher.

They need it to thermoregulate. So brown fat is used for thermoregulation more than regular white fat. So brown fat is used for thermoregulation.

You are not going to have to identify brown fat. You only have to recognize regular white fat. What does more BV mean?

What is what? Say that one more time. More BV.

Blood vessels. Oh, blood vessels. Thank you.

Sorry. Thank you. So I just want you to think. cellular cellular respiration is how we make most of your body's ATP. ATP can only be made if we have nutrients specifically glucose that's the easiest way to make it brought to the mitochondria and oxygen.

So the more blood vessels we have the more sugar and the more oxygen with the sugar and the oxygen the mitochondria can make more ATP. that ATP is used for thermoregulation, so keeping babies warm. Now this picture, the ones that are book ending on either side, this is brown fat.

It looks totally different than white fat. Yeah, it looks purple. But remember that's a stain, but I know it doesn't quite look the same. The fat drops are much smaller. They're what you call bi-trioculated, meaning that there's lots of little fat drops instead of one big one.

So you don't have to recognize it. I just wanted y'all to see the difference between them. Should we remember that big word or no?

I just want y'all to see the difference and understand why there is brown fat. Okay. So would one of the questions be like, what is a function of adipose tissue? And then we will have to write out one of the functions.

So functions are primarily physiology tests, whereas it's going to be like a true false, right? I'm sorry, say that again. And that's going to be more of a true false, true, false, multiple choice matching.

So the physiology tests are like what you would. be used to taking for a regular test like scantron usually except for we're online so there's no scantrons so when you think functions think physiology when you think anatomy think mostly practical okay which would be more identifying yeah practical is more anatomy so you more identify i have that all written in the announcement I'm so just a little confused. I'm sorry. Okay, so if you go to the announcement that I posted for test one, it talks about the differences between the practical and the physiology, and it's explained in the syllabus schedule and the addendum. And she tells us what's on it, how many questions, multiple choice, how many minutes, each part.

She tells us the practical, what's on it, and the anatomy that you have to label. She break it down. Yes, I saw that. I just needed a little bit more clarification. Yeah, and there's also a study guide that will help guide you.

It's just a guide. I don't, I personally don't really believe in study guides, so it's just to guide you. Okay, so we've done areolar and we've done adipose.

Our final loose tissue is reticular. Now, when you look at reticular, What you're going to see are lots of cells. So remember, loose means we see tons of cells. It doesn't mean fibers aren't present, it just means that we see a lot of cells. Based on the name reticular tissue, what fiber do you think this has?

Fiber. It does have fibers, but which one? Reticular. Yeah, okay.

So, reticular tissue has reticular fibers. If you remember, I said that reticular fibers are short and wavy. These little cracks in here, those are all reticular fibers.

So, I kind of think they just look like little cracks in glass. All of these that I'm tracing, those are all the reticular fibers. Okay, all of the circles behind them are all of the cells. And you can see that there are tons and tons of cells.

That looks like pink peanut brittle. Oh, that's a good one. That's a new one. Pink peanut brittle. That works.

Okay, now with reticular tissue. Since it has reticular fibers and their job is kind of a supporting fiber, we're going to find reticular tissue in hollow organs that are small. So lymph nodes, you're going to find it in the spleen, parts of the liver.

The liver is not small, but you don't find it everywhere. So it's a supporting tissue. Now, one of the most important. Sorry, Veronica, you had something?

No, I said spleen, liver. And what else did you say again? Lymph nodes. Okay.

Now, since reticular is found in a lot of places supporting, one of the most important places that we find it is in your red bone marrow. So, it is found lining the area of red bone marrow. It is very important in blood. production.

So it's kind of a filtering support tissue for red bone marrow. It's a supportive what? It's a supportive filtering tissue and it's located with red bone marrow.

So really important with your bone marrow. Red bone marrow. Okay.

Now we have seen this tissue for those that are also in my lecture. We've kind of gone over some of my analogies before. So I like all food analogies, but not everything has food all the time.

So this one, cherry blossoms. And then I also kind of think clusters of fruit. That's just another description that I kind of think of. And now I'm not sure who said it, but who said the peanut brittle? Stephanie, if it's Morris.

I see that too. So maybe I'll add that to my collection next time I teach. I think the cherry blossoms are like spot on because the branches look like the fibers and then the blossoms look like the sows.

So. Lots of different things you may see. Kind of depends on your imagination.

So we have covered three loose tissues. We've covered areolar, adipose, and reticular. Now, I'm going to go through just a few questions. What's the function, ma'am?

Sorry. Where do you get the function? In the red bone marrow.

No, but where do you find the functions? It's on page 127. Everything's in your textbook. Because of time, I'm going over 11 tissues today.

I don't have time to give you all everything, so you go straight to your textbook. I'm only covering things that I'm highlighting that I think are super important. Sorry. No, it's fine. There's no way I can go over everything in a three-hour period.

Okay, so the next... thing is going to be just a few questions just throw your answers in the chat and then we'll move on to dense so here's your first question tyrone's getting fancy and answering with the full word okay Now we're going to go to the next question. Everybody that I've seen has put C, which is reticular, and that is correct. Here's the next question. Okay, very good.

Everybody was putting B, areolar. Areolar is the scotch tape of the body, not the duct tape, because it's not that strong, the scotch tape. Always go with the best answer that you see. I have to take my watch off because I get buzzed every time y'all answer a question. It's connected to my Apple Watch Teams.

Okay, good job. So while loose is a correct answer, it's not the best answer. The best answer is going to be reticular because reticular is a specific tissue. So you will rarely, if...

ever with me be answering the term loose, dense, cartilage, liquid. You will always be doing a very specific name of a tissue. Okay, so we've done loose.

Loose is lots of visible cells, loosely intertwined fibers. So dense is going to be basically the opposite. Dense is going to be tightly packed fibers.

They're so tightly packed that the cells are not as visible. Dense is going to be tightly packed fibers, and they're so tightly packed that the cells are not as visible. Tightly packed fibers that are so packed that the cells are not as visible. Does that mean that there are not cells? present?

No. Do we see them as easily though? No.

You got it. Good answers. Okay, so we have three denses. Dense regular, dense irregular, and elastic. With the word elastic, be really careful.

We have elastic fibers, elastic connective tissue, and elastic cartilage. So you just want to be really careful when you use that term elastic and make sure that you put an ending on it. Because you don't want to confuse elastic fiber with elastic connective tissue with elastic cartilage. So you just have to be careful with naming that.

All three denses are going to be used for strength. So which fiber are we going to have tons of? Corn. collagen good job y'all collagen good job so who is collagen's buddy who does collagen like to hang out with elasticity elastic now just because it hangs out with elastic does not mean we can always see the elastic okay collagen is a much more forward seeing fiber we see that one more easily so we're going to go over the first one which is dense regular okay dense regular is going to be collagen fibers running in a regular pattern so they're all running the same direction so collagen fibers running in a regular pattern that pattern can be up and down left to right it can be at an angle but no matter what what we're seeing is that they're running in one direction.

So in this particular picture, both of them are running up and down. I could actually make this picture and it can run left to right, but the similarity is that they're all running in one direction. Now, since we have so many fibers, what type of cell makes all these fibers?

collagen fiber bundles yeah so the cell would be uh was it chelsea that just said that or brianna brianna brianna so brianna just said fibroblast so remember if i'm asking for the word cell The word cell is going to be a blast, a site, a clast. So fiber blasts produce the fibers. So what we're seeing in here is we're seeing not as many cells, but we're seeing lots of smushed fiber blasts that are kind of looking like smushed pancakes because they're being smushed between all the fibers that are tightly bound together.

So we still have a lot of cells, but the cells are not quite as visible as they were in loose. Now, since these fibers run in one direction, are bidirectional, what happens is that they're really strong in the direction they run. So in this picture, they are really strong going up and down. But the minute there is...

pressure from the left or the right they're not as strong anymore and they can easily tear so i want y'all to think about the acl have y'all heard of the acl yes okay it's a very common ligament that is a super common injury so the acl is a ligament in your knee you also have a pcl and mcl so you may have heard those too. This is a very common injury in football, soccer, and that's because this ligament runs up and down. So when your knee gets hit from the side, the ligament's not as strong from the side, so it causes tears.

So we find dense regular in your tendons and your ligaments. Do y'all know the difference between tendons and ligaments? One connects bones to bones, one connects bones to muscles. Which one do tendons do? Bone.

Bone to muscle. Okay. Bone to muscle. And then ligaments are going to do bone to bone. So tendons and ligaments, they're the same structure.

They're both made out of dense regular, but tendons connect bones to muscles. Ligaments connect bones to bones. So have y'all heard of the Achilles tendon, that huge tendon in the back of your leg going from your calf to your ankle? Yes.

That tendon connects your heel bone to your calf muscle. So bone to muscle, heel bone to your calf muscle. Wait, say that again. Achilles?

Oh, that was just an example. The Achilles tendon connects your calf to your heel bone. So calf muscle to heel bone, whereas ligaments connect bone to bone.

They're made out of the same thing. They're just different locations. So let's do another analogy.

This is dense, dense regular. And what are these candies? Twizzlers. Collagen.

Wow. So Twizzlers, which are the collagen. And just pretend that all these little like shadows between all these shadows are going to be the cells.

What are those cells called? Macrophage and Iberblast. They're only going to be fibroblasts on this particular picture. So this is just an analogy, y'all. This is not science.

This is just ways to kind of get your memory thinking to separate all of these. So in this picture that we're seeing right here, this picture, remember that this is collagen fibers all running in one direction. bidirectional up and down in this picture.

And then these are what cells? Fibroblasts. You got it.

Okay. So dense regular is when the fiber's running a very consistent pattern. What do you think dense irregular is going to be? Do you think they're going to have one pattern?

No, it might have. No, they look more chaotic. Might have different points. OK, so I heard chaotic.

I heard different. And what did you just say Jeremy messy? Messy. All of those are great descriptions.

Quick question. Yes. For the dense regular, is it always going to be dense collagen fibers? Yes, it's going to be collagen.

There is elastic present, but we rarely ever see it. Okay, thank you. So basically, you were seeing pink fibers.

Now, if we were actually in lab, and I don't know why I don't have a picture of this, but if we were actually in lab. and we were using slides, there are a few slides that I love that don't have any stain to them. And the reason that's good is because you only see the structures, you don't memorize color. And if you can let me see if I can find one online, just because it's really important to start seeing things.

oh see all these are stained we have some really nice one in the book is is there one in the book that's not stained it's just kind of like a brownish yeah it's actually clear and i i thought i thought i may have had one i probably have one somewhere in one of my files it's just finding that file won't be that easy i'm just gonna look super quickly because we don't have time for me to really look for a long time If I had this, like, if it was my choice, we would not learn stains at all, but that's not my choice. So most of our stuff is stained. What's wrong? At one point, I did have this picture somewhere, and I don't know where it is.

Okay, well, it's not on my immediate pictures for class. But when they're not stained. It's you just see the direction and the shape of the fibers.

You're not seeing any pink. Okay. Oh, I'm not finding anything. If I find it, I'll send it to y'all via email.

I don't want to waste too much of y'all's time me finding what I like to show y'all. Okay. So our next one is dense irregular and it's just a mess.

We still see collagen but the collagen is no longer going in one direction. The collagen is going, it's not going up and down or side to side anymore. It's going in all different directions.

So it's kind of like swirly. So each of these arrows I'm drawing are collagen fibers going in different directions. And they're bundles, they're not single fibers.

Now the reason this is so important is because when collagen goes in all different directions, no matter which way it is pulled, it is strong. With dense regular, it's only strong in the direction it runs. With dense irregular, it's strong in every single direction. So your biggest portion of your skin is your dermis.

So both of these pictures here are showing the dermis. So this whole picture is the dermis and all of this is the dermis. Your dermis is the... The...

bulk of your skin and if you think about your skin you move it constantly it goes around your legs your arms your torso and you move it in all different directions all the time it's twisting and it doesn't tear that easily because the collagen's in all different directions so it's very strong it's one of these stronger tissues in your body the whites of your eye is known as the sclera That is also made out of dense irregular. And then the periosteum and the perichondrium. What does the word peri tell you?

Outside. Close. Very close, Veronica. Surrounding. Running around.

Yeah. It is on the outside, so it goes around something on the outside. So periosteum is going to be going around what?

Okay. What does ostium sound like? Around bone.

And what does perichondrium tell us? Cartilage. So basically around your bone and around your cartilage, you may have a layer of dense irregular tissue surrounding it.

You may, not all of it does, but most of it does. So around bone and around cartilage, you may have dense irregular surrounding it because it provides strength and structure. I'm sorry, periosteum is the outside of bone? It's a layer of tissue on the outside. And perichondrium is the same, but it's on cartilage.

So when you look at dense irregular, the fibers don't run in one direction. They run all over the place. And I think it looks like tenderized meat.

Mm-hmm. If you don't see it, it's perfectly fine. This is just what I see when I look at it. Yeah, but it looks more like the one covered with a lot of fat, though.

Yeah, that fatty area is kind of like the ground substance. Mm-hmm. So this is just what I see, y'all.

But it's not close. Yeah. I also see in my head cotton candy just because it's very airy and the fibers of the... sugar go in different directions. Okay, so we've done dense regular, and we've done dense irregular.

The last dense is elastic connective tissue. So this is elastic connective tissue. Lasagna. Lasagna, which I have a picture of in a second. Okay, when y'all look at elastic, you see two major colors.

Do y'all see kind of a background pink? A little bit. A little bit?

Okay. What fiber stains pink? Glitch.

Areola. Collagen? Well, areal is a tissue. Collagen, collagen.

Oh, collagen, I'm sorry. Collagen. Okay. And then what fiber are long and skinny and staying dark and pop forward? Elastic.

Elastic. So elastic connective tissue is going to be both elastic and collagen bundled together. But the reason we see the elastic fibers is because there's so much more of it. Now, we find elastic connective tissue in areas that need a lot of stretching but recoiling.

So we find this in your major blood vessels. So like your aorta is your largest blood vessel, and we need that blood vessel to get bigger and then get smaller as blood's pumping through it. So we find elastic connective tissue in areas that need to stretch and recoil.

Stretch and recoil. Now in this there are two major fibers we see. We see that kind of purple skinnier fiber that pops forward. What is the purple skinnier fiber that pops forward? Elastic.

Elastic. Elastic fibers. And great and then that background is going to be that pink and because Anything that stretches and recoils, we need to have it be strong so it doesn't tear.

That background kind of pink color is going to be which fiber? Polymer. You got it.

So I personally see both. Oh, I forgot to tell you all this. Most of the pictures I'm using, most, not all, are from our lab.

So they're either I've taken them or students have taken them. Not all of them are, but most of them are. that's just so y'all can kind of see the quality that you will see on the test.

So just be reassured that we use good pictures on the test. I don't use some of the crappy stuff. So when I look at elastic, I took two different stains because one looks like lasagna to me and one looks like turkey bacon.

So this is the one that looks like lasagna to me, one that's darker in color. If you don't see it, it's not a big deal. Okay, so I see lasagna when it's really stained heavily.

Oh, ramen's good. Ramen noodles is really good. Jocimer said ramen.

Yeah, before you take it apart. Yeah. And then this one is the lighter stained one, and I see turkey bacon. Exactly.

If you don't see turkey bacon, don't worry about it. I see ham, too. Like when you want a ham sandwich.

So remember that these are just kind of silly things that I use to help with, you know, association. So these are just different ways to help you all kind of remember stuff. OK, so we've done three denses. We've done dense, regular, dense, irregular and elastic connective tissue. We are going to go through just a few questions.

Just write that answer in the chat and then we'll move on. OK, so here's your first question. Okay, so the a torn ACL is a torn ligament.

So think about what ligaments and tendons are made out of. Okay, so everyone is putting B, which is great. And even someone that put A said, oops, B, way to go. Okay, so an ACL, anterior cruciate ligament. Okay.

Ligament tells us it's dense regular. Okay, and most people, I'm gonna give just another second to put in. Okay, so most people or everyone I think put D. So D is tendons and ligaments. Which one, which dense tissue would we find in the dermis of the skin, the bulk of your skin is which dense tissue?

Tense irregular. Good job. What is padding that protects our organs? Which tissue is the padding that protects our organs?

Pusheen. Adipose. Good job, good job Yuri.

And then what tissue do we know we find supporting those small hollow structures such as the spleen and lymph? It looks like cherry blossoms are clusters of fruit. Reticular.

Reticular. Good job. Okay. Okay.

We're going to take just a short break, like a two-minute break. Just go stretch, run to the bathroom if you need to, because we still have five more tissues to go. So just take a real short break, and then we'll start back up in about two minutes. Thank Okay, it's been two minutes.

Are we back? we're ready to go okay so we've done loose we've done dense now we're going to hop into cartilage cartilage is a very unique tissue because it has certain things we haven't seen yet okay it also is that tissue that's kind of the exception to all of the connective tissue rules it is avascular what does that mean It doesn't have a lysopon. It doesn't have blood. Yeah. Okay.

So it's avascular. It lacks nerves. And we can find it lining structures. Not all cartilage does that, but some cartilage lines structures. So it's kind of the rebel of your connective tissue family.

Now, cartilage is going to have some very unique. characteristics that helps us identify it. The first characteristic is that it's always going to have a ground substance.

Now all tissues have this, all connective tissues have it, but cartilages you can see really well. And in this particular picture I have, the ground substance is all the purple that surround these little white holes. The ground substance is made out of chondroitin.

sulfate. So what does chondro tell you? Cartilage.

Yep. It means cartilage. So if you see that word chondro, it's referencing cartilage. Now the chondroitin sulfate may or may not have fibers in it.

In this particular picture I have up here, there are no fibers, but there can be, just not the one that I have up here. Now, Now, something that's unique to cartilage and we'll also see it in bone is, do y'all see all these little white holes? These little white holes are called lacunae. Lacunae are just kind of like little divots that have cells that sit in them.

These are the cells that maintain cartilage. What cell maintains cartilage? Lacunae. Well, that's what they sit in, but what cell maintains it?

Chondrocytes. Chondrocytes. We know cytes means maintain, and we know chondro means cartilage. Okay, and you can see the lacunae over here too.

Now, a lot of these lacunae on this last picture are... empty and that just means the chondrocytes died so if you don't see a cell in a lacunae it's fine it just means the cell died okay now the last thing is that cartilage can have a perichondrium and we just kind of went over this what's the word peri mean surrounding what does chondro mean okay So two of the three cartilages we're going to learn will have a perichondrium. The perichondrium is made out of dense irregular, which is just one of the last tissues we went over.

Not all cartilage has a perichondrium. Two of them do. The two cartilages with the perichondrium are hyaline cartilage and elastic cartilage.

Now, why is a perichondrium good? It is good because it contains blood vessels. It is protection too.

So whoever just said protection, that's another good answer. So perichondriams contain blood vessels. What do cartilage tissues lack? Blood. Blood supply.

Yeah. Blood vessels. Yeah. So if cartilage is damaged. they don't have blood vessels in it to heal it.

So all of the nutrients and cells, they have to diffuse from other blood vessels. If the perichondrium is present, that means that there are blood vessels that are right next to that cartilage. So the chances of them healing is going to be faster and better.

So these are just general characteristics of all cartilage. they're gonna have a ground substance they're gonna have lacunae which are just these little pits that hold cells and they can have a perichondrium they can now what is this tissue right here y'all that's above the perichondrium adipose say that with confidence yeah so The one thing that we are missing by not being in the lab is that at the end of classes, I usually pick certain tissues, actually not tissues, certain slides that will have about eight tissues on it. And then I'll go through them and test y'all. And it's great because regardless of where it's from in the body, you know these tissues and you're able to go through them. Now, we have three cartilages in the body.

Hyalin, elastic, and fibrocartilage. Hyalin and elastic are the only ones with a perichondrium. Fibrocartilage does not have a perichondrium. okay do any of these have blood vessels though do any of those cartilages have yes no which one i heard no and i heard yes what is about cartilage is considered oh okay i was thinking about the perichondrium yep and the perichondrium does have those blood vessels but it's not cartilage it just surrounds Right.

So we are going to go over Hyland first. And anytime you see a pointer in a picture, that means that it was taken in our lab. So these are very good cell slides.

This is Hyland cartilage. Hyland cartilage is the most abundant cartilage in your body. So you have the most of it. It's also the weakest. So go ahead and touch your finger to the tip of your nose and wiggle your nose.

That is hyaline cartilage. Pretty flexible. Do y'all know how babies are super flexible?

Like they can literally like turn into a pretzel. That's because their bones are made up of hyaline cartilage. They haven't fully ossified.

So they haven't fully hardened into bone. And yeah, that explains why they can be a gymnast at a young age. And then if you the ends of all bones, all long bones are covered with highland cartilage and it's called articular cartilage. So the ends of all long bones are covered with.

thin layer of cartilage called articular cartilage. It is made out of hyland, but it's named for its location. So articular cartilage is hyland cartilage that lines the ends of bones. Articular cartilage is hyland cartilage that lines the ends of bones. When we look at the cartilage, what are each of these little pits called?

Lacunae? You got it. So if it's just an A that's singular, if you put an E on it, that's plural. I'm really not picky, but I will give you a warning that some teachers are OK now in a lot of the lacunae were actually seeing cells.

What are those cells? Fibro... Okay, well what tissue are we talking about?

Cartilage. So what would the beginning be? Chondro...

And then what cells are going to maintain the cartilage? Chondrocytes. Okay, so all these little nuclei that we see in the lacuna, those are chondrocytes. Now... Does cartilage have fibroblasts?

Yes, but we're not going to see it. Wait, say that again, Dr. R. I said that cartilage can have a fibroblast, but we're not going to physically see it. We're only going to see chondrocytes. Okay. Now, all of the stuff between the lacunae, so in this particular picture, all of this purple.

and in this particular picture kind of this pinkish color that is filling everything between the cells what is that going to be the matrix okay and the matrix can have both fibers and ground substance ground substance yeah specifically this ground substance is known as chondroitin Sulfate. So, doesn't matter what picture we're looking at, all of this stuff that surrounds the lacunae is all ground substance, and it's known as chondroitin sulfate. So, do all cells have lacunae? All cartilage has lacunae, and the cells sit in the lacunae. the cells sit in there so the lacunae are the cells kind of like living space okay all catalyses have lacunae now is the ground substance going to be made of the chondroitin sulfates and other areas or solely in the cartilage a chondroitin sulfate is solely for cartilage but there will be other stuff in it So it will also have dermatinsulfate, hyaluronic acid, but we're only focusing on chondroitin sulfate.

Okay, thank you. Now, for this particular cartilage we're looking at, it's hyaline. You're not seeing fibers in the ground substance. So hyaline cartilage, you cannot physically see fibers. Fibers are not visible.

So for hyaline cartilage, fibers are not visible. Now I'm just going to change pictures and show you two more pictures of hyaline. So Dr. R, what is the pink on top of the picture to the right?

This one right here that my mouse is going over? That is your perichondrium. So it sits above?

Yep. It actually surrounds it. So it's on both sides. So it would be down here if I had the bottom of this picture too. Oh, okay.

Okay. And so the highland part is in between there? Yeah.

So this is the highland. So let me go back. Nope. Those pictures.

This one's a little bit better. Let me erase all this and show you. This one kind of shows you everything. From here to here is your hyaline cartilage.

And then this area is going to be your perichondrium. Okay, now I see it. It does look different. I see it now.

It just depends on how much I blew up a picture. So this is hyaline cartilage. Again, it doesn't really matter the stain.

You're not seeing fibers running in the ground substance. Now, fibers are there, there's just not a lot of them, so they're not very visible. So that's why we say you cannot see them.

What are all of these circles called, these little pits? Lacunae. Lacunae. What sits, what is the cell in the pit?

Chondrocytes. Chondrocytes. Okay.

Now, the cartilages are just something that I'm going to tell you all, spend time on. Okay? Spend time looking, Google, see tons of pictures. So this is hyaline cartilage.

Our next one. is elastic cartilage. Both of these pictures came from our lab. What I want you to notice is in the ground substance, you're seeing individual fibers. So all of those kind of lines that you are seeing, those are all fibers.

Based on the name elastic cartilage, what type of fiber do you think you're seeing? Elastic. Elastic fibers.

Whoa, I don't know. I'm learning my new computer still. I just learned that I can then blow things up for y'all. Okay, so elastic cartilage has elastic fibers. It's still really flexible, but it's much stronger.

So everyone take their hand. and grab the outside of your ear, the upper part of your ear. Okay. You see how you can still kind of bend it and fold it? So it's still flexible, but it's much stronger than hyaline cartilage.

And that's because it has those elastic fibers in it. So your outer part of your upper ear is known as the auricle. Some people call it the pinna. Either name is fine. that is where we find elastic cartilage oracle or pinna does elastic cartilage have a perichondrium yes or no no yes yes elastic yes elastic cartilage yes to a perichondrium Okay, now I'm going to show you two more pictures that came from our lab.

These you can see the fibers a little bit better. So can you also kind of see these it almost looks like fray from jeans between the pits. All of those are fibers.

Right here is a fiber. You can see the fibers. Whoops.

you can see the fibers really well in there it looks like a cluster of frog eggs oh that's a good one so we're gonna say frog eggs that looks really that's a really good one um do y'all still see these little pits right here here here what are those pits called lacuna lacunae and what is found inside of them what cell do we find Okay, so I really like the frog egg comparison because my whole master's degree is on amphibians and reptiles. But when I look at this particular picture, I see oysters on the half shell. Yes, indeed. 100%. So again, y'all.

For the cartilages, it's one of those things I just emphasize, spend a little extra time looking at pictures. Okay, so we've done hyaline cartilage, which is the weakest and most abundant. Elastic cartilage is stronger, but it's still very flexible.

Our next cartilage is fibrocartilage. Based on the name. What does it have a lot in it?

Fibers. Fibers. This is your strongest cartilage. Strongest. Which fiber is in it?

What's your strongest fiber? Collagen. Fiber cartilage is full and full of collagen fibers. Just tons of collagen fibers.

That's it. you There's so many collagen fibers, it's sometimes hard to see the lacunae. So, there's just so many of them. Now, these two pictures come from our lab.

This is what our older specimen looked like, and this is what our newer slides look like. You can still see the collagen. In this particular picture, it's blue, it's not pink.

What are these pits called that we can barely see because there's so many fibers? Lecune. And then what are these cells that are staining a pink that we can see really well? Chondrocytes.

Chondrocytes. You got it. Okay. So remember how I said collagen almost always stains pink? Mm-hmm.

I said almost always. This is just an example of when it stains blue. Now, can they stain fibrocartilage pink? Yes.

Here's a picture of it. We personally don't have any pink slides. All of our slides are blue. So I just wanted to show you that it can be pink.

Now, this one came from the web. This is not a picture we took. But what I want to...

emphasizes that it has so many fibers, it is super strong, and it still allows some flexibility. We find fibrocartilage in areas that take just a lot of beating from you. What joints do you know that you just abuse by everyday living?

Your knees and your back. All the limbs. Knees, yeah, definitely.

And I'm going to say vertebrae, which is referencing your back. We find fibrocartilage in areas that need to absorb a lot of shock and take a lot of tension away from all of the movement. So we find the fibrocartilage in meniscus of your knee, which is just a disc of cartilage in your knee.

And we find it in your... intervertebral disc. Intervertebral disc.

So you hear about people talk about a herniated disc or a slipped disc. It's fibrocartilage. We also find it, and this is important for everybody because everyone has this, in the pubic symphysis.

That's a piece of cartilage between your hip bones. So every time you walk, it's not just your knees. Your hips are moving and they absorb a lot of the shock and friction. Isn't your sacrum lined with some type of cartilage? I'm sorry, say that again.

Your sacrum. Is that right? Oh, your sacrum. So between your sacrum and the lumbar vertebrae, right?

above it, you're going to have a fibrocartilage disc. Okay, you do. Okay.

Yeah. Yeah. It's not going to be, it's going to be at the top of your sacrum and you're going to learn those parts soon.

It's called the sacral promontory. Thank you. Now, does fibrocartilage have a perichondrium? No. No.

Super important because that is why you often hear about surgeries. So if you get a torn meniscus, which is a very common injury to the knee, if it's not a bad tear, they'll let it go. But if it's a bad tear, the only way to fix it is surgery.

And that's because these just don't heal that quickly because there's no blood supply near them. And they're so dense, it's hard for things to diffuse through them. So again, with your cartilages, hyaline, elastic, and fibrocartilage.

Just Google these, look at tons of pictures. That's going to be the best way to learn these. So fibrocartilage has no blood supply, right? None of the cartilages do. Okay.

But fiber doesn't have that perichondrium. So there's like no blood supply near it. So it takes it even longer to heal. To heal. Okay.

Okay, so I'm just going to throw up a few questions. Same thing, just throw those answers into the chat room. OK, I got only about 10 of y'all have answered few more answer. OK, so everyone's putting C. That's correct.

Here's the next one. OK, everyone's putting C for this one also. OK, the next tissue we're going to cover is going to be bone and then blood.

I'm going to go to blood first just because it's a lot faster to go through. And that way I know exactly how much time I have left for bone. So I'm going to skip quite a few for a second and go straight to blood.

There we go. OK, so we're going to do blood first and then I'm going to go back to bone. When we think about blood, it is our only connective tissue that we are learning that is going to be what consistency? Liquid.

Liquid. Got it. So when we think about loose, dense, and cartilage, they're all what we consider like gel-like.

I think of silly putty or gum. That's like gel-like. It's solid, but it's flexible.

When you think of bone, it's hard and solid. but when you think of blood, blood has a liquid portion to it. So blood is actually made out of a group of things. It is made out of cells because it is a connective tissue and it's made out of the matrix and the matrix has fibers and the ground substance.

The fibers are very specialized fibers. We did not actually talk about these, so don't stress about them. You'll learn that in A&P too.

But the fibers are very specialized fibers for clotting, so they're not one that we specifically talked about. The ground substance is going to be your plasma. And then the cells, we're going to have three cells we talk about. Erythrocytes, leukocytes, and thrombocytes.

so the first cell is a urethrocyte do you think you're going to get credit on the test if you put red blood cell probably not probably not you need to put your erythrocyte even if you misspell it it's a quarter of a point off so 0.25 if you write red blood cells it's wrong so go ahead and misspell it and just get a quarter of a point off instead of getting it wrong Erythrocytes are the most common blood cell, but they're not even real cells because they are enucleated. I cannot spell today. Let me start that over.

Enucleated. Okay. What that means is that they are without a nucleus.

So red blood cells, urethrocytes, are not even real cells because they lack a nucleus. They only have about a three-month lifespan and does anyone know their function? Transport oxygen to the rest of the body.

Perfect, okay. So red blood cells are the most abundant, they lack a nucleus, and they transport oxygen. They basically look like the pinkish red dots that you see over and over again. Since they're the most abundant, that's what you see the most of.

The next cell is going to be a platelet, also known as a thrombocyte. Platelets are not even cells, they're pieces of cells. So they're like torn up cells. If you take a piece of paper and tear it in pieces, that's like a platelet. You do not need to recognize platelets on pictures you just need to know the function for platelets you only need to know the function you do not need to recognize them in pictures what's the function blood clotting because we only look at magnification of 400. And this right here at 650 is a platelet.

You don't know if it's dirt on the slide or if it's actually a platelet. So I just require y'all to know the function, not to recognize them. And our last cell, which is a true cell, is a leukocyte.

Leucocytes can be spelled two ways. So if you spell it L-E-U-C, that is fine. So it can be a K-R-C. What do y'all notice about a leukocyte? There's two big things about it that are very different.

It's larger and it actually contains stuff in it. Okay. The first thing is it is larger. They are so much bigger in size.

And then what is it that it contains inside of it? What does a red blood cell not have? A nucleus.

And all leukocytes will contain a nucleus. Now, there are lots of different types of leukocytes. All you need to know is leukocyte. That's A and P2 that you learn the different types of red blood cells. of white blood cells.

Now remember that this picture we're looking at is much larger than what we normally see. So I'm going to go to pictures from our microscopes to show you the difference. Now on this particular pointer right here in The chat area, I want you to put A for erythrocyte or B for leukocyte. I'm just writing RBC and WBC right now for shorthand.

So A is erythrocyte, B is leukocyte. So what is the pointer on in that picture? A is erythro, B is leuko.

Y'all are really rocking out today. I have really good feelings about this test. Okay, everyone's putting leukocyte. That's correct. Can y'all see that they're much bigger in size?

That's a leukocyte. Leukocyte. Leukocyte. Here's one on the edge.

There's a few things that tell you right off that it's a leukocyte. It's larger. You can see a nucleus inside of it.

And there's not that many of them. What are all of these that we see everywhere that are just basically the whole picture? Arithrocytes.

You got it. And then what is this white fill in the spot, fill in the between the... Plasma.

Those are plasma. Plasma. Perfect. Okay. Now, I've kind of stretched far with this analogy, y'all.

I couldn't really get one in my head, so I went for M&Ms and Smarties. Oh, my goodness. I had stressed a little bit, but it may help you. It did. You are so innovative.

That's how I've learned. Science was always a struggle for me. It's a tough subject.

It takes a lot of time. So I'm very visual, so I like to use things to help me remember. Okay.

Yeah, and turn it in. turning thing into food always make things more interesting well yeah i like to eat too so i'm a big foodie okay so i know i kind of flew through um blood i only spent about eight minutes on it but that's because i want to spend as much time as i can on bone okay and whatever we don't cover for bone i'll continue recording and post it for y'all okay so there are Two types of bone in the body. Every single bone in your body has both types. So there is compact bone and spongy bone. So if we're talking about the femur, which is the largest bone in the body, we're talking about your skull bones, you're talking about your finger bones.

All of the bones in your body have both compact and spongy. How they're arranged will be a little different depending on the bone shape because a long bone is a lot different shape than maybe your skull bones. Okay, compact bone is the bone that we are going to concentrate on. Compact bone is made out of units called osteons. These are repetitive or repeating circular units.

So compact bone is going to be made up of osteons. So they're just repetitive circle units. Ostions are going to have some very specific things.

Every ostion will have a central canal. This is an area where blood vessels and nerves are going to be found. Does anyone know the fancy name for central canal? The Haversian Canal?

Which one's easier to spell? Central. Central Canal.

You can use Central, but her version is the technical name. I am fine with Central Canal though. So you said it has a Central Canal which contains what? Blood vessels and nerves. Thank you.

Okay. Around every Central Canal, and one day I'll figure out how to change colors on my pen. I think I know how, but it's just going to be clumsy. Around every central canal, we are going to have layers or rings.

These layers and rings are known as lamellae. That's plural. Singular would be without the e.

So when I look at this particular picture I drew, I have one lamella, three lamella. So they're just layers. You can have ten lamella.

I'm just drawing it straight forward. This kind of reminds me of a tree. Don't steal my thunder.

Oh sorry. Tree stump. It is.

That's exactly what people use. But I have some other ones that are food, so y'all know I'm going to show you the food. I know.

Okay. Food and the tree stump. So Bone is very similar to cartilage in that it's going to have those little pits on it. What are those little pits called? Lacunae.

Lacunae. So bone is going to have lacunae all over the lamella. So I'm not going to draw it everywhere, but if you look at a picture or you're drawing your own, you can do it.

So bone is going to have the lacunae. They're just little pits. But since we're talking about bone, it's not chondrocytes. What is it now?

What sits inside of a lacunae now? Osteocytes. Chondrocytes.

Osteocytes. Why osteo? Osteo is bone. Osteo means bone.

Bone. So it's the same concept. Chondrocytes sit in lacunae for cartilage. Cartilage. Osteocytes sit in lacunae for bone.

Same concept, just different tissue. Gotcha. Like visceral, pleural, and visceral, parietal, visceral, pericardial.

Yeah, it's basically understanding that some of the functions are the same, just the naming changes. Yeah. Now, osteocytes are living.

Bone is very vascular. If you've ever broken a bone, it does bleed. Bone is very vascular. which means we can get blood.

to the osteocytes and that's going to bring nutrients and we can take away from the osteocytes, which means that's going to take away waste. So off of the lacuna, you're going to have these little bitty canals. They almost look like eyelashes. And these little canals are called canaliculis, which is just tiny canal. These tiny canals are going to bring nutrients to the cells and take waste away.

So blood vessels go through these tiny, tiny canals. So osteons have that central canal. They have rings called lamella. They have lacunae.

And in those pits, we find osteocytes, and those cells are living, so we need to make sure we get nutrients to them and waste away from them. And that's going to happen through those tiny canals called canaliculis. Now, compact bone are these very neat circular units called osteons. Spongy bone does not have osteons. instead the word spongy I want you to think about a kitchen sponge it's very porous lots of little columns absorbing spongy bone is gonna be made up of units called trabeculae trabeculae are these columns so each of these little columns, that's a trabeculae.

And do y'all see all these holes in the trabeculae? Right here, right here, here. These holes are going to be filled with red bone marrow.

What loose connective tissue fills red bone marrow? looks like cherry blossoms. Reticular.

You got it. Sorry, can you repeat like the last five seconds from made of columns of trabeculae? Yeah, so spongy bone lacks osteons and it's made up of columns, bony columns called trabeculae, and all those holes that you see between the columns is going to be filled with red bone marrow.

Okay, thank you. And red bone marrow is supported by reticular. Okay.

Now, I want to make a very important point here. Trabeculae spongy bone lacks osteons. That doesn't mean it doesn't have the same parts, though.

They're just not organized in a circular unit. It still has lamella. It still has lacunae. It still has osteocytes. And it still has canaliculis.

It has all of the same parts except for what in the center? Osteons. Central canal.

It has no central canal. And that is because... Trabeculae are not always going to be circular.

They may be oblong. They may be almost linear. So they're just not repetitive circular units.

They're gonna be whatever the shape is of the column. So if it's real long and skinny, if it's really large and oval, it just depends. So spongy bone and compact bone.

have a lot of the same parts. Okay, so here is spongy in this picture, here is compact. Okay, does compact bone have an osteon?

Yes. Does spongy bone? No.

Does compact bone have trabeculae? Yes. No. No.

No. No. No. Whoa, sorry. Does spongy bone have trabeculae?

Yes. Does compact bone have lamella? Yes.

Does spongy bone have lamella? Yes. Do they both have canaliculis?

Yes. Do they both have lacunae? Yes. Do they both have osteocytes? No.

Oh yeah, they do. So they have to because they're living and that's going to maintain them. So here is spongy bone.

It has osteocytes keeping it alive. And then here is my beautiful pictures of compact bone. They have osteocytes in them. So both have osteocytes. So if it's bone, it has to have those cells maintaining it.

So the only difference between spongy and compact is basically the shape of it and how it is built in the sense that compact is repetitive circular units. So here's one osteon, here's an osteon, here's an osteon. So they're just repetitive circular units. And spongy bone lacks those. Instead, they have these columns called trabeculae.

Okay. Now, you only have to recognize compact bone under the microscope. You are not learning spongy bone.

Do y'all see these circular units here? Yes. Okay.

They're not perfect. These are bone. Okay.

Do y'all see how some of these units are kind of like weird shaped? Yes. Okay. That's because your bone.

remodels itself every six months. So some of these osteons are older and they're being removed. So like this particular osteon is being broken down. Fascinating. Now your whole bone doesn't get remodeled in six months.

Parts of it does. So like you have basically every few months, parts of your bone are brand new. Now this is just one.

big osteon blown up. What are these areas in the middle of each osteon? The central canal.

Good job. What's the fancy name for it? Aphasia canal.

I don't know how to pronounce it. Aversion. Yep. Okay.

Now, do y'all see these darker spots here? Yes. Okay. Those are the little pits.

What do we call those little pits? Lacuna, lacunae. Both pronunciations are correct.

Lacuna is singular, lacunae is plural, so don't stress about that. Now, what cell would sit in that pit? Osteocyte.

So this is a little different because in cartilage you could really see the chondrocyte. In this you can't really see it, so you have to pay attention to the questions. If I say identify the pit, I am looking for the osteocytes. Lacunae. Lacunae.

Lacunae. Oh. Because the pit is the little area it sits in. But if I say identify the cell, the cell would be osteocytes.

Oh, okay. Okay. So if I say the pit, it's lacunae. If I say the cell, you're identifying osteocytes. Because there's no way to...

differentiate them in the picture. Okay, now you can see the lamella because you can kind of see the layers. They're not perfect, but you can see the layers here.

It's almost impossible for me to ask you the layers on these because I would have to give you a very long definition of what the pointer's on, which gives you the answer. So... We also have models that I'm about to show you.

We use a model for some of the stuff. It's easier to see the lamella and the canaliculis on a model. Now, before I go to that model, these are things that I think looks like it.

So everyone already said this one. What is this one? The oyster. Trace don't. Trace don't.

Okay. Does anyone remember this yummy stuff? Absolutely.

Okay. And this is going to show my fun side of me. Does anyone know what that is?

Lacunae. It looks like cake pans. Okay that is the best answer that you could give me.

Have anyone stacked up dog bowls? Very close. This is a collapsible shot glass.

Wow. However, dog bowls works, cake pans work. So if you google collapsible shot glasses you'll see them.

That's what it reminds me of. So these are just different ways for y'all to think of it. This is from our lab.

You can see we got our central canal right here. This is just one very enlarged osteon. What is this pit right here that I'm circling? And then what is the cell in the pit? Osteocyte.

Do y'all see this little cracks all here yes what are those cracks good job okay now i think it's really hard for me to put a pointer on the cracks without having to like give you again the whole definition so we have models so this is the top view of the model can you see how this is all circular each of these is what a single what Lamella? Well, they do have lamella, but what is the whole unit? Compact bone. It is compact bone, but what is each of this unit called? Osteon.

Can I get the osteon? Yeah. Osteon. Okay. So, y'all were saying things that were correct, but the whole unit is an osteon.

Okay. Now, do y'all see how on this it's showing you the layers of the osteon? This one's just showing you more. What are those layers called? La Melle.

La Melle. Yeah, that's it. And so you see how it's kind of easier to see certain things in the model. Now you can see all these little pits. What are those pits?

And then do you see in this particular one over here they're filling the lacunae in with little brown dots. What are those cells? Osteocytes.

You got it. And then what is in the center right here of each osteon? Haversian canal. You got it.

Okay. And then here's a side view. Y'all see each of these layers? Yep. Okay.

So each of these is, these kind of, we call these the ant mounds. Each of these is one osteon and they're just pulling them up to show you the layers. What are those layers called?

Lamella. You got it. Okay, so I just wanted y'all to see that it's sometimes easier to see this on models than to always have to look on a microscope. That's all you need to know on the models is just being able to say lamella, canaliculis, osteon.

And I have these models in the exercise three notes and activities that you can practice on. OK, so we have three minutes left. I'm going to use our three minutes.

We have a few questions. I want you to throw the answers in the chat. OK, first question I lied. We only have one question. okay okay so everyone that's put their answer in scott correct the answer is d bone and cartilage okay so we have successfully covered all of your tissues.

I'm going to do a real quick zoom to the beginning. Almost there. Okay.

We covered three loose areolar adipose reticular, three dense, dense regular, dense irregular, elastic connective tissue, three cartilages. piling cartilage, elastic cartilage, fibrocartilage, two types of bone, compact and spongy. Under the microscope, you only identify compact.

And we only covered one type of liquid, which was blood. Okay, so this is part of your test tomorrow. Okay, I'm going to stop recording, and then I'm going to open up for questions.

Let me stop this recording.

Transcript for:Connective Tissues: Types and Characteristics

Transcript for:
Connective Tissues: Types and Characteristics