LECTURE: Introduction to Epithelial & Connective Tissues

all right so we begin our discussion here which issues any lingering questions from Chapter three with I know there's probably lots of questions for mitosis and protein sentences but we did cover you know all the required material in the last lecture so let me know if you have any last minute questions or anything otherwise we'll start here okay beautiful all right four main categories here of tissue epithelial muscle nervous and connective in no particular order of course in some textbooks or some other schools even consider a fifth category liquid tissue in this textbook we consider liquid tissues which is blood and lymph to be in this category of connective so if you've seen that are taking the course before and you knew of a liquid tissue category just know that in here we consider it part of connective but what you'll notice this slot is actually great as an introductory slide epithelium and you'll what you'll notice is it's all cells whereas connective is cells living in a background matrix which is pretty much water and some proteins with some fibers so now when you take that to lab if you're looking at a slide and you're wondering is this epithelial connective well ask yourself am I seeing just cells only cells and that's the giveaway for epithelium the one big exception to that would be if you're looking at fat because fat cells tend to just basically just be fat cells with a little bit of matrix in between them but that's a small exception but everyone has seen fat and lab adipose tissue kind of speaks for itself right nothing else looks like it GEB question yeah and proteins and fibers so make it easy epithelium one thing cells as far as when you look at it microscopically right cells only when you look at connective you're looking at cells living in a matrix with fibers so three things cells matrix and fibers is connective nerve tissue will be very unique because these neurons have a unique shape and we're really going to cover more of that when we get to the nervous system don't let this be a very large portion of your brain right now nerves it's own world later on we're not covering that in any depth right now so if you see a brain or a spinal cord laying on the table and we're asking you what kind of tissue just it's just nerve that's all make it that easy okay for muscle there's three types of muscle skeletal smooth and cardiac where would you find skeletal muscle on the skeleton Amen right the spine the sternum the ribs arms and legs all the bones yes brain and spinal cord for nerve skeletal muscle found skull spine sternal ribs arms legs basically all the skeleton what about smooth muscle in the organs the hollow organs making the wall the organs so I've got listed on that study guide that we'll look at a little bit later you can find smooth muscle in the wall of the digestive tract right you can find smooth muscle in the wall the reproductive tract as in the uterus such like that the walls of the blood vessels the walls of the bronchioles right urinary tract for the bladder and their readers so all this is listed on a study guide so if you're if you're asked what type of muscle is found here and you're looking at some kind of organ or organ system it's got to be smooth if you're looking about if you're looking at the skeleton right it's got to be skeletal muscle if you're looking at the heart what is it cardiac so these are very very easy these bottom two muscle and nerve you can learn that five ten minutes no delts right this is where the work is specifically here connective epidemic t'v is where you're going to be spending a lot of times it's a very diverse group okay so what I can offer you in this chapter are really just some hints some a little bit of guidance a little push in the right direction but really this is the kind of chapter now that's all in your lap there's only so many ways or so many times I can tell you you know simple squamous is found just lining the air sacs of lungs how many times do I need to say that you know maybe once or twice it's up to you guys to actually sit down and you know commit that to your learning so this kind of chapter is more so just you it's not me explaining or teaching you tissues it's you spending time enough time that you understood all these we've got about twenty-one tissues to learn okay so I can give you some hints on how to discern one tissue from the next but it's really up to you learn them all right I can't force them into your head so this this chapter is very very very very transparent what do you need to know you need to know where the tissues are found that's it and they're basic functions okay that'll be to tell you right up front for labs a little bit different what's the extra responsibilities and lab not only the functional location but what it looks like right as in a picture or a microscopic image right so that's going to be an in ladder no pictures on this test here in lecture alright we'll start with our first tissue epithelium straight up epithelium you should know is a lining it lines cavities surfaces of organs and skin the skin is going to be the only outside layer as a matter of fact anytime there is an entrance or exit to the body you would expect to find epithelium there as rule right so you think of all the entrances and exits to the body it's not that many of them they're all epithelium right why because the function of of them is to protect its first line of defense it truthfully it is when you study the immune system the skin is known as first line of defense nonspecific immunity because it offers a nonspecific layer it blocks out what it can write it's not specific on what it blocks out just whatever it can depending on the health of your skin if you've got open cracks right is that a very good protection no then it's an opportunity to excite for bacteria to come in so should you ever pick a scab or pop a pimple even ever hell we all have because it's just so so much fun you know what can we say we have nothing else to do and there you go but what does it do it gives an entry site for an opportunistic bacteria which only makes the situation worse because now we've introduced it into the bloodstream notice epithelium does not have a blood supply it's what's considered a vascular so scratching your skin no big deal still barrier is is still there but once we go deep enough right where we damage the skin go underneath the epidermis that's where the blood vessels are in the next layer which in this case would be the dermis and underneath the epidermis so that the rule here is first line up first man or woman on the front is epithelium underneath epithelium is always connected so if I take my skin for example with a piece of my skin most of what I'm pulling here the thickness of the skin is all dermis it's all connected only the very very top surface about the width of a penny is epithelium but it's about 30 layers of epithelial cells or dead cells most of them but most of it is all connective underneath of the supportive tissue right so on the top is epithelium for protection underneath the support connective underneath that is what what's if I pull the skin off what's underneath it muscle so here's the ruled epithelial connective muscle I mean somewhere in there you're going to have nerves coming up infiltrating right but the nerves go all the way through somewhat into the epithelial layer but the blood vessels stay in the connective layer so that's just an overview I'm going to repeat all this stuff as we go to the chapter that gives you a nice perspective of how the tissues are layered but the four main functions here of epithelium is what line protect secrete absorb that's what you need to know line protect secrete absorb then some extra information included on the slide will be is that it can have a sensory input and epithelium makes up glands so if you're looking at a gland in your ass what type of tissue it is its epithelium right so how do we live it do glands secrete substances to the outside of the body yes right anything to do with secreting absorbing or anything that surface of the body the environment around is going to be all epithelium okay all right so here's the other characteristics we were talking about it is a vascular which means no blood supply but is innervated which means it does have a nerve supply so if you want to translate this looks Wow hold on a second I want to translate that statement go ahead and over here and you in the side of the slide go and right no blood supply yes nerve supply or something like that in your own language it has no blood supply but it does have a nerve supply and this last word here this is very very important highly regenerative which means epithelial tissue heals very very well so let's say let's put it in a perspective of a of a question what will be the prognosis of a epithelial tissue injury good or bad good right that means it's there the capability of it healing itself is very very good because it is regenerative whereas cartilage the prognosis is very poor and these things will learn as we go but this cartilage doesn't really heal that well but epithelia does college is a type of connective whereas all epithelium will regenerate quite nicely so let's say every seven days you get a new layer of inside epithelial cells in your digestive tract every week right now how healthy those cells are depending on it depends on how healthy you ate so if you ate McDonald's for a month oh my god who in the world another was that one guy that did it but that's insane I can barely eat it once a month with the exception of the french fries sometimes I can squeeze those and more more often anyway you get the point right your cells represent the health of what you've eaten in the past via you need to have that good lining on the inside because it does protect and it is required to have that good cellular makeup for absorption if you have poor cellular makeup or poor water intake you won't be able to absorb nutrients or even use them properly so there's a lot they could be said about epithelium in the future when we get to A&P - especially for the digestive and urinary tract alright last thing I'll cover on this slide is that we have micro villi or cilia on the apical surface what would you say is the apical surface the top of the bottom the top whereas the basal surface here obviously at the bottom which borders what's this down here in the pink that's our connective and this you know all those just the illustration notice the very very stark difference when you're looking at epithelium you see all cells that's what I was saying before when you look at connective and you can't see so much in this picture it's not a full image but you already see you can already notice that you you're going to not see just cells in connective the cells are going to be very sparse sparsely located all through the connective tissue but there's going to be a whole bunch of matrix which is water and collagen throughout that tissue when you look at epithelium what are you seeing cells that are arranged in somewhat of an orderly manner whereas connective is going to look a whole lot more random in most cases yeah so we'll see cells arranged in one layer which is a simple arrangement or stacked which is a stratified arrangement coming back to this are different shapes squamous cuboidal columnar I've got them on the board if you can see it the flat cell squamous the cube shaped cuboidal and the column shaped columnar aren't they named pretty appropriately which of these if you can see that on the board which of these can hold the most water to clung ourselves you would expect that to be in the the digestive tract and the respiratory tract because we need mucus don't we in both of those areas does it make sense so a lot of the design in the structure of the cells goes along with the function what about which cells the smallest which one can fit in the tightest spaces squamous cell so you would expect that to be found lining small places like the inside of the heart lining the blood vessels the inside wall the blood vessels right is pretty small yep and the inside air sacs of the lungs so when you're talking about small tight spaces your best guess is a squamous cell right when you talk about large spaces that require a lot of water to be around its columnar cuboidal is a very unique set of cells found in glands so we'll see that coming up so we take these cells by shape mix them with the layers the choice of layers simple stratified or pseudo stratified and that's how we name the epithelia so a simple squamous epithelium would be one single line of squamous cells right like we saw in this picture here at the top simple squamous and that'll be it should be pretty noticeable right because you're just seeing cells that are lined up if you take stratified squamous it be stacks of squamous cells how about simple columnar it should be a single row of column shaped cells right pretty orderly actually pseudo stratified is tricky it means falsely stratified this indicates really more of a simple layer but every now and then looking stratified so it's kind of messy it looks like a simple layer of Columba ourselves that's been kind of squeezed together so now it looks a bit stratified at certain areas so that's why it's called pseudo stratified so we mix all these up and we come up with seven main FTO tissues here at the bottom of the slide we have to know we are responsible for right now in lecture and lab both simple squamous and stratified squamous what do they look like were they there for you know where are they located everybody got that so simple squamous would be a very very small thin layer like the inside of the lungs and saddle blood vessels inside of air sacs as long as I should say stratified squamous would be like our outer layer of skin epidermis and stratified squamous will be located anywhere there's an exit or entrance to the body right what's the what's the value here of having stacks of cells more protection so anytime we enter or exit the body this is what we want is more stacks of cells for protection so the mouth right the anus the vagina would have these type of things right entrance or exits to the body the difference is is that stratified squamous epithelium with no keratin on its apical surface would be those entrance and exits however the skin itself the epidermis would have a keratin on its apical surface keratin protein spill delts so you would call it keratinized stratified squamous epithelium so if you if you don't know these simple terms here on this slide you can get lost when we start adding words keratinized that kind of thing because then we're just being more specific all right everybody go with this and listen you know trust me I know this is it gets to be a lot in this last stretch right before your exam it seems like there's no way you can possibly get all this stuff in but if you have a strategy I promise it's possible as I was telling my last class you know make it a point like today hopefully you're like your Texas today you're out of luck but hopefully you did this in the past make it a point where you say today I'm going to learn empathy not that today I'm learning all of chapter four today I'm gonna learn epithelium make a small useful goal right once you learn it then build on it say then tomorrow I'm going to learn connected then the next day I'm going to learn I'm going review both epithelial and connective so don't start off Bob trying to sit down and learn all these in one sitting that's a horrible strategy unless you've just taken this before and you're reviewing you want to build with small goals like that especially in this comma Tyrael okay so let's get to it simple squamous we're going to fly through these because really everything you need to know is on that handout I've got for you the quick study handout but real fast simple squamous inner lining of blood vessels and heart air sacs of lungs here's an actual slide of it you can see it's not exactly how we saw it right here this is a different cut of it but it is an orderly lining of cells is it not so that's simple squamous do you see any fibers transversing this slide no so it's not connective it's not muscle and it's not nerve just by sight you can see that so kind of maybe sometimes work backwards it's not multiple layers is it so it's not stratified it's not all over the place like transitional or pseudostratified so you're left with a simple arrangement of flat cells are they cloned ourselves nope right so sometimes the easiest way is to work backwards by logic alright stratified squamous two main types keratinized non-keratinized where do we find carrots nice only in the skin the outer layer of the skin the epidermis realize just to get back to our terminology of pulling up the skin again if I pull up the skin what I'm really pulling or pinching is all dermis it's all connective only the top surface that we see is epidermis which is epithelium so in order we said the top surface should be epithelium then connective underneath it then muscle underneath that then the nerves are going to come you know through that all that all that tissue with all three layers the same thing goes for an intestinal tooth if your if your fingers on the inside of an intestinal tube what you're feeling on the inside with the food will be travelling which is called a lumen if you want to know that that first layer is going to be epithelium in this case will be simple columnar then underneath the simple columnar you would have what you just got that picture here's our simple phone arm this is where the food will be traveling right in the middle where it's white this is we call the lumen so with surface itself servers were the Luminess right would you be touching the food right or the mucus the basal service would be at the bottom where it says basement membrane and what type of tissue is beneath the basement membrane connective what type of tissue should be underneath that muscle right and then somewhere in the cross section of this cut you'll see nerve fibers coming through you can't really notice that much they're pretty small but you will be able to see blood vessels on another slide not this one do you see any blood vessels here in the f2 of the cell phone are no blood vessels it's just the cells just cells if we were to expand this picture and we got to see more of the connective underneath the basement membrane you would get to see all the blood vessels that have been cut maybe some of the nerve fibers and some of the other glands and such that are located but yeah we can't see all that in this particular shop but notice I mean I keep going back to this all the valuable stuff isn't in the connective layer the epithelial layer is there for what reason for protection primarily also to be the first to absorb right so everything every nutrient that we absorb through this lumen in this white area where the food's passing through it's got a pasture these cell membranes the apical surface right so the nutrients have to be small enough right to diffuse across that cell membrane then as they come into the epithelium this is more of an A&P 2 topic but it's fun as they get into epithelium where do they have to go now to get in the bloodstream they have to continue to diffuse into the connective right and now what's in the connective the blood vessel so now they have to diffuse from that tissue through the wall of the blood vessel what lines the walls of the blood vessels simple squamous so if you look back to the function of simple squamous tissue it is so study ends with diffusion diffusion right that's the hallmark of simple squamous it's thin enough that you can diffuse right through it right so that's a big story to get those nutrients right in that bloodstream then in the bloodstream how do we get the nutrients around the water it just circulates right then it goes to another cell and now it has to diffuse again through the blood vessel wall into that new cell so that's why we learn so much about transport because it really is though you know the hallmark of communication throughout the body so you're taking something simple like this in Chapter four and now bringing it into chapter twenty three I think is where it is in the digestive system a and B - so that's why you we notice the people that do the best in AP - are the ones that really got it in the whole chapter three chapter four category because this is it really is the standard to understanding the body is these two chapters here so do your best you know it'll help you later okay getting back to the simple layers are are stratified here in this case this is stratified squamous notice all the layers this is going to be keratinized or non-keratinized right it's all for protection either way the difference is the location if it's keratinized its epidermis is NaN carrots and honest these other regions right okay so here all this is what that's your entire the thickness of all these stacked cells is all your epithelium your stratified squamous underneath that basement membrane of course again is connective in this case it's dense irregular if you wanted to jot that down dense irregular will be our dermis that we'll learn in chapter 5 so any blood vessels here in the epithelium nope where the blood vessels down there beneath in the connective area okay great now we can see the characteristics of the shape of these cells is that they're more rounded you could say at the basement membrane as they go up they get flatter it's because as they go up toward the surface they die so they lose their cytoplasm they get flatter yep so these are the new mitotic brand-new fresh cells down here at the bottom right so you'll say okay well if there's no blood supply how long were those cells get their nutrition through diffusion right the nutrients come from the blood vessels down here and pass their nutrients to the cells up here so it's it's quite cool alright cuboidal not much to say about here just a simple layer here of cuboidal shaped cells in the middle here would be as secretion either the urine or the glandular secretion so this is tough to understand in perspective think of what you're seeing here in this picture as a snake-like tube it could be one long tube that's coiled around right and we're taking a good transverse slice of it and we're seeing that same tube being cut in all different you know views here so this could be the same tube where several tubes being cut but what's passing through it is what's in the middle and the white but again this is not simple squamous right because the cells are not necessarily flat they're more a little more bulgy so that makes them cuboidal okay for a simple columnar excuse me location GI tract and fallopian tubes the two main locations these are also called uterine tubes by the way if you see that on the tests uterine tubes or fallopian tubes same thing what does GI mean gastrointestinal so we would find simple on our MD stomach and small and large intestines right in this case that epithelial layer if you want to jot this down the epithelial layer in the GI tract which is columnar can also be called mucosa why because it has mucous it secretes mucus doesn't it so the epithelial layer in the GI tract is simple columnar but it's also called the mucosa if we go underneath that epithelium to the connective layer that will be called the submucosa okay so the submucosa would be connective and the mucosa would be epithelium perfect do you think I might have said that for reason that could be could make a nice little snippet on a test question so what is this I'm kind of setting you up here perfect amen straight a-all right and this down here is the submucosa right because it's beneath the mucosa right putting it all together you'd be surprised how many times you can wiggle out of a test question just by knowing a simple term and I'm telling you that from experience if you take an impossible exam like the MCAT you wouldn't believe how many times you can we wiggle or weasel yourself out of a difficult question just by knowing sometimes one word so that's one of the greatest tips or things I can give you because I sure we're not going to go through all that you're going through again I don't miss those days at all I still I still find it very laughable that I'm a teacher I really do cuz I remember taking the review course for the MCAT and there's that it was a girl that was in medical school teaching the course and she just stand out there just talking for our him he's the review class were like four hours long I just shaking my head you know I already checked out about ten minutes after she started talking it's like how in the world could one person possibly know that much information you know and the only reason why people know that kind of stuff is that when you live in it long enough and it's your only thing you think about your vocabulary what you see and talk and experience every day you just soak it in so this right now it's so painful to your brain possibly right now because you're breaking new ground you're honestly breaking tough ground in your head and you're you know filling it with a bunch of information it gets easier the more you scratch that surface you know inside your brain more you cultivate it learn different things the things start to soak in a whole lot easier so it's my job in a p1 to kind of irritate you push you into uncomfortable territory so that when you get to anp2 you're little bruised right and you can kind of soak in a little bit and have a little bit of healing yep it's quite a journey but so some of my test questions they may not seem fair or the time may not seem fair well on the the soft side of me I'm like oh I'm very sorry about that but the tough for sodomy is like just deal with it because you're about to enter into a field where nothing is predictable right you think you're going to get a patient with symptoms that make complete sense no so obviously you know it is tough but I kind of have a dual job for you like any professor really not just me but yeah we have to make you we have to squeeze all this kind of stuff in your head you know because really truthfully as a nurse you don't need to know tissues you know not unless you're in a lab or something you don't need to know transport or electrons but what all that's doing is stretching your brain right seeing how well you can take in information and manipulate it and then make something you sweater that's what all this is for so I kind of apologize for all this tissue stuff because it is sort of unnecessary in a large sense but very necessary to get your brain moving you know to stretch it a little bit alright so back back here to the tissue this is pseudostratified notice how messy it looks it's not a very simple clean arrangement it's not necessarily stacked cells it's kind of like just squeezed together so what can I say it's long tall cells so you know it's : R it's messy so it's pseudostratified that's my best description I can get you we've got tall cilia so we know we're in the respiratory tract here yeah yeah a chunk of it yes it is this is what it really looks like here with the mucus droplets in here see if you've not taken micro yet you don't have a sense of how this color comes to be it's not really that color you saw a person has stained stained this slot of tissue with some dye and all the proteins take up the color at a different rate so the darker colors mean that there are thicker amounts of protein they're soaking in that die anyway you get to see the cells that are kind of jammed together long tall cilia on top so this the full name of this would be pseudostratified columnar ah ciliated epithelium the acronym is PCC II there's the full name at the bottom law would ask first of all where it's found right I would say what are the long side projections on the apical surface so if you don't know the apical surfaces that question is meaningless right if you don't know what to say the projection is that question is meaningless but these are all terms that we've covered right so they kind of build on each other but mainly the location since I don't have pictures on my test in lecture 4 lab I will just simply show you a picture and ask what is it alright or if you have my lab class you know simple arrow pointing step helium I might say where could you find this tissue some people might jump and say pseudostratified columnar well that's not the answer the question right the question was where is it located you just named the tissue correctly but you answered the wrong question so they'll be wrong so don't do that in lab and everyone does it every semester and I hate to count all for it because you gave me a good answer but that's not the right answer this is found in the respiratory tract yep okay the trachea has point to it right there all right moving on transitional transitional is certainly like everything mixed together we don't have flat cells we don't have columnar or cuboidal cells are all kind of mixed you don't really know what's going on there's no order to it at all so we just call it transitional this will be found lining the readers the bladder and part of the urethra areas that can change shape due to the volume of fluid in those in those areas transitional and then realize it's the inside that's what a lot of people miss we're talking with the inside lining of the bladder the inside lining of the reader tubes right coming from the kidneys to the bladder and the inside of mainly the prostatic urethra the first part of the urethra as you reach the end of the urethra where it exits the body what type of up there and would that be stratified squamous right okay beautiful so this was the epithelium here which is the inside lining what's underneath it connective beautiful we got the trend now because we're about to get into connective underneath this underneath this epithelium underneath the connective excuse me you would find kind of muscle smooth muscle so when you're asked and this is another tip in lab when you're asked if you get this chunk of tissue a picture like this you're asked what type of tissue lines or is lining here the lining is the key right you're talking about what type Peppa thulium is aligning right what type of tissue is supporting in this slide connective what type of muscle is found in the slide if there were in a slide smooth right so be sure you're reading the question and be sure you're looking where the arrow is pointing if my ro is pointing down here underneath the connective where muscle might be and I say okay name the tissue and you see all this up here and you say transitional but the arrow is pointing to the muscle isn't it and the question again you just answer the wrong question so just be careful where the arrow is pointing and what the question is asking you or you know if we don't even ask for location we might ask the function what's the function of the muscle in the bladder what does it do what do muscles do they contract right they squeeze things or they move things right what's the function of the epithelium in this picture line protect secrete absorb what's the function of the connective in this picture support right and that's where you're going to have the blood vessels and nerves right okay all right so the last part of epithelium it's last characteristic is that it makes up glands so we have two types of glands endocrine and exocrine now our job right now is to learn exocrine in a and P to one of the beginning chapters you have well they change the order now I think you don't get it too a little bit later but the endocrine system is all about hormones right these are glands that don't have ducts endocrine glands whereas exocrine glands do have ducts it says it all in the prefix of the or EXO means what it has ability to exit the body endo means it does not exit the body right no one happens to leak out testosterone hopefully hope not right or estrogen or anything like that or thyroid hormone right those all stay in the body don't they those are all endocrine hormones which means they're all hormones have been produced by glands that don't have pathways that lead to the outside the body so everyone knows what a duct is like an air conditioning duct you know it's a channel for air to pass through well exocrine glands have ducts right so it's prati gland right here everybody squeeze their teeth together you can feel that muscle on the side of your cheek right on top of that muscle is your parotid glands a salivary gland the glands over here but being a salivary gland it has a duct or passageway that empties the saliva into your mouth right so that's what I mean by a duct it's a channel so they secrete there's certain other products onto the surfaces of the skin or in a cavity in this case would be the oral cavity what's another kind of gland like a sweat gland or an oil gland to those reach the surface of the skin yes they're all exocrine okay so one unicellular type we have is the goblet cell it's a big old mucus gland that will look at real fast the other multicellular ones are the ones that will see the different shapes of this is our big old goblet cell all the mucus droplets here in these secretory vesicles where these secretory vesicles come from anybody can answer that what's the packager the manager the cell the Golgi right there you go okay and they're going to find their way out of the cell through what process exocytosis right excellent don't you miss those good old days cell this was mucus here on the bottom unis say their gland that produces mucus the goblet cell why is it called a goblet cell yes it looks like a goblet right that's a wine drinking fellows back then all right here's some idea of the different shapes of glands now listen I'm not interested in you guys knowing all these shapes if this was a histology class you'd have to know every single shape but fortunately this is a and P right so I just want you to a few of them I'd like you to know the this one right here for salivary glands compound to below alveolar and sebaceous glands right here the simple branch novel ER and that just gives you a good experience of kind of knowing what these words can mean compound means multiple channels off that one single channel simple means what one single channel leading to branched Sachs so the alveolar means sex or a sac shape like a clover shape whereas two below alveolar means what some of them are tube shaped at the bottom and some of them are rounded like a sack and compound means it has more than one channel compared to the one in letter D so just knows those two D and G as an example but notice in the yellow this is what you really have to notice obviously in the yellow is the epithelium right which is what kind of F through seems like stratified squamous but it's actually simple cuboidal cube-shaped cells maybe you can't see it it's kind of small simple cuboidal cube shaped cells that actually dive into the dermis in this case and then dive come up right back out to the surface so the epithelium itself is simple cuboidal but it's the gland itself is found and we're in the connective tissue what's kind of confusing the gland is made of epithelium but the gland is located in the connective layer it's kind of pushed down in there so notice that but all of its products will be secreted where upward toward the surface of skin okay okay so two types of classification here functionally merocrine whole Crenn and then we'll move on to connective tissues think about this do you want to secrete just parts of your product or all of your product at one time in the case of an oil gland a sebaceous gland right it secretes the whole amount of product at one time the whole amount means it's a whole occuring secretion if you're doing a controlled amount of exocytosis a little blip here a little blip there of mucus coming out right it's controlled that's called merocrine so that's the two ways to know those so anytime you see a sebaceous gland it is holocrine other glands are merocrine in their function so here's the small droplets of mucus coming out controlled or the whole thing explodes and pushes out all the oil in a hole in secretion okay and that does it for glance just a trip a quick trip down that when we get to our skin chapter will learn the difference in the different sweat glands but otherwise that's it four glands right there all right so we're moving into connective tissue any questions about epithelium we're halfway there guys okay muscle and nerve is not that much to learn at all connective is a big a big stretch of we got ten tissues to learn but some of them they're quite easy something like blood very very easy right bone very very easy fat very very easy so really take those three away now you've only got seven right you can manage seven tissues and even some of those seven are quite easy so you're ready to go down them down the road wait let's list would we rather a nap with some hot chocolate and cookies or what or learn connective tissue or how about this let's just get the a and keep moving right there you go I hear you I stand up here and talk all this time believe me I know it's hard to harden number one it's hard to care about anything I'm spitting I know it is trust me I was a student for a long time it's hard to keep focus it's hard to care it's hard to you know keep one and keep pushing yourself to learn this stuff but still I have a job too to keep talking to you so I have to just pretend that you're learning but really truly it's just about exposure you know you're exposed to it here in lecture you're supposed to go home and review these notes make opinions on on those notes yourself ask questions write down questions go see the tutors talk to your friends about it that's the whole process um there's no way you can just learn in class you're kidding yourself if you think that you're ever just going to get it just from lecture most the things I've ever learned in my life I never ever ever got from a professor because they basically either didn't make sense or where they couldn't speak the language honestly like my physics professors never spoke English it seems so yeah I remember all those days I'm not understanding a word and plus it had powerpoints back then you know we have messy chalkboards in college and they were enormous my Ole Miss days in college was an auditorium with flight sometimes close to 200 people I was way you know in the back possibly a little chalkboard up here with a short professor hunting like this writing on the board so at least you guys have things like Google and digital stuff you know digital knows all right okay so connective is all about binding and support right it does offer some insulation it still offers somewhat protection because it's a thicker tissue it has a matrix right so what we said about connected before is connective tissue is cells different kinds of cells right will have different names now we're not talking squamous cuboidal columnar we're talking things like fibroblasts or chondrocytes right or osteocytes so a whole different family of cells that we have to learn now depending on the tissue so we always have cells living in a matrix that matrix is going to be mainly water with some proteins and other neutrik nutritive factors in there and fibers so cells matrix and fibers those are your three four connective tissue the fibers are going to be collagen which is a thicker supportive band of protein of course and then elastin which is a thinner band which gives you the elasticity the snapback of your skin and then another fiber call reticular which is mainly just in the lymph organs and bone marrow so three three type three characteristic cells matrix fibers right the cells are going to be varied depending on the tissue we'll put an to certain tissue fibers or certain tissue cells I'm sorry then we have matrix was mainly just all water with some proteins in there and then these fibers which is collagen elastin in reticular so that's we're going to see it is the most abundant tissue all across the body because it's between everything right in between all the organs if it's not epithelial and it's not muscle it's all connected basically so it's a big old range of tissue here all around the body it is derived from bezençon so anyone in here that's ever had any experience with you know body work like massage therapy or even occupational therapy or physical therapy all these tissues right bone cartilage everything in between all the other filler tissues all came from the same route embryological tissue called mesenchyme so that's why in the body work world especially like in chiropractic we can do things in treatment wise that makes sense they're not just who do voodoo things I can press on a trigger point in the PEC and make a sore throat go away right or hit a certain trigger point in the neck and help TMJ go away you know these kind of things are not just accidental it's because they're you're basically tapping into a root system of tissue that's been established ever since the body's been around it's not like we made it up we just discovered it I guess people in the past but yeah it's very interesting you can do a lot of work just with the body with respect to messing cotton because it's all came from the same root tissue which is this embryonic stem cell tissue so what I'm saying is in the early days when you're being formed this generalized tissue mesenchyme gave rise to many many different types of cells right many many different types of tissue okay it is usually vascular which means it has what good blood supply usually good nerve supply right so it has good innervation good vascularization the exception on both of these is cartridge cartilage is very poorly liked no blood vessels and no nerve supply so what is the prognosis of cartilage healing not good very very poor right so you damage your cartilage you damage discs in your spine you damage a meniscus in your knee you damage the labrum with a connective tissue the cartilage in your shoulder those kind of things can keep you out for a season or for your whole career right if you're in sports they don't heal very well all they do heal but never to the point where it's back to where you were prior to the injury never it's always there's always some deficit there depending on how much therapy you've had how much nutrition you're able to offer you increase the prognosis but you never can get back to pre injury status in that case cartilage is not good to be injured so again we have cells living in a nonliving matrix so here we go this is embryonic tissue this is bezençon the very generalized tissue that we all are made of until things start differentiating right into other tissues that we have as an adult so this where we all come from tissue wise so these mesenchymal cells can give rise to other types of cells in the future and that's why they do so much or try to do so much with stem cell research they try to take a stem cell on mesenchymal cell and try to guide it to become a nerve cell or God it's become a new muscle cell right because they want to try to deal some diseases that go or prevent diseases so here's our different cells fibro as going to be your generalized connective tissue cell chondros for cartilage osteo for bone hematopoietic for blood and a Depot for fat so do know all of these cells so the prefix is important because it tells you the region of the body right so Cointreau is automatically what region cartilage osteo is automatically what region bone hematopoietic automatically something to do with blood right hematopoietic stem cells can become red white or platelets red cells white cells or platelets adipose always fat so the prefix tells you the region the suffix the end of the word tells you more sort of the function of what it's doing a blast means something that's forming so a konso blast is doing what to cartilage forming cartilage right a site is more of a mature cell maintaining a tissue so an osteocyte is doing what maintaining bone tissue whereas nasty oblast would be building bone tissue on osteoclast in this case would be something that actually breaks down bone tissues but in it for a reason it breaks it down to suck the calcium out of it because if we're not eating dietary calcium we call upon these osteoclasts to steal calcium from our bones to put in the bloodstream why do we need calcium the bloodstream to make our muscles work like the heart that become important right so yeah the bone we'll see in the chapter coming up in chapter 6 is just really a bank of calcium that the body uses to steal from sometimes if we're not eating eating enough calcium and of course as we get older that turns into a big hormonal problem it's hormonal ii driven so some women and some men mostly women though lose their calcium in their bones because of this hormonal disorder controlling the osteoclast so we'll see more about that later for right now just know the cell types and know what these mean but everybody get them site is a maintaining type of cell a blast as a building cell and a class is a destroying cell yep sites anything with a site is just amateur cell amateur cell maintaining the tissue a blast is a forming or building self building a tissue you could say and the class is a destroying or resorbing you can put that way resorbing cell alright so that sets the stage learning and tissues really the last thing we'll do before we get to them is just learning about the matrix so remember we said cells matrix and fiber we did the cells just now now we're doing matrix the matrix is fluid which is what water right proteins general proteins which are always made by these cells and proteoglycans which are proteins with sugars attached the fibers like we said collagen elastin reticular the tougher fiber the collagen is the one that gives anyone's tissue or if you want to look at skin as an example the underneath the connective tissue here gives you the tone so the ability to you know manipulate the tissue and it it holds itself very well has a tone to it as a form to it is due to collagen if you see someone with their face completely droop down where the skin does not tone up itself and hold itself up they lost their collagen right so what do people get injections to pull it up right or something like that the snapback stretching not just the stretching but it's also the return to the original shape is the elastin fiber so good healthy amount of both of these gives you you know the healthy skin that we all want to have so what's the best way to encourage these fibers sticking around good water is motion right would you say drink water drink woot li drink water you're right that is the number one reason bingo you got it right there without water there's no chance of you maintaining these proteins right because they denature like we talked about but to maintain them otherwise physically is through motion so that's why I massage is one of the best things you can do I'll run body certainly you know not that we go around massaging our face but we should at least like in a shower rub your face like you know some hot water or something keep it keep it active slap yourself around a little bit you wouldn't believe all the things I do I'm a weird cat man yeah she does she's tough man oh my goodness he there is no doubt if someone asked me could your wife kick your butt I would clearly say yes she is that strong it's not like I'm a wimp but she is like got some kind of genetic I don't know what she is damn strong man you can't I her bus alone would is inhuman she doesn't look crazy but she's really really strong fast reflexes we try to spar every now and then just for fun you know it she's fast anyway okay um so yeah our three five is a tough one collagen elastin for stretching reticular is branching that forms a network in our lymph organs we'll see that probably more so in anp2 so here we go our first tissue areolar or a real ER however you want to say it it has several names this is one of the names areolar connective another name is connect tissue proper and another name is loose areolar connective so it has three different names just you know or you just call it loose areolar what can you say it is the very generalized tissue that's around the entire body found between organs so and it's one of the easiest to identify because it is so generalized here we go notice we have cells right sparsely located it's what I was saying before these are our fibroblasts these cells what do we say the connective tissue was cells living in a matrix with fibers right the matrix is the background fluid we see what you're really seeing is the white light coming from the microscope through but that lets you know that there's a matrix there because it's just water and you see the fibers the thick bands of pink here would be the collagen the smaller black ones would be the elastic fibers right there's still all proteins either way this is loose areolar this is your generalized connect tissue found between all the organs it packages the organs right surrounds capillaries it's found in all cons and looks and crannies really it's also found in the dermis along with the denser regular that we'll see so many times it's really a better way to say is where is loo so real or not you know it's it can find its way almost everywhere it's it's kind of mixed in quite a bit if you look at a steak and you see all that marbling on a steak or the underneath of like some chicken skin you know you pull the skin off underneath it that's all looser really all the stuff that covers organs is loose really adipose has an extra function but ah besides being protective and supportive it is known to give energy right it's tissue is unlike any other we do have some matrix right but in a lot of slides for adipose all you see is just fat cells don't you like the one in lab I think was just a bunch of white cells like this what are they carrying these white cells fat so to stand water mix so these cells water is usually an intracellular fluid isn't it but these cells have fat so fat and water can exist in the same compartment really so the more fat cells you have overall like if you have an increased level of fat in your body overall that means the less water you can hold as a person so you tend to be more prone to you know dehydration just from having more fat cells because they can't hold work the water is between the fat cells so in a sense you could hold water like that by bloat but who wants bloat bloat is not useful water useful water is water inside the cell in fat cells just don't have that but we still need fat for energy of course no doubt and insulation you can see the nuclei kind of pushed to the outside of the cell here they call that a signet ring appearance anybody know what a signet ring is in the old days guys used to give promise rings to a girl could be into that these days would it mean anything forgot a promise his loyalty that's terrible isn't it what a guy's had to be such jerks oh no why do women have to be so confusing I better not say that actually women are very simple they want respect absolutely unconditional love and great hugs and the ability to say I'm sorry whenever right I know what you're sorry know exactly why you're sorry Andy and to really mean it not just to say it right that's hard to do for some guys it really is that's a challenge because sometimes we just are mad and we don't want to be sorry that says usually help anything though it's best just say honey I'm an ass and I'm sorry that usually works anyway okay we taking the tissue many reticular fibers this is the one out of all the connective tissues that you probably need to know the least about I would just kind of save this one for a and p2 to know that it's found in your bone marrow and lymph organs but reticular we don't even have in lab I don't think we even covered that in lab so it is part of the loose category loose category is a real er adipose and reticular right so this is the last of the loose category loose means we see fibers and cells loosely arranged that's what that means right so that's all for dense dense compared to loose right single point what we notice in the dense picture you don't see much matrix to you it's there but it's just more fibers than anything else it's very dense loose means you're going to see some some matrix in there loosely arranged among cells dense means is very packed with fibers so in this case it's dense regular which means a regular uniform orientation of the fibers a very predictable orientation and this is our tendons and ligaments this is what we would expect to see in an MRI right it's a nice good even arrangement or if you had a rip in this tissue of a tendon or ligament it wouldn't look so even we'd see scar tissue easily in this be very noticeable that it's not uniform if you look at a non-uniform denser dense tissue this would be it so this if you notice dense irregular is like taking dense regular and kind of swirling it up right mixing it all up that's why it's called dense irregular it's dense but it's what a regular non-uniform alignment of the fibers which has a purpose the regular alignment means that if you take fibers like this a regular alignment means that it's tough it can take some tensile strength to it right irregular arrangement is useful in what way it can withstand torsion right this cannot withstand torsion it breaks apart but dense irregular can withstand torsion so that's why we're convinced regular for tendons and ligaments for more more of a 1 1 plane motion where a dense irregular is useful where there's lots of different kinds of motion and different kinds of stretches stresses I should say so again dense regular is found on tens and ligaments and dense irregular is found of course in the dermis also in the submucosa if you want to write that down but organ capsules is a big one for dense irregular it surrounds these the joint capsule here so it's just a tougher it really is a tougher type of connective tissue and this is the one that is not really given that much attention in the book I wish it did but this is the one that's usually found all the examples when I showed you where connective was underneath the epithelium like in the bladder and the skin and the intestines all that kind of stuff all that connective tissue was dense irregular right okay and a lot of times dense irregular is going to be mixed in with loose areolar and there could be even some fat somewhere right fat can go anywhere really so they do tend to mix but what do you clearly see if we go back in time to the beginning of the class could this ever possibly be epithelium you see the stark difference now epithelium is all cells right plus there's no uniform alignment here there's no stacks there's no single layers right there's no column shaped cells we see fibers swirled up all together so we know it's automatically connected and even muscle will look different than this because some people could argue that looks like muscle muscle has more order to it a predictable order than this would alright so getting into the cartilage so if you've got a strategy going for connective this is actually my strategy but I'm hopefully you know encouraging you to use it you got your three loose because we got ten to learn you can take your strategy and it's right on that handout I've showed you earlier you've got three loose to dance so how many is that that's already half of what we need to know and that's not that bad right having a strategy like that now we're going to three cartilages so how many we have left to bone and blood which are very very very easy to see okay so having a strategy makes it more you know workable in your head the three cartilages are pretty much pretty unique themselves hilum is clearly the most abundant found all over the body run around the ends of bones so that where it says articular cartilage this is clearly the end of the bone whether it be the end of the rib the end of the humerus into the ulna the end of the finger bones it doesn't matter every end of the bone is called or is lined with I should say articular cartilage articular means joint so it's joint cartilage when people say that Arthur came to town or they have arthritis this what they're talking about hyaline cartilage has thinned they've lost the cartilage somehow either through injury or just non use they just get old or something it got thin that's what we're talkin hyaline cartilage is the cause of for the loss of hyaline cartilage i should say is the cause of osteoarthritis so we'll see that in the bone chapter but this is our regular articular cartilage is what it's called generally speaking also found the trachea it's the most abundant here is the cells what do they called its cartilage now right chondrocyte cells living in a matrix right the matrix is a very thick protein dense water matrix so Highland crawl is pretty unique and that's a very smooth looking you know kind of relaxing looking Cartledge you're going to put it that way it's like looking at art you would have a different of course description than me but either way it's pretty easily noticeable compared to elastic look at that very stressful right intense looking all this intense these fibers that you see are the elastic fibers that have been stained to stick out so that's a big difference from that isn't it so Highland College is this simple squamous no is it fat nope is it loose areolar once you see these enough you can work backwards and figure out what they're not and sometimes it helps you figure out what it is so the elastic fibers give that one away big apparent cells however give cartilage away in general our last cartilage is fibro found all throughout the disks the knee to disks in the spine even a little disk in the jaw that gives some people trouble if they clinch their teeth at night it is our strongest cartilage which means it has a very very very very dense matrix even denser than hollow that gives it its strength again sparse cells all located through the matrix could this ever be stratified squamous or simple columnar or transitional right that's how you know you got it if you can realize that the big differences here it's not bone it's not blood it's not fat right so know all these categories and you can tend to work through it very easily real quick on bone where is bone found in the bones there you go it looks like the rim of a tree can't miss that no other tissue looks like it blood contains red cells white cells the big ones platelets and little fragments the matrix is what e plasma water again blood looks like no other tissue easy to notice and there's your review know that slot really well and you should be fine alright guys so good luck on your lab today if you've got it we'll finish this off Thursday and then start chapter 5 of course your test is a week from today

Channel: Dr. Michael Sliman

Views: 1,066,337

Rating: 4.8039269 out of 5

Keywords: connective tissue, anatomy and physiology tissues, Epithelium (Anatomical Structure), tissue review, A&P epithelial, A&P Connective, Tissue Study Guide

Id: hIhD0azoFBI

Length: 73min 38sec (4418 seconds)

Published: Tue Feb 24 2015