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BIOL 2301 Human Anatomy & Physiology I - 2301_lecture07_0913
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00:07 So here we are, the Tuesday our first exam. No 1's excited
00:13 that. That's no big deal. just an exam. Um Just a
00:17 of things. First off, your extra credit is gonna become available.
00:22 there's extra credit. Yes, I there was on the first day.
00:24 right, so this is how the credit works. Make sure you write
00:27 down because there are no extensions on credit. Alright, tomorrow tomorrow's what
00:33 , Wednesday, Wednesday thursday is the . So this is true for every
00:38 exam, the day before the exam six p.m. A link will open up
00:44 blackboard and you'll have an extra credit . It'll take you like five minutes
00:49 your life. Okay. And it's just a self assessment and ask
00:53 Are you ready for the exam? you studied this? Have you studied
00:57 ? How have you studied? How you think you're gonna do, Do
01:00 know it? I don't care what answers are, answer for yourself.
01:04 right. Because this is a self . This is something you need to
01:07 doing before every exam before you walk an exam, let's say. How
01:11 times have you ever got into an in your like I hope he didn't
01:14 ask this question. Right, so already know that's that's kind of a
01:19 self self assessment. Like I know haven't really studied this. Alright,
01:23 what this is trying to do is to give you a sense of what
01:26 know and what you don't know if know that going in an exam,
01:29 already know how well you're going to because an exam is not a device
01:34 determine what kind of person you It's a device to determine whether or
01:39 you learn the information you were All right. The stuff you should
01:43 studying is the stuff that we talked in class. That's where your focus
01:47 be. And so when you answer questions, like I said, we'll
01:50 you like five minutes you get 2.5 for your exam. Right Okay.
01:57 one it closes at nine a.m. On morning. So notice I want it
02:02 before you take your exam. So making you do it at the very
02:06 minute and it comes due before the . Now the second one opens up
02:10 a week later. Alright So once taking the exam you've had a chance
02:14 look at it. We'll have a one that says all right now tell
02:17 did you do the way you thought were gonna do? What did you
02:20 ? What would you change? but we're not gonna worry about that
02:24 because what's gonna happen if you don't that alarm on your phone, you're
02:29 forget until 9 30 on thursday morning you're gonna panic and then you're gonna
02:33 dr wayne. I forgot to do . I'm gonna say I'm sorry because
02:37 is for that small period of So that's part of the exercise is
02:41 able to remember that window. So put it in your phone and put
02:45 alarm, you know right before you to bed or something. So that's
02:50 the first announcement. If you didn't , just in case there's a test
02:54 thursday um third today, what we're do is we're going to finally leave
03:02 sort of, we're gonna get in tissue finally. Alright. Oh and
03:08 in case you didn't know were already quarter of the semester done.
03:15 Yeah. See there's the yay, what I was looking for the right
03:19 mean so to give you a sense how fast semesters go, we're already
03:23 quarter way done. And so what gonna do is we're going to walk
03:27 primarily epithelial tissue and connective tissue and once again we'll dip our toes and
03:34 say, oh yeah, remember there two other tissues here. But what
03:36 gonna do, we're gonna look at details of these two things and everything
03:40 today is going to be on the . All right. Um At right
03:47 class, what time does class in ? Yeah. I mean we get
03:52 earlier than that. But it's 10 , right? Is our window at
03:55 o'clock. That's when another document opens on blackboard and that's just a practice
04:01 , it is not a practice exam the sense that if you do well
04:05 this you're gonna do well, it's practice exam in the sense of these
04:08 questions that I've written. So you of get a sense of how I
04:10 questions, right? So don't use as a tool to say, oh
04:14 at how smart I am. And , let me see how dr wainwright's
04:18 . Alright, so, these are I no longer use on my
04:21 It gives you a sense of what's on. All right, so,
04:26 kind of dive into this. All . So, our starting point is
04:29 to be epithelial tissues. We've we've them briefly, right? We said
04:35 they're basically a sheet of cells. their job is to do is to
04:39 things. And if they don't cover . Typically we have another group that
04:43 refer to as glandular epithelium. Their is to make up the glands of
04:47 body and to secrete stuff. So typically when we think of
04:52 we think of the covering epithelium. , when you look at your
04:55 that's epithelium, if you open up mouth and look on the inside of
04:57 mouth, that's epithelium, basically any organ. The surface of that hollow
05:02 , both on the inside and on outside is epithelium all right. And
05:06 have these specialized contacts. We've already of seen these. Alright, So
05:10 connected by tight junction hemi does Mazzone's OEMs. And typically what they do
05:14 they form these sheets over and over . Just layers and layers of of
05:19 . Or it could be a single . Alright. Glandular epithelium is unique
05:23 that. It doesn't do that. when we get to glands, we'll
05:26 that. All right, of Alright. First characteristic of epic feeling
05:34 are a vascular. Alright. A means they do not have blood vessels
05:40 through them. Okay, So they typically served by blood by some sort
05:47 nearby tissue, but the blood vessels don't travel through the tissue.
05:53 so they're a vascular but they're meaning that nerve fibers can be found
05:59 them. Now, here's a little of, you know, factoid.
06:04 . You don't need to know this a test. But just in
06:06 there's no cell in your body. more than 10 microns away from a
06:10 vessel. Alright, If you don't what a micron is as a thousands
06:14 a millimeter. So, cells are really close to blood supplies. But
06:19 we talk about a tissue being a , that means there must be a
06:23 supply that comes very, very And then the materials from that blood
06:27 will actually penetrate between through the cells get to where it needs to
06:32 All right, So, this is picture we're gonna see when we talk
06:35 the integra mint. This is your . So up here this is
06:40 Up here, down here. This connective tissue and you can see we
06:43 blood vessels that travel right up next the epithelium. But don't actually penetrate
06:49 the epithelium. Have you ever skinned knee? Your elbow, Your arm
06:53 something like that? And it didn't . But you saw a lot of
06:56 come off. What you did is shaved off epithelium. You didn't get
07:00 to the connective tissue. All It's also a characteristic of epithelium that
07:07 regenerates itself. Alright, There are unique type of cell in that they
07:11 what we call contact responsive. So these cells are being lost or
07:18 what happens is they're no longer touching epithelial tissue. So like when you
07:23 a cut, you're basically you're separating epithelial cells. And these epithelial cells
07:29 to touch other epithelial epithelial cells. so what they do is they start
07:33 until they touch again. All And so that's what we say,
07:36 contact responsive. So they will continue divide and multiply until they come into
07:42 with each other at which point they , okay now I'm happy again.
07:46 , So this is a unique thing epithelium. This is why you're able
07:51 constantly replace your skin tissue. it's undergoing this constant regeneration as it
07:58 it um as it lives. And you damage it does it even
08:03 So, so we've talked about this little bit and epithelial tissue has polarity
08:11 it has a top and a bottom are unique and different or separate from
08:15 other. We refer to the exposed as the typical side. Alright.
08:21 if you look at your skin, is the typical surface, the part
08:25 not exposed. It's called the basil . And the ones on the side
08:28 called the lateral surfaces. And then just kind of combine basil and lateral
08:32 because they're very similar to one It's just direction, right? But
08:37 a pickle is very very different than lateral side. Typically. What you'll
08:41 in epithelium is that the typical side where you're going to be secreted materials
08:46 absorbing materials. And so they have unique surfaces. They're gonna have what
08:50 called micro villi. Or you might cilia on the surface of these
08:55 If you don't know what those we'll get to that in just a
08:57 on the basil side. What there instead is that the basil sites to
09:03 proteins to create this extra cellular matrix it can use to attach to the
09:09 tissue underlying it. Right. We to this as the basil lamb inna
09:14 it makes up half of what is the basement membrane. Alright. So
09:19 pickle side has unique features. That's we're going to secrete or absorb basil
09:25 secreting proteins so that it can attach the underlying connective tissue. So the
09:31 connective tissue is connected is the underlying is connective tissue. And it's a
09:37 proteins as well. It's a creating towards the epithelium and that's called the
09:43 lamb Inna. Alright, so we basil lamb inna and particular lamin
09:48 And they come together and they kind attached to each other like velcro.
09:51 so that's why these two tissues are to attach to each other very
09:55 And that's what forms what is called basement membrane. And this is what
09:59 your your epithelial or epithelium in And then you can go back to
10:05 example of the indian burn. And doesn't come flailing off hemi Desmond's OEMs
10:11 in there. You got the Desmond's attached to the cells. But it's
10:15 structures of that basement membrane. The Desmond is going into that particular laminar
10:21 attaching the proteins that prevents the skin being pulled off. Now I know
10:28 is texas. So I know there's couple of you in here are hunters
10:32 if you ever skinned an animal, you're doing is you're separating out the
10:37 from the underlying connective tissue. And of you who have not done that
10:41 you've ever bought chicken with skin on , you've taken the skin off you
10:46 leaving the underlying connective tissue. so if you don't know what microbial
10:53 this is the example here. There a cartoon. This is a I
10:58 know if that's electron micrografx. That's electron micrografx. Alright, so cells
11:06 jam packed close to each other. so what that means is they have
11:10 very very small exposed surface. so, if you can imagine me
11:14 a cell, this is kind of space right here. Right now,
11:18 I want to increase my surface I don't can't really increase myself size
11:23 I'm I'm jammed in there with other . So in order to increase my
11:28 area and I need to increase my area because it increases my ability to
11:32 materials or it increases my area to materials. Then what I'm gonna do
11:37 I'm gonna take my surface area instead it just going flat across the
11:40 I'm gonna extend it up and down up and down up and down.
11:42 of like Bart Simpson's hair. so, you can kind of see
11:49 , this is terrible for those of in the back. But if you
11:52 imagine if I have a cell that a distance like that. If I
11:57 up and down multiple times what I've as I've increased my surface area
12:06 right, I can be able to 100 times better than if I just
12:13 a smooth surface where we really see . And this is true in a
12:18 of different places, but where we see this is in the digestive
12:22 Your digestive track is about 33 ft . All right. And it has
12:27 these micro villi and all these other of modifications to it that allow your
12:34 ft long digestive tract to be about miles long. So that's why we're
12:41 to absorb food rather quickly because we this massive surface area that doesn't take
12:47 a lot of space. All right , if you're not aware of what
12:54 cilia is or psyllium psyllium is A cilia is basically going to be
13:01 with the musician secreting cells. So you see the word music, you
13:04 think of the word mucus. And correct mucus is a combination of water
13:08 a bunch of proteins. These proteins primarily members of the meuse in
13:13 There's a whole bunch of them, ? And so the purpose of the
13:19 is to take that musician and that and that mucus in general, which
13:25 binds up to stuff. It's very . Right? Everyone here is suffering
13:31 allergies right now. Right? This is sticky. It's grabbing all sorts
13:36 stuff in the air that you breathe its stuff in your throat, in
13:40 mouth. When you chew food it that that food and turns it into
13:45 bullet and kind of holds it It's sticky stuff. And the purpose
13:50 the cilia is to grab that stuff to move all the things that shouldn't
13:54 in your respiratory system for example. to pull it upward, it sits
13:59 and goes like this and constantly pushes moves the mucus and whatever it grabs
14:05 from the cells so it has this sort of movement. It moves material
14:10 its surface Now bacteria and I have right here um And and oh actually
14:15 gray this is not the bacterium but bacteria when you have a single cell
14:20 have cilia they kind of use it a way to move. And the
14:24 type of structure we have that allows to move in our bodies or the
14:27 ela it's only found on spermatozoa. this is not an epithelium and its
14:32 is to propel specifically sperm. Alright they're different in terms of how they
14:38 and structure which will see but and terms of functionality. But actually if
14:43 look on the inside structurally they're very similar. When we get to the
14:50 senses we're gonna see things called And they do stick up like cilia
14:55 but they're different and unique and their is to kind of help you with
15:00 to equilibrium and balance there. They're similar but they're uniquely arranged so that
15:08 body knows which way it's tilting. have you ever noticed that when you
15:13 dizzy? I mean I don't know can feel a car move or when
15:16 in an elevator going up and down stuff that's a different type of
15:20 it's what is referred to as the psyllium structurally very similar, but very
15:25 role. So when you look at silly and flagellum internally, they're made
15:30 of micro tubules. They have some proteins in there that helped them
15:35 And the really the key thing I you to understand is that their movement
15:38 different. So cilia move kind of an oar if you've ever seen an
15:43 in a car basically, or in car in a, you know in
15:46 boat or canoe, basically what you is you kind of do it like
15:49 ? Right? That kind of look , sort of? Right,
15:55 so that's, it beats like This is why it's able to push
15:58 . It's kind of like going, pushing it away, I'm pushing it
16:01 , pushing it away, so that's silly it work. All right angle
16:05 the other hand, there long and and so they have more of a
16:09 like movement, which creates the very kind of a propeller like movement,
16:13 is why why results in propulsion. why they're different because they create different
16:19 of movements back to the epithelium Alright, so what does epithelial do
16:28 epithelium do? Really? It's it's basic. Alright. First off
16:34 First thing it does is protection, protects the outside or the inside of
16:38 from the outside of something. It selectively permeable meaning it determines what's allowed
16:44 pass from that one environment into the environment. Third, it plays a
16:50 in secretion and conversely absorption. So able to, it's a cell that
16:56 takes and move stuff out into an or pulls things from that would be
17:02 of that selective permeability. And what we'll see is that some epithelium
17:07 a role in sensory reception. In words, they're there to help monitor
17:11 environment. Okay, so in this up here, remember the epithelium is
17:18 this pink part up here and then come down and look at it.
17:22 what we've seen before in this picture here where we can see secretion and
17:31 epithelium has depending on what you're looking . Two names. Alright. First
17:38 is always going to be based on number of layers right now, when
17:42 say that, that doesn't mean you to count layer, that's that's kind
17:45 the good news, it's either it's layer or it's two or more
17:50 So if you see more than two , you you know that you're dealing
17:54 multiple layers. Okay, If you see one layer then you're dealing with
17:59 single layer. If you're a single , we refer to it as a
18:03 epithelium. If you have more than or more, you are stratified.
18:10 simple epithelium is gonna be found where or filtration is taking place. That's
18:15 movement of materials across that single layer cells, when you're dealing with
18:21 Typically this is where protection is Alright, Now, whenever we see
18:28 the what I said is there's gonna two names. We're gonna see that
18:32 stratified cells, that there may be shapes of the cells as we're going
18:39 . And we're all be concerning ourselves the lowest layer when we deal with
18:44 shape, because that's the second Alright. Its shape. Now,
18:51 just gonna let you know now this not a panic movement. I
18:54 it's not we're not a histology Okay, So when I say we're
18:58 a histology class, that means I'm gonna give you some uh really,
19:03 difficult things to identify. But this an anatomy class and you will need
19:06 identify things. So, these are be pretty straightforward, right? I'm
19:11 trying to trick you when I show a picture, just kind of look
19:15 and go, okay, what is obvious answer here is what we're looking
19:19 ? All right. I'm gonna show how to do this when you get
19:22 histology. That's where it's like. not entirely certain what I'm looking at
19:26 . I've got to look for more than than the simple. Alright,
19:30 , with regard to epithelium, we're name it based on its shape.
19:35 so, you can see up here the cartoon, we have these three
19:37 . The most common shapes are listed . The first one is gonna be
19:41 flat shape. All right. This what it's called. Squamous squamous mean
19:46 like. All right. And so at it's at its best. It
19:50 kind of comes along and it looks , very flat, just like a
19:55 . And then the next side or shape upwards is gonna be kind of
20:00 shaped like a square. And this what we refer to as Q
20:05 All right. Now, they're not be ever be perfect. There's no
20:09 thing as a perfect looking cell. you got out measured the side of
20:13 top, you see that there's a . All right. But for the
20:16 part by naked eye, good you should be able to Okay,
20:20 , it's definitely about the same width it is tall. So, that
20:24 be considered cube oil. The third is that they're taller than they are
20:30 . And those are usually pretty obvious you look at them. It's
20:32 yep, that's tall and it's not wide. And this is Colombian are
20:39 the key thing when looking at an is finding where that basement membrane
20:45 Alright, You need to kind of and say can I see what this
20:49 is sitting on top of If I find that then that's going to help
20:53 make a couple of decisions about what this epithelium is All right.
20:59 you can kind of see in these , they're trying to give you a
21:01 base sewing look, you can see the bottom. So I'm sitting on
21:05 of that. And so my shape kind of defined relative to where that
21:11 . All right. That's that's Number one. Just look for what
21:15 attached to. Clue number two is you look at something and you're completely
21:19 totally lost, look at its the nucleus roughly mimics the shape of
21:25 cell. So, if you're looking a boil one, the nucleus is
21:29 be mostly round. If you look a columbus are one, you're gonna
21:32 something that's more like shaped like an . It's gonna be elongated. And
21:37 when you see uh squamous you're gonna kind of a flattened nucleus.
21:44 So those those characteristics are going to expressed not just in the shape of
21:47 cell, but in the structure inside the nucleus inside. So, when
21:52 look at it, we're gonna ask questions whether it's shaped, where's the
21:56 membrane? And then how many layers we see? Okay. And I
22:00 to start with the three easy The three simple epithelium. Alright,
22:07 , simple epithelium three types simple simple, simple Columbia. You can
22:12 see based on the name how many one and then the second name tells
22:19 shape. Alright now having said that your future, you're gonna come across
22:24 like helium and mesothelioma and you're gonna , wait a second. Doctor Wayne
22:29 show me those things. All They're just weird names for simple types
22:35 epithelium. Alright, so India thallium just a special name that they use
22:41 the epithelium that makes up the hollow , specifically in the lymphatic in the
22:46 system. So, when you look a capillary or if you're looking at
22:50 artery or any sort of the vascular of vein, you know, they're
22:54 to say the end epithelium of the is blah blah blah blah. And
22:58 they're really telling you is, it's the simple uh squamous epithelium.
23:05 you learn eventually when you when we through the uh the cardiovascular system,
23:11 that's the only thing you're gonna find it. It just has a special
23:15 . Okay, it's enough. Measles, thallium is just a special
23:20 for the type of epithelium that we in the serious membranes. You guys
23:25 talking about serious membranes a little bit ? Talk about the friction,
23:31 That that tissue there is just called . And we're just gonna leave it
23:36 that and you're not gonna have to them. It's just those awards.
23:39 see in the future. All So, what I wanna do is
23:41 want to look at those three that there first two, up at the
23:50 , simple squamous cartoon is obviously The real picture is a little bit
23:54 difficult to see. Can you even a basement membrane in there, Do
23:58 think? Now, first off, point out that these are really,
24:02 terrible pictures. The books gives you pictures because they have to buy a
24:06 to some of these pictures. And it's really hard for them to find
24:11 . So, they don't all So, usually when you get a
24:14 like this, it's like it's like a person 100m away. It's just
24:19 easy to do. But if you at this, can you find a
24:23 membrane and all of you guys kind did this kind of like, I
24:26 see any basement membrane. No. right. So, what we're looking
24:30 in this particular picture is the All right. And the basement membrane
24:35 not real obvious in this? And you're looking at here, the
24:39 Alright, so, there is basement . You just can't really see
24:42 If you kind of look around, can see say, like right
24:46 And these dark spots. Those are Now, you don't know that.
24:51 see I told you this is not course. Right. But what you
24:55 look at that and say, do cells look tall. Do the cells
24:59 tall to you know, do they square to you? No.
25:03 if they're not tall, they're not . What are they? They're
25:07 Do you see how easy that Okay, that's the type of identification
25:13 . Like I said, this is terrible picture. And I'm not gonna
25:16 to trick you on exam. I'm to try to make it easy.
25:19 long as you learn your definition, should be able to identify. So
25:23 should be pretty straightforward when you see flat thin simple epithelium. That's
25:29 squamous. Okay, again, this another one. I don't think it's
25:34 very good picture. It's from your . But what you wanna do is
25:37 want to kind of look in here say, okay, where are my
25:40 ? So you can see all those dots. Those are nuclei.
25:46 hard to see anything in here. see just layers upon layers upon layers
25:50 cells. But if you look what say is Alright, well, like
25:54 here, there's this kind of this stuff that sits in between and over
25:58 , there's an opening over there. that's the basement membrane that right there
26:03 a pickle surface. So these represent , you can do it at any
26:07 if you look at those cells are of roundish or at least those nuclear
26:10 of roundish. So those are a like cells. Now, when I
26:14 you a picture, it's gonna be that far away. It would be
26:20 , can you identify your friend a off Now? I'm gonna put your
26:24 right in front of you? But that's what you see here,
26:28 we're looking at around nucleus kind of box like shape. Yeah. To
26:35 you on this stuff is part of homework is gonna be pictures of these
26:40 of things to kind of go, , I see how this works.
26:44 , so it's not just one picture you're just trying to learn here,
26:47 you're not gonna see these pictures ever on an exam. These are just
26:50 example of one. Okay here, can see the optical surface, it
26:57 down, it comes up and goes , it comes up, it goes
26:59 . These are just other organizations. are actually this is uh you can
27:04 of see now that the inside of body is not perfect. And so
27:07 can actually see these are extensions of uh these types of crops that are
27:13 of moving off to the side like . So when they cut this
27:17 you're looking at a structure that kind went that way. So this is
27:21 a little further down. And you kind of see this would be the
27:25 membrane as it goes up, comes , goes up and we'll just see
27:29 one right there, that one right . And if you look at those
27:33 , you can see up here on top, that's the top of the
27:36 , that would be the basement Those are the nuclei. And if
27:39 look closely at those nuclei and I from here doesn't look so easy.
27:43 can see that those nuclei are nice elongate. They're taller than they are
27:50 . That simple columnar. Now, Columbia exists in kind of two
27:56 Sometimes they have cilia. Sometimes they . So you'd see if if they
28:01 cilia, they would call it silly Coloman are epithelium. If they
28:05 they'd be non silly ated. you can see it gets complex.
28:08 you need it to be you will need to identify this one on the
28:13 . But you should know its All right now, if you look
28:18 this, it's nice and simple. your basement membrane there, right?
28:25 is the top. You can actually see some silly up there.
28:29 And if you look at this, that look like more than one layer
28:32 you? Yeah, you can see dots. The dots represent nuclear
28:36 There's a dot on top of another on top of another dot.
28:38 there's one up there. All But if you went in there and
28:42 those cells apart, you'd find out are all one layer of cells,
28:48 is why this is not a histology . Right. This is called pseudo
28:55 . Alright, pseudo stratified is a epithelium but it looks like a stratified
29:05 . Alright, we find these in whole bunch of different ducks, different
29:09 of glands. But when you look it you'll see that some cells make
29:13 all the way to the optical Some cells don't. And so it
29:17 an appearance as if it has all different layers to it. All
29:22 But it is a simple epithelium. right, pause there for a
29:29 So far. Are we okay with simple feelings? I mean layers and
29:33 how do we identify them? Shape nucleus? Right. Find the basement
29:41 . Find the optical surface and then of look between them, stratified epithelium
29:48 multiple layers of cells. All And so what we're gonna do is
29:54 living layer, it's I mean all could be living not all of them
29:59 like in this particular case they're not gonna be what we do to go
30:02 the basil layer. And we oh so this is the layer that's
30:06 dividing. And what they're doing is as they divide they get pushed up
30:10 from the basal layer and they go the april a pickle layer and these
30:14 a major role in protection and this of makes sense that it does the
30:18 layers I have, the harder it to get through that. Right?
30:23 you can have like on your skin it's very difficult to have like 40-50
30:28 of cells. And the closer you to the surface, the smaller and
30:33 the cells get. Now. Remember said in terms of nomenclature, we're
30:38 to name them based on the basal , not on the optical layer.
30:44 , if you can see up we have squamous looking cell down
30:48 Right? I say that right? , no, I'm I'm sorry,
30:54 that, scratch that out. We're be based on a pickle service.
30:56 the surface that we can see. don't name it on the basil
30:59 Right? So, what we do we say this is a squamous
31:04 Doesn't matter what's down here. It what we can see up there.
31:12 , here's the first one stratified This is the only squamous layer.
31:17 think you're gonna need to know on exam. I'm gonna show you why
31:20 just a second. I'll show you . Okay, so the primary reason
31:26 that this stuff is everywhere. All , This is your skin and this
31:29 the stuff that you find in those zone as you move from your skin
31:34 the oral cavity, the nasal the anal cavity, vaginal cavity.
31:39 there's a cavity urethral cavity as you moving into them, you have these
31:44 of layers out here on the We have a tough protein that's involved
31:51 giving it more strength. It's what refer to as carotene. Ized,
31:55 not gonna have to distinguish between criticizing criticizes just knowing what it is.
31:59 , if you took your fingernail and it across your arm, are you
32:02 cause it to bleed? No, your fingernail and put it on the
32:06 of your mouth and scratch it across inside of your mouth. I think
32:09 gonna get it to bleed. probably. All right. So what
32:13 you say is your skin tougher than inside of your mouth? Yeah.
32:16 . And it's because of these So carotene eyes has these keratin proteins
32:22 give strength to those structures. All . Non criticized on the other
32:29 are found deeper in those internal They don't have that same keratin.
32:33 they're a little bit softer. All . But you can see regardless that
32:39 layer, you can see up there upper layer. It's a squamous structure
32:45 low. I don't know what it . It could be Columbia, it
32:48 be cube oil sometimes it's a mixture both. All right, so we
32:52 care about that later. But you see there's multiple multiple layers.
32:57 so the skin is a really, good example of seeing that and everything
33:02 falls into this other stratified. these structures are a little bit
33:07 a little bit more rare in the . Alright, so stratified cube
33:11 Again, you're looking at that a layer and you'd be oh look at
33:14 outer layer is kind of cube boil shape. Here's an example you can
33:19 here is the outline of this There's layer, number one there's layer
33:24 two, you can just kind of around. And so that that layer
33:28 that is facing the a pickle surface that tube is cute, boy.
33:33 at the nuclei. They're mostly So that outer layer is mostly
33:39 We don't care really what it It's just that inner layer. So
33:43 is typically what we see in glandular . Alright? And then we have
33:48 columnar and you can see male urethral gland. So instead of being
33:53 it would be elongate in that our layer. All right. But I'm
33:59 gonna make you try to identify those on the exam. Alright. It's
34:05 three symbols. And the one stratified . You have to identify pseudo.
34:14 , but you should know what it . Here's another one. You should
34:18 what it is, but you don't to identify it because this is the
34:21 tissue. Look at its name, . Right? Great. When you
34:27 the word, transitional, what does , what does it sound like to
34:30 , changes? Yeah, great. . All right. Think about your
34:37 . Your bladder is actually like a . It actually folds on itself.
34:42 . And then, over the course the day, about every minute you
34:45 about a millimeter to two ml of to your bladder and it slowly expands
34:53 then it stretches. Right? And when you're like, I've got to
34:57 up and go and then you evacuate bladder and it shrinks back down again
35:01 its original deflate itself. All Those cells when they get stretched change
35:10 . So they start off kind of oil in shape. But then when
35:14 fill up that bladder they stretch out they look like squamous. So what
35:21 they? Yeah, they're kind of . So that's what we call
35:25 transitional. Alright. The a pickle varies in appearance depending upon the degree
35:31 absorption or disagree of this degree of is what I was trying to go
35:38 . Alright, so I know what is but you're not gonna see a
35:44 like this because we leave those for and when you go to nursing school
35:52 get a whole class on being able identify those tissues. Yes.
35:59 Questions about how we name epithelium. . Yeah like they're not right.
36:14 . So so again, so the is with stratified squamous. So whenever
36:18 dealing with stratified tissue you're always looking the local surface, not the basil
36:24 for its nomenclature. I was I a brain fart when I was saying
36:27 earlier. Alright, so you look that outer layer and say what does
36:31 outer layer look like to me. , so again it's the squamous you
36:38 it's scale like up here. So a squamous tissue. If it's cube
36:43 right? That outer layer that we to as Q. Boil. If
36:46 tall then it would be you stratified . We don't care what the bottom
36:51 looks like. In fact, when look at uh the stratified columnar,
36:55 bottom layer is usually two layers, layers, cube oil looking. And
37:00 you have the tall ones on So again, bottom one doesn't
37:03 It's only the top one. That . Only the top one matters.
37:09 right, glands. Alright. Remember still in epithelium here. So we
37:17 tissue that's protective that can absorb or . And now with glands were now
37:23 longer protected. We're now primarily secretion . All right. So a gland
37:29 is one or more cells. That's because we have uni cellular glands in
37:35 bodies. One or more cells, secrete some sort of product.
37:42 so secretion is to release or to to the surface. Um And the
37:47 is the stuff that you're actually So typically what we're looking at is
37:51 sort of acquis fluid. So it's plus stuff. Typically that stuff is
37:56 but depending on what you're looking there may also be other things in
38:00 , like lipids or even steroids. way we classify glands is we ask
38:05 question of which direction are used to materials. If your psa creating things
38:10 the surface of the skin, then we refer to. That is
38:16 If I'm secreting into a hollow that's excellent. With the exception of
38:21 type of of hollow organ that we're to is um let me back
38:27 I'm gonna make this easier for Alright if that hollow organ is open
38:33 the surface. Alright, so think your digestive track is your digestive track
38:37 to the surface of your body. I went like this, I'd have
38:42 tube through my entire body like a . Right? You are donuts,
38:48 ? Your digestive track is external to body. Okay? I know that
38:54 weird but you couldn't put a hamburger your mouth if it was inside your
39:01 , it has to be outside. . If I want to get a
39:04 into your body, have to cut up and jam it in there and
39:06 it back up. Kind of weird system. Is it open to the
39:12 or open to or is it Open? I can breathe air into
39:17 . It's basically a big old Okay, urinary system open to the
39:23 . Yes. Right. Well, mean you're not peeing into your
39:27 You're peeing out of your body, ? So these are structures that are
39:31 to the external environment. Alright. that are inside your body do not
39:37 contact with the outside environment. So example, your blood vessels are closed
39:43 there, part of your body. internal to you. They never come
39:47 to the surface unless you cut a . Right? So X. Akan
39:55 secrete externally. That means I can into the digestive track. I can
40:00 into the respiratory tract. I can into the renal tract. The urinary
40:06 . I can secrete onto the surface my skin. That's all external.
40:12 I'm internally secreting. Alright. That be endocrine. Alright. So,
40:18 what we're doing is we're secreted into fluid of our bodies. So into
40:22 bloodstream, into the interstitial fluid. right. When we talk about endocrine
40:28 , typically what we're talking about our producing glands, they're typically ducklings and
40:33 typically not made from epithelium, but call them glands because they're producing a
40:39 that gets put some place. It's secreted outward away from the gland.
40:45 , what we're primarily focusing on here we talk about glands are the extra
40:48 glands. Alright. And what we is we basically name them based on
40:54 their structure is. Alright. this is structure. We have uni
41:01 . How many how many cells in uni cellular one. See how are
41:05 is? Or we call the which is more than one. All
41:11 . So, this right here is example of a uni cellular gland.
41:15 right here, if you look at , what do we have? There's
41:19 basement membrane. So, you have simple Colombian are epithelium and jammed in
41:29 . You have these types of They're called goblet cells. They're called
41:34 cells. Because they look like a . You know, the goblet is
41:41 it's basically like a chalice. It's a stemmed uh cup that cup holds
41:47 the liquid is. Right? And the goblet contains within it, the
41:54 that they're gonna be secreted, primarily . And you can see in our
41:58 epithelium up here there is your And if you look really closely you
42:02 see a layer of mucus and you imagine what's making the mucus, the
42:08 cells and it gets up there and the epithelial cells are sitting there going
42:12 go that way. Alright, pushing around. All right. So again
42:17 is the process of X. Acidosis and whatever the product happened to
42:22 in this case it's mucus. Most glands are what we call multicellular
42:30 They're rather complex but in a very sense they have two parts to
42:35 They have a duct and they have region that's responsible for producing this product
42:41 they're making. And that region is the escena. All right, well
42:46 plural escena hasina's is singular. So like this you can see here's a
42:52 and in this particular case the duck multiple times. You get down to
42:56 little ins and you can see a orange dots those are the escena.
43:00 that's the complex nature of a Alright. So typically these are formed
43:07 development when you're talking about some sort epithelium. And what it does is
43:11 bends downward. That's called inv Sometimes you may see ev agitation which
43:17 the other direction kind of bulges And then the ducks and the areas
43:23 the casinos are gonna be. Those going to form what are called
43:27 And those lobes are separated from other . Because there's connective tissue that has
43:30 of penetrated in. Or you can of it the other way is that
43:34 the imagination has penetrated into connective And so you have these things that
43:39 of create the unique structures, the lobes where the materials being secreted.
43:46 . Typically you're gonna see blood vessels nerve fibers surrounding them. Why?
43:51 , I need to deliver materials so can secrete it. I need to
43:55 it when to actually do this All right. So, we can
43:59 multicellular basically based on their anatomy. other words, what is their shape
44:05 structure? Or we can look at and ask the question, What are
44:09 secreted? And so structure is the part, even though these pictures are
44:14 , This artist really screwed this So, I'm gonna walk through.
44:18 right. So, what we're looking here, we're looking at ducks and
44:21 looking at a scene i or a . Alright. So, when the
44:27 is simple. So, this should be going down. So, in
44:31 pictures, the light purple color. that lavender? Okay, I'm just
44:38 know eight colors. Yeah, lavender works. Alright, so the lavender
44:44 ducks. Okay, So what this do, that should come down a
44:48 ways. The artist didn't do So that would be the duct If
44:52 doesn't branch. If the duck doesn't , it's called a simple gland.
44:58 , so over here, if you at this, you're like,
45:00 wait a second. I see but it's not the duck that's
45:05 It's the structure's branching from the Okay, So this is why that
45:12 right? There is simple. All . If the duct branches and what
45:18 should have shown here, is this off that way as well? Going
45:22 that way. Kind of like you in these in this picture right
45:25 Same thing there when the duck has branches to it, then we call
45:30 compound. Alright. Now again, have to probably identify one of
45:37 But the pictures I have on the should be easy. Alright. I'm
45:44 trying to trick you. I know sitting there thinking he's trying to trick
45:48 . No, that's not what I stuff is hard enough without having to
45:53 you. Okay. All right. , first we looked at the
45:57 Is it as simple as that branch and un branched its branches compound.
46:01 it's un branches simple. All In terms of the casinos, you
46:05 at the shape of the casinos This artist really didn't do us any
46:09 . All right. So if you at this, the shape of the
46:14 is the same shape as the In other words, it doesn't bulge
46:19 like a grape. It's kind of same shape as a tube.
46:22 If it's the same shape as a , we refer to it as
46:26 Alright. So if the duct in tube at the introduction the same at
46:31 end, look the same. It's . If it's Al Viola, that
46:36 that you bulged out. Kind of a grape. All right. And
46:40 you can see this kind of bulges like a grape. Right? So
46:46 would be Al Viola over here. Viola kind of looks like a tube
46:55 and then some ducks just want to with you. And so you'll have
47:00 that are Al Viola or some that tubular mess we refer to as
47:03 Al Viola. Alright. But you see the same structure. We have
47:08 mixture of both types of casinos. right. So that's how we classify
47:15 anatomically? Look at the ducks. they branch or no? Look at
47:19 shape of the casinos or the Are they roundish or are they tubular
47:25 nature? Secretion? Is the other ? All right. So there's three
47:34 types of ways of secreted if your . So if you secrete one way
47:40 this type. If you create another or the other way. The first
47:43 is gonna be american american is what probably think about when you think about
47:47 grand gland. All right. I've to sell its making product. It
47:50 that product that puts it in a , vesicles floats to the surface when
47:53 told to, it releases the product into the environment. So that's the
47:58 of secretion via X acidosis. That be american. Alright. The product
48:04 is not altered in any way whatever have inside the vehicle when it
48:08 that's what you're getting. So the this would be lachrymose glands. What's
48:11 lachrymose glands, Your tears good. . Soft one person. It's your
48:16 ducts. So kind of think about tears kind of watery kind of stuff
48:21 them. You ever notice like when taste your tears tasted tears of your
48:27 . Alright, salty, bitter. , so there's stuff in there.
48:31 right. Think about your salivary glands ? Mostly watery. I'm not talking
48:36 the you know, that's that's mucus your throat. But basically, you
48:40 , that's that I think about when walking around outside, you can get
48:44 slimy, sweaty feeling, right? primarily watery. So notice what mary
48:49 glands are. Its water plus Alright, african grinds a pack,
48:56 glands are a little bit different. they package their materials in the
49:01 But what happens is instead of having vesicles merge with the surface and release
49:05 material, the vesicles is actually pinched with a portion of the cell.
49:10 so now you have a vessel inside membrane bound structure. Okay, and
49:18 it creates this, you're losing portions the cell as you go along.
49:23 . The example of this is a gland and the cell that got pinched
49:27 , it's gonna repair itself as back membrane and stuff. So, what
49:32 doing here now is is it's a bit different. So, think about
49:36 . Think about cream. Cream would an easier one because I'm sure not
49:39 of you are familiar with mother's Right, So, cream is probably
49:43 better way to think about think about thick it is, kind of fatty
49:47 nature, right? Milk is very than cream is. But those,
49:52 things are basically those materials separating from other. So, the idea here
49:57 you're adding in materials on top of stuff that you're actually making and that
50:02 you're adding on top of it is of the cell itself is getting pinched
50:07 . 3rd type is the Holocron. right here, I want you to
50:12 about sebaceous glands. All right. about those horrible nasty blackheads and
50:21 And you wake up in the morning you've got that volcano sitting in the
50:25 of your forehead. Big old white head. Right? What's happened here
50:30 the cells that make up that gland actually they build up their product and
50:36 that cell ruptures and releases its product into the duct of the gland.
50:43 , that ceb um which is the that they've made is now in that
50:49 and it slowly moves to the surface creates the oil that protects you from
50:53 sorts of horrible organisms that are living on the surface of your skin.
50:58 , now, why do I point blackheads and and zits and stuff like
51:02 ? Because that's when that's even gets because of dirt or other things get
51:07 in that in that duct. And it sits in there and then your
51:11 responds by saying, oh, infection then you get swelling up and
51:17 All sorts of horrible things. All , But notice what the cell did
51:22 . The cell didn't secrete material it at first and then the cell
51:28 It released its material and it got by another cell. And that's what
51:33 is. Trying to show you. cell itself ruptures and gets replaced by
51:37 cell. So, that's going on the escena of these sebaceous glands on
51:44 skin and also wherever you have Okay, so easiest one, american
51:55 pack Quran, the weird one because cell sticks around in the last
51:58 Cell suicide and release my my Okay, that's hollow. Okay,
52:08 here. Questions about epithelium. just get me out of here,
52:17 ? Yeah. The examples I think the best way to help. As
52:22 saw that look that look on her . She looked up here and she's
52:24 kind of just shook her head. like, I don't know. And
52:27 really what it is the easy way do this is think about what I
52:30 and then think of the example. example I think helps you best understand
52:36 . Right? So use the example help you remember what it is.
52:44 , connective tissues. What do you connective tissues do connect seeing that
52:51 Yeah, it's I wish it was that easy. But for the most
52:55 their job is to help bind things . See I have it right there
53:00 support. Play a role in insulation. That includes physical as well
53:04 immune protection. Um They play a in storage as well as a role
53:09 transportation. So when we think of tissue, it is the most abundant
53:15 in the body. It's everywhere. . And depending on where you're looking
53:19 and what type of tissue you're looking . You're gonna see it arranged in
53:23 unique and varying ways. All So it's not as simple as that
53:28 , where you're like, oh look just layers of cells. There's different
53:31 of connective tissue because they play so different roles. And that's why I
53:36 of show you that picture here is are just examples of connective tissue can
53:41 here. Bone cartilage, there's connective , proper blood. These all fall
53:45 the category of connective tissue. We're go over these in terms of their
53:49 categories Now, characteristics of connective all connective tissues have what is called
53:55 ground substance. Ground substance is a word for saying the environment that makes
54:01 the connective tissue. Alright, it is non living material, meaning
54:05 not cells. All right. It's environment where those cells and the proteins
54:10 those cells make reside. So, water plus stuff is the way you
54:15 think about it. All right. , typically, it's a bunch of
54:19 fibers. They make up the extra matrix. This cartoon is trying to
54:23 you you can see all the fibers of going everywhere. Right? But
54:27 the water and the other stuff that can't see. It's really this
54:32 This pinkish space in between all the that you see here, all the
54:36 that you see here. It's that that you're looking at. And if
54:41 went down to the microscopic level, is really what you would see.
54:46 , So large molecules that are attractive water that hold the water in
54:53 So, these molecules include things called Bly cans. All right.
54:58 when you see a word like you have to kind of break it
55:00 and say what is So propio from glide is usually referring to sugar.
55:07 ? So, it's a protein not a sugar. Protein which is
55:10 confusing because those two things are different like the gasoline, your car is
55:14 different from the sugars that you One is a carbohydrate, one's a
55:19 . Alright, so proto black hands basically these proteins and sugars that are
55:25 that have charges to them that attract and create this environment that holds the
55:31 altogether. And within them they have bunch of cell adhesion molecules and that's
55:36 everything is attached. So you can there's uh asian molecules right there and
55:40 kind of holds everything together and it this network that is kind of invisible
55:45 everything is kind of sitting in. is what the ground substances. Now
55:54 connective tissues have cells within them. , So there they are living
56:00 So depending on which is the primary type is going to tell you which
56:05 of connective tissue you're looking at. there's a nomenclature that we use when
56:12 look at a cell, it's gonna a prefix and it's gonna have a
56:15 . The suffix can be blast or . Alright, blast like explosion or
56:24 . When you see blast at the of a word that is referring to
56:28 immature cell when you see site that's to a mature cell. All
56:34 And so then what we do to at the prefix and ask the prefix
56:37 us then what connective tissue we And whether we're looking at that immature
56:41 cell. So, for example, connective tissue proper. The primary cell
56:47 you'll see there is called a fibroblast a fiber. Oh site. If
56:52 in cartilage, it's called a Kandra or a condo site. And
56:59 if you're in bone osteoblasts and osteo . All right. So, you
57:05 of just look at themselves. if I see this name, what
57:08 am I looking at? It's either tissue proper or maybe it's cartilage or
57:13 here. Maybe it's a bone. if you're looking for example, in
57:18 tissue proper less. So in the two, you're gonna see other
57:24 All right. So, for you might see at ePA sites at
57:28 site, basically the fancy word for cell. And so you'll see things
57:33 kind of hanging out now if you there and you see nothing but fat
57:39 . And you're probably looking at a tissue called adipose tissue. Okay,
57:44 just call fat tissue adipose tissue. a type of connective tissue. All
57:50 . But you might see mesenchymal Mesenchymal cells are the stem cells to
57:55 the other cells that we've just been about. So, when you first
57:59 creating that tissue, when you're in , you had mesenchymal cells. And
58:04 they differentiate, divide and they're still so that you can give rise to
58:08 cells again. All right. And you'll have things like immune insights.
58:13 kind of cruising through some that are around because this is like where they're
58:18 to be watching for damaged tissue are for infection pathogens. But you might
58:23 immune insights actually just kind of strolling the neighborhood, just checking things
58:28 making sure everything's okay. All The other thing I'd point out when
58:34 looking at connective tissue, When we about epithelium, everything all the cells
58:38 all touching each other all close together tissue. The cells are distance from
58:45 other. They're not all bunched up . Now. That's not always gonna
58:50 true. Out of sight. You see that We'll show you some examples
58:53 like wait a second. Aren't those together? Yes. But generally speaking
58:58 cells or not. It's the fibers make up the majority and the ground
59:05 makes up the majority of the The cells are typically separated from each
59:09 . So this is kind of a example of this um of of looking
59:14 how the arrangement of connective tissue kind looks. Even though I'm gonna be
59:19 about fibers here. So you can their cells there here there and
59:23 But they're not necessarily touching each right? You can see ground substance
59:29 there and you can see we have types of cells. So here's an
59:32 that would be um I think what doing there. Let's see. You
59:35 those are mesenchymal cells. The purple are the fiberglass. Here's an immune
59:39 site, there's fat cells at sites in this particular thing. And what
59:45 can see here in this particular cartoon they're just trying to show you there
59:49 three primary types of fibers. These the only fibers but they're the ones
59:55 you primarily see everywhere. So we collagen fibers, they're very long.
59:59 very flexible. Alright. I mean all young and tight still. You're
60:04 old and floppy yet. But I think about grandma once you put your
60:09 out and the bottom of her arm of does that you know that
60:14 Right. I mean look at I used to be tight. I'm
60:17 tight anymore. I got this going . I'm not happy about it
60:21 Right? Collagen in your face begins sag. Right. But it's
60:29 What is one of the things that do to tighten up our collagen
60:34 Yes, Don't do that. Alright. Anyway, there's about 25%
60:40 your body's protein is college. There's lot of it everywhere. Alright.
60:44 what collagen fibers are. Then we little ones that kind of go all
60:48 of different ways. A branch They're very tough, tough. But
60:51 also flexible. We typically see these of fibers called particular fibers within
60:57 And they serve as the strom a the network on which other cells kind
61:02 hang out. Alright. So particular is another type of fiber that you'll
61:07 short and tough. Uh Typically have glycoprotein attached to them. And then
61:13 elastic fibers, they contain a protein elastin. They branch a lot.
61:18 what they do is they have this to spring back into shape. And
61:21 you can play with your ear if want to you can pull your ear
61:24 like this right? And it just right back up. Okay? You
61:28 go to sleep and it falls like ? No, you've never done
61:32 It's terrible. Yeah. Don't do . All right. So that's
61:38 Alright, so elastic fibers. So can see for example in my ear
61:42 have elastic fibers, right? And cartilage in my ear. Um That
61:48 it to to bend and stuff like same thing in my nose,
61:52 My nose shifts back and forth because have elastic fibers and elastic cartilage the
61:59 tissue there. You will be affected a person. Yeah. You pierce
62:03 the cartilage itself. Yeah. So you're you're basically just putting a hole
62:09 it's a hole punch. Mm. , no it's it's not gonna loosen
62:16 . I mean over time it's going start but not as badly as
62:23 Again look at look at look at people. Alright. Don't judge
62:28 Just look at them be observed That's a better word, observe old
62:33 and look at the different parts of bodies that are sagging, right?
62:37 know, you'll see things like your sag. It's It's sad. We
62:43 get old. All right, good about connective tissue. It's pretty straightforward
62:49 . Alright, So, we have that's called connective tissue proper.
62:53 when you see the word like connective proper, what is that kind of
62:56 about this type of connective tissue? is what I think about when I
63:00 of connective tissue. All right. called connective tissue proper. Because generally
63:06 , when we look at a connective , this is kind of what we're
63:09 at. There are different types of tissue proper. Alright. All of
63:15 , all of them feature this relatively cells and And protein fibers.
63:22 The fibers are irregularly arranged. So can kind of look up there and
63:26 of see that lots and lots of substance and their job is primarily support
63:32 surround other organs or structures. three basic types are aerial or at
63:39 post in particular. Now, notice the terms connective tissue proper. What
63:44 looking at here is a subclass of called loose connective tissue with a name
63:49 loose connective tissue. What do you ? It looks like? It looks
63:54 like there's space in it. look at this. Does it look
63:58 there's space in between the stuff. . Does it look like there's space
64:02 between the stuff. Some of you gonna sit there? No. And
64:06 right. There is no space in . But you can imagine the first
64:09 they cut through fat tissue and slice it, you can't see the
64:15 Right. It's basically comes up as the outlines of the cells. So
64:19 looks like there's nothing there. But truth is actually the cells are really
64:23 together. And you can see here the outline of the cell. It's
64:26 filled with fat. But it gives the appearance of loose. That's why
64:29 falls in that category. What about here to the cells and the fibers
64:34 like they're jammed in or they look there's space in between it. Space
64:37 between. All right, so, is called areola at a post.
64:42 the primary feature of adipose? It's fat cells. Adipose, adipose
64:47 And then right here in particular, do you think? The main feature
64:50 particular is reticulated fibers? Okay, that's kind of its feature.
65:02 if loose connective tissue has an appearance loose associations. Not a lot of
65:08 . Everything. There's space in What do you think dense connective tissue
65:12 tight. Oh my goodness. Now, again, same, same
65:16 of rules. There's not a lot approach. I mean, there's not
65:18 lot of cells close together instead. we have now are a bunch of
65:23 proteins and those proteins are filling up creating those fibers so that the space
65:29 filled up so the ground substance is . The number of fibers is
65:35 The number of cells taste more or the same. Alright here, the
65:39 is the dominant fiber. And there three basic types dense, regular,
65:43 , irregular, in elastic. And you can look at the names when
65:45 see dense regular. What do you that means versus irregular structure. So
65:53 have regular organization. So again, a great picture, but you can
65:58 up here the little purple dots or pink dots represent where the cells
66:02 That's really the nuclei. So that's the cells are located. So everything
66:07 up there that's pink. Our fibers look at the fibers, they're all
66:12 in the same direction. Do you space for the ground substance in that
66:18 ? A little bit right there, little bit right there some over
66:21 you can see that and those might artifacts of of just the the slide
66:26 made so there's not a lot of substance, but you can see the
66:31 are all moving in the same They're densely packed moving in that
66:36 So dense regular. Next one down dense irregular. Look at the
66:43 they look organized to you. They're in all sorts of different directions.
66:49 quite as tight. And that means there's space. But what we have
66:53 is we have fibers kind of going way kind of going that way there
66:57 arranged. Hence the name dense And the last one here, this
67:03 elastic. I've been trying to figure why they call elastic for years.
67:08 do you think? Elastic? they're elastic. Okay, fine.
67:13 trying to show you this didn't rocket . You don't have to go get
67:17 engineering degree to figure this stuff Alright, elastic tissue has elastin in
67:23 , That means it's stretchy. so elastic fibers, so it's falls
67:28 the category of dense connective. And you can see the fibers themselves are
67:32 dense but you are made up primarily the elastin as opposed to the collagen
67:40 group. So that was connective tissue . We had dense connective. We
67:45 uh we have loose connective, we three types of loose, we have
67:49 types of dense on the cartilage. have three types of cartilage, cartilage
67:56 . What? We have our right? These Kander blasts and condo
68:01 blasts are responsible for creating the They release the proteins that make up
68:05 surrounding environment. And this is a solid. So the fibers are are
68:10 are close knit. And so what end up happening is is you kind
68:13 create this gel like substance that it the cells in them. And then
68:18 the cells get trapped and they can't , you know from each other.
68:22 can't make any more than they mature become the compromise. And then their
68:27 is to maintain the matrix that they've . Alright, so Kander sites are
68:32 mature forms. So this would be the countryside. These two right here
68:35 be Condra blasted kind of close So what you see here is now
68:39 pushing themselves apart and they're making matrix between them. Now here we don't
68:45 any blood vessels. So materials that cells need to live have to travel
68:49 the matrix in which they're found very strong, very resilient and
68:58 very similar to bone, but more than bone. And again, you
69:00 play with your nose, right? primarily cartilage up here. That's bone
69:07 move. All right, so three . All right. They have different
69:11 , different distribution of cells and so kind of behaviors. Alright, so
69:17 cartilage when we think of cartilage is typically what we think of.
69:20 they're trying to show you here are ribs, right? So that would
69:23 cartilage right there. Highland cartilage, cartilage already showed you to my
69:28 It's really bendy um cells, you , the structure moves fairly well.
69:33 then we have fiber cartilage and here can see kind of this regular,
69:37 can see little tiny cells in But what we have are these uh
69:41 and lots of collagen that's ordered in of a fixed way when it does
69:45 creates kind of a fiber structure. this is more stiff in terms of
69:51 structure, it helps to resist So we see these in the disks
69:57 are found in the there the inter disc of the of the spinal
70:03 Alright, so that's cartilage. Living makes their own matrix. It's a
70:07 like matrix. Semi solid fibers are there So far. So good.
70:13 . Next one's bone. Oh no not blood length. Thank you.
70:17 so this is the weird one. . And the reason blood and lymph
70:22 connective tissues is or uh developmentally they from the mezzanine kind. All
70:29 But it's weird in that this is connective tissue that the cells that are
70:35 within the fluid. So that would the matrix. Those cells don't actually
70:40 their matrix, right? These cells exist within them. Alright. So
70:45 blood itself consists of two parts. have the formed elements. So what
70:50 what we call the cells. And reason they use the word formed elements
70:54 that some of these structures like accurate throw sites have been modified beyond
70:58 cell stage. They're no longer living . They're more structural than sell like
71:05 have cell like features but they're not living cells any longer when we get
71:11 blood and A and P. You'll understand why. Um Then we
71:15 like Lucas sites, these are the insights um that are in circulation.
71:19 are blood cells. So the ground called plasma plasma is made um by
71:28 structures. And so it's not made the actual cells, lymph is the
71:36 that has leaked through the capillaries and picked up into the lymphatic system.
71:41 it's basically the same fluid. It's now in a different place. And
71:45 difference is is that because the fluid move but the proteins in the plasma
71:50 . It's it's basically plasma minus its proteins. Alright. And what we're
71:55 is we're just taking this and we're it back into the body and this
72:00 a function of how our capillary system . Which we don't need to understand
72:04 that lymph and blood are more or the same thing. They just limped
72:09 missing plasma proteins that the plasma actually . Alright, this is what we
72:15 the fluid connective tissues. Last one , just make sure I'm getting this
72:22 . Yeah. Last connective tissue is tissue, what we call bone.
72:27 . So it's very very similar to . The difference is very very hard
72:32 much more rigid and the reason for is that when it's being made it
72:38 into that matrix, what are called salt? It's calcium carbonate.
72:43 And so we get this really, strong stiff structure. Now we're gonna
72:49 this in more detail after the test we talk about bone. But these
72:54 black dots right here represent where living are actually located. Your bone tissue
73:00 a living tissue. It has living in it. And those living cells
73:05 nutrients and they do stuff to the bone. Alright, So it's not
73:10 hard stiff tissue, it's very much . So we have osteoblasts that make
73:18 ground substance and build the structure of . And then once they become
73:23 those cells mature become osteo sites and job is to maintain that structure to
73:30 that the the structure is able to what it's designed to do which is
73:34 support your body and provide for Now here we're gonna see like in
73:41 particular locations that there are blood vessels are traveling through it to bring nutrients
73:46 by. All right. So we that bone is both vascular arised and
73:52 . Alright. Has nerves help you that? It has nerves. Have
73:56 ever been kicked in the shin? you felt it? You felt
74:00 Because there are nerves there. Alright. We're getting down towards landing
74:09 plane. I looks like I talked , really slowly there. Um So
74:15 regard to muscle and muscle, there's much to say here just plays a
74:19 in movement. There are three different . They have unique features. We're
74:24 talk about all the different types of . Later with regard to the nervous
74:28 , there are two major types. already mentioned these before. We have
74:32 . They play a role in transmitting . Glial cells basically support nerves.
74:38 neurons that play a role in Alright. But there's a couple of
74:44 here at the end that become Alright. I think I can get
74:47 them in the last five minutes First thing is tissue repairs alright,
74:54 repairs itself. Almost all tissue in body repairs itself. Um Some does
74:58 very, very slowly to the point that slowness actually looks like it's not
75:02 repairing itself and some does it fairly . But the two major types are
75:06 be what is called regeneration and When you're dealing with regeneration, what
75:11 doing is you're replacing the destroyed tissue the same type of tissue. So
75:14 restore functionality. Fibrosis is when the is so severe that the underlying connective
75:20 actually fills in for the damaged And so what you end up with
75:24 fiber in those particular locations. for example, um if you cut
75:30 right, and it's not a deep , what you'll see is that the
75:33 kind of forms and goes back and doesn't look like you've ever been
75:38 That would be an example of But if you end up with a
75:41 cut that ends up with this large that sticks with you for the rest
75:44 your life, you know, one down here and it's right there actually
75:48 That's just one of several of stupid that I did in my life.
75:52 what you end up with is that end up with this structure that doesn't
75:57 the same functionality as when it Now when you're dealing with the
76:01 that's not gonna be the same But I'll give you an example of
76:03 student in class a couple years He said, well doctor in a
76:06 of years ago, I got hit the head with an ax.
76:10 And I said what happened there? it's like nervous tissues, one of
76:13 that goes through fibrosis rather than the . So the neurons that were destroyed
76:18 replaced by the glial cells and they up that space and then the brain
76:24 of works around that that scar that would be an example. And
76:29 , you know, you that scar can't function like nervous tissue. It's
76:33 scar tissue, but it filled up space just like fibrosis does that would
76:38 an example of that, you Well, it was actually in in
76:43 brain tissue. Yeah. You So there's some cognitive stuff that he
76:49 that he struggled with and stuff, for the most part, it worked
76:52 way around that all right now, way that wound healing works in
76:56 So this is what we're looking at kind of the skin, but this
76:59 gonna be throughout the body. This kind of the general thing step one
77:02 whenever you get a cut you're gonna inflammation. That's a natural response.
77:07 like when you get bit by a , that's inflammation is the first
77:10 So what you're doing is you're bringing and sites and you're allowing if there
77:15 a cut blood vessel, you're allowing into the area so that it attracts
77:20 those things that are there to fight and to remove destroyed cells when blood
77:25 into that area, the clotting proteins well as the thrombin sites. The
77:31 cells that are responsible will create a in that area to create a
77:35 So nothing can get in and nothing escape and protect that area while you
77:40 on it. So in this picture kind of this step two is the
77:44 of the clot. So here you the clot and then the immune,
77:47 sites that have kind of migrated What they're doing is like this is
77:50 and destroyed. I'm gonna remove that and clear it all out. Stage
77:55 is when we build new blood vessels angiogenesis and this attracts in fibroblasts and
78:01 types of cells to rebuild the surrounding . And that's what's going on there
78:06 we're gonna see fibroblast migrate in and start laying down new ground work when
78:11 dealing with epithelial tissues. Epithelial tissues pushing in and start working towards one
78:17 to layer over that. And finally final step is okay. now the
78:23 tissue has grown in. You've rebuilt connective tissue, you've repaired those
78:28 You destroy those things you don't need you allow for macrophages and stuff to
78:33 out. Now. Having said all . Let me see here. I
78:37 have two minutes. My young fresh , right? There's one last little
78:45 that I want to cover here. definitions just to make our lives
78:50 Alright, very simple. Everyone say word after me. Apoptosis.
78:57 not apoptosis Apoptosis. Thank you. . Alright, I had a professor
79:03 you said it wrong man, he got angry. All right, So
79:08 apoptosis apoptosis or cell suicide. Cell . Program Cell death. This is
79:12 way that cells are told you're being problem or you shouldn't be here and
79:17 need you to go die in a . And that cell says okay.
79:21 so what it does is it self and destroys itself in an organized manner
79:25 that the materials inside it don't go your body and cause problems.
79:29 so while you're developing between your you all had webs just like
79:35 You don't have them now, do ? Because program Cell death apoptosis occurred
79:40 get rid of those things. That's . We've seen the word autopsy gee
79:44 autopsy gee is how we destroy proteins the body or inside cells to make
79:49 that they don't cause problems to the tautology. These last three terms can
79:53 a little confusing. Atrophy is what did during the pandemic, when you
79:57 around on the sofa and watch youtube day long. Right? Basically.
80:01 is when you don't use something. body is not going to waste energy
80:05 maintain it at its size and so shrinks as a function of disuse.
80:11 hypertrophy is when something grows as a of overuse. Typically when you hear
80:18 and even this other term is Um you're gonna usually hear those associated
80:23 cancer but these can be normal So hypertrophy is when I get over
80:29 . So during puberty your cells were hypertrophic. They were growing and getting
80:35 and then they were dividing massively at accelerated rate. That's hyperplasia. So
80:42 plastic cells are cells that are dividing an accelerated rate. What do we
80:50 tomorrow night at six PM extra credit then test on Thursday. Remember we
80:55 have class on the days of Please don't show
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