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BIOL 2301 Human Anatomy & Physiology I - BIOL2301_lecture07_0614
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00:02 How are you doing today? Let's . There we go. Um,
00:07 got a report that the sound went in the latter part of the video
00:11 . I don't know. So if does remember, I've recorded every video
00:15 every class I've ever taught. So can always go back to previous
00:19 Um, the jokes stay the I mean, it's really that
00:23 So, um, I owe you a graph. Uh, I kept
00:29 an, er, and I couldn't out what it was and I finally
00:31 it was a person who looks like dropped the class, but they're still
00:34 my roster. So it kind of shifting things and I just figured that
00:38 about 30 minutes ago. So I'll that graph up online probably right after
00:42 with an explanation of what grades are why you shouldn't panic. So,
00:47 , that's something to look forward Ok. And then today we're going
00:51 talk about bones. It's like that's today is his bones. Um,
00:58 we're, we're first gonna start with of bone, what bone is,
01:03 know how it's arranged. So we're look kind of deep into compact
01:07 We'll look a little bit, more into uh, spongy bone.
01:10 look at, see how bone is formed where it comes from. And
01:14 what we're gonna do is we're gonna into, um, the actual bones
01:18 the body. And yes, you learn all the bones of the body
01:21 . It's, it's kind of scary you think about it because I think
01:24 like 200 some odd bones. But good news, I mean, when
01:27 hear that number, it's like what have to, yeah, 200
01:31 But like, think about your for example, there's 14 bones in
01:35 fingers and they all have the same and you have two sets of
01:39 So that's 28 bones just right So a lot of these are
01:43 They have the same names like it's a rib, it's a
01:48 So, you know, they're So we'll go through, you'll see
01:53 pattern. It's not as scary or hard as it sounds. The hard
01:57 in, in anatomy. And you're because I don't care, is learning
02:01 names of all the muscles. So are, if you're going into physical
02:06 and stuff, knowing all the muscles important, becoming a nurse, I
02:10 know, it doesn't seem to be important, you know. So we'll
02:14 kind of understand the nomenclature when we the muscles, but we won't have
02:17 name all 600 muscles in your And I do have colleagues around the
02:26 that teach all the muscles. I bad for their students. All
02:33 So what I want to start here is I wanna look at some of
02:36 features or characteristics that each bone All right. So there's markings.
02:40 when you pick up a bone and at a bone, what you're gonna
02:43 , especially if you're doing the they're gonna sit there and say,
02:45 your landmarks, learn the different characteristics each of these bones that you can
02:50 them. All right. And that's not the important part here.
02:54 question is why are these landmarks actually ? What, what, what purpose
02:58 they serve? And so we have types, we have depressions, openings
03:02 projections, that's kind of the big . And then each of these have
03:06 names. And so you'll come across like fossa, you'll come to learn
03:10 just remember, you know, we're to see fossor in just a
03:14 But what these are, these depressions where are allow one of something to
03:19 , right? So first, you have a, a place where a
03:22 meets another bone. All right. so this is a way that these
03:26 bones can interact. So they're not and sliding over each other in inappropriate
03:32 . All right. So that would one example of a depression, but
03:36 type of depression might be where a vessel or a nerve travels. And
03:40 like on the rib, for you're gonna see, um again,
03:44 probably in this class, but more the lab, you'll see this depression
03:48 this facet uh is where the nerve the blood vessel travel alongside the
03:55 right? And so that's why it's . So it creates a divot for
03:58 things to happen. And then the thing is this articulation. So at
04:03 joint where you can get these two to slide against each other in
04:06 in a, in a, in manner that allows them to actually create
04:10 sort of force. That's another place you're gonna see a depression. So
04:14 now, the names aren't so right? If you were at community
04:20 , what do you think they'd make , do you think they'd make you
04:22 these? Yeah, they would. . I want you to start learning
04:27 as you come across them and understand they mean. Ok. Because I'm
04:32 just point to things I'm gonna say is an eon and then you're gonna
04:35 , OK. Well, I remember eon is a projection. What is
04:38 purpose of that projection, that sort thing? Ok. That's kind of
04:41 we're going. So these are kind depressions, kind of a stupid
04:48 We have a couple of different types openings, openings are called holes,
04:52 know. Right. They're basically things things pass through. What type of
04:55 are gonna be passing through, primarily vessels and nerves. All right.
04:59 we're gonna see some major ones. the, the key one that you're
05:02 see here is a, the other is gonna be a and if there
05:06 many of them are called for all right. So the big hole
05:11 your, uh in your skull, we're gonna see here in a couple
05:14 minutes is called the Forman Magnus. do you think for? And Magnus
05:19 framing is whole. So what do think Magnus big? It's the big
05:26 . That's, that's what they called . So just because they use Latin
05:31 make it sound fancy, doesn't mean it's something fancy. It's really a
05:35 . All right, fissures are another . So here you can see in
05:38 frontal bone, here is the super frame and you'll notice that the name
05:42 you everything about it sura above that's that cavity. And then,
05:50 it's above the, the eye cavity whole. Excuse me. That's just
05:55 example. All right. And then all sorts of different types of uh
05:59 . So again, here's a whole of different types of projections. They
06:02 fun names like tubercle, tubercle is a fun word to say. So
06:06 try it, tubercle, anything with at the end sounds fun,
06:10 Tuber coal. But you got crass epics, you have processing spines per
06:16 . Do these words sound like things poke out, that stick up and
06:20 do and, and in essence, are places where muscles are going to
06:23 attached, where tendons are gonna attach ligaments and they have all different types
06:28 shapes and those shapes. Um, words that you see are descriptive of
06:32 shape. So when you look at scapula, for example, we're going
06:35 see the spine. And when you of spine, what do you think
06:39 something you elongate that sticks up, ? Like like a bunch of
06:44 create a spine, the spine of world type type of stuff. And
06:50 really, when you're looking at the , it should kind of uh jog
06:54 in you that says, oh this is a descriptive word to help
06:57 better understand what this thing sticking up like. All right. So when
07:04 see these things, understand that they're to help you understand the purpose of
07:09 bone, not so much, just , oh, now I know what
07:11 bone this is because trust me, gonna be able to tell the difference
07:15 most of these bones. You when you go in the lab,
07:18 pick up a humorous and you'll be to tell the difference between a humorous
07:21 a femur that, that's pretty you know, one's like this one's
07:25 this. All right. Now, the bone. We have marrow and
07:33 two different types of marrow. We red marrow and yellow marrow, red
07:38 in this picture right here, it's . You have to look better is
07:42 on the side. You can see red on the outside. Then there's
07:45 yellow area on the inside. This on the outside is the red
07:49 This is what we refer to as hemopoietic or hematopoietic. Either of those
07:53 terms are co correct. I learned as amato poetic, but they got
07:57 of the ato in the middle and just call it hemopoietic. All
08:00 Now, this type of tissue, you see the word hematopoietic, this
08:04 a tissue that produces blood cells, ? That's what that term means.
08:10 poetic or hemopoietic. So we're it doesn't matter if we're talking erythrocytes
08:14 white blood cells. But just you're producing red blood cells far more
08:19 you're producing white blood cells. So why it has this reddish appearance right
08:24 where this stuff is located, depends what age you are. When we
08:28 looking for it in adults, the red marrow is very limited to where
08:34 actually located. It's very difficult to or I shouldn't say difficult to
08:38 It is difficult to reach. That's a better term. All right,
08:42 find it in the ends of the bone. So where the spongy bone
08:45 in the long bones and the, um, epithets. That's where you'll
08:50 red bone marrow. You'll find it in the of your flat bones.
08:56 your flat bones would be like your , your hip bones. And so
09:00 can imagine if you're a bone marrow , you have to go into some
09:05 horrible places to get that stuff. . Because it's, it's not easy
09:10 get to those places. All But kids, Children have red bone
09:15 everywhere because they're in this constant state growth and they're constantly producing red blood
09:21 as they're growing. So you could cut in any sort of bone and
09:24 even find it in the med So those elongate cavities in the diathesis
09:29 filled with red marrow as a as child. So there it's easy to
09:34 to. Now when you age, happens is is that this marrow here
09:40 the medullary cavity gets replaced by that marrow in adults. So this is
09:47 I say the older you get, more fat you get right? Because
09:51 actually there inside the bones as you're . Now, what this is is
09:57 adipocyte. So it is truly a . But if your body gets in
10:02 state where it's in desperate need for blood cells, what will happen is
10:07 red blood cells in the red marrow begin amping up and those stem cells
10:12 will start moving around into the yellow and start replacing that yellow marrow with
10:18 red marrow again. All right. it's not like you, you lose
10:23 yellow or that red marrow. It's that you don't need to produce as
10:26 red blood cells as kids do. so that's kind of the difference.
10:30 as you get bigger, you primarily with yellow, with the exception of
10:36 places, I describe the hard, hard to reach places, but then
10:40 can revert if you need to. whenever we talk about a tissue,
10:47 we're really today is kind of tissue and organ day because you don't think
10:51 bones as being an organ, but are an organ and bones if it's
10:55 organ are derived from tissues and the of tissues we're dealing with here is
10:59 tissue. All right, that's just fancy word for saying bone, the
11:03 as opposed to bone, the right? That ose tissue, remember
11:08 are made up of groups of similar . And so in this case,
11:13 dealing with the connective tissue that's primarily , but that means there's still cells
11:17 that are responsible for those cells. so what I wanna do is I
11:20 to first focus on those cells, we'll talk about the tissue and then
11:24 when we'll jump on to the organs memorize all our 200 some odd
11:30 OK. So there are four major types that are found in osseous tissue
11:35 they're enlisted here, Osteoclast, which not related to the other three.
11:39 then the other three are related. start with the osteogenic cell which can
11:43 the osteoblast which then will mature and the osteocyte. All right. So
11:49 we see blast at the end of world, what does it mean?
11:51 you guys remember immature? And then we have sight, it means
11:55 right? And whenever you see osteo when you ever see genic or
12:00 it's, it's referring to the stem of that line. It's not a
12:05 cell that can become anything, it's for this particular line. All
12:09 So we want to start with the cells. All right. So the
12:12 one, the one that's kind of as a stem cell is that
12:16 it's mitotic, it sits around and basically replicates and keeps a population of
12:22 cells around. But it gives rise those osteoblasts right now where we find
12:28 . If you recall, we said have that compact bone and we have
12:32 spongy bone inside and surrounding the compact on the outside is that periosteum and
12:38 basically connective tissue, but right next the bone, that's where we're gonna
12:43 this living layer of cells. So gonna find those osteopro cells there in
12:48 periosteum and then inside the, the itself where the lattice of the spongy
12:53 is, you're gonna find them there well in that endosteum. All
12:59 So this is where they're gonna be . But because their job is to
13:03 osteoblasts, you'd expect to find osteoblasts as well. Right. And you
13:08 . So there's osteoblasts as well found the periosteum and the endosteum. So
13:14 can see here where we are here the cells that have differentiated.
13:18 here's the osteogenic cell, what they're is some of these are staying behind
13:23 what they're doing is they're producing these cells that are going to become
13:27 So now they're being labeled here as . Osteoblasts are immature cells. Their
13:32 is to produce matrix. And so what they do is they start laying
13:37 matrix, they lay down matrix below . And then what happens is,
13:41 as they start releasing this matrix, actually they start pushing up and some
13:46 them get trapped inside their own right? So the bone is being
13:53 because of those osteoblasts. And then happens? They get trapped inside their
13:58 matrix and then now they differentiate and , OK, I'm no longer going
14:03 make matrix. I'm going to maintain matrix, make sure the matrix is
14:08 . So it's doing the job that was built to do. So that's
14:12 the osteocyte does. It can't make new bone, they just hang out
14:17 the bone matrix that they created, very much alive. They have uh
14:23 kind of these um extensions from their that go out and touch other osteo
14:30 or sorry osteocyte. So they actually to each other and they detect the
14:36 inside the bone to make sure that bone is resilient enough to do its
14:42 . So for example, when you , every time you take a
14:45 that bone has to bear the entire of your body. And that tension
14:50 felt in the bone and the osteo sites can detect whether or not it's
14:56 appropriately to that degree of stress. kind of cool. And so they
15:02 to rearrange the matrix, make sure it's uh being maintained. So those
15:09 the three osteogenic cells, osteoblast makes osteocyte maintains it. Osteopro geor is
15:14 stem cell pretty straightforward, right? far, so good. Then we
15:20 the osteoclast. Now, these are unrelated, but they still work on
15:25 bone. If the osteoblast is responsible , for building bone, the osteoclast
15:31 responsible for breaking down bone. All . So, wait a second,
15:36 would I wanna break down my Well, if your bone has been
15:41 down inappropriately, I want to break apart. So it's no longer doing
15:46 inappropriate work. And what I wanna is I want to rebuild it so
15:50 it does the work that it All right. Now, they come
15:53 a different line of uh progenitors and they do. I love kind of
15:56 picture, it kind of like looks this, this line that sits there
16:01 you know, it grinds everything But in essence, it's kind of
16:04 it is. It basically breaks the down and weakens bone in different areas
16:08 it releases that calcium phosphate which makes the matrix so that the osteoblast can
16:13 that stuff up and redesign and rebuild bone so that it works. All
16:18 . So this process is called All right. So the matrix is
16:24 built by osteoblasts, but the osteoclasts resorb the bone. And this is
16:33 best picture I could find that kind shows it goes through the process.
16:36 can pick any point where you wanna . All right, we're gonna start
16:40 here in this top corner. All . And what this shows is the
16:44 of absorption of bone. And so know this is kind of look like
16:48 Inky Blinky and Clyde, you know those are? Right? Oh My
16:55 , you guys are young. Those the three of the four ghosts in
17:03 . Do you see them now? BK Blinky and Clyde. I think
17:08 pinkies in there also, but Clyde the fun one. All right.
17:12 here you come along. So here can see that the matrix is,
17:16 has some sort of weakness in All right. Now, obviously,
17:20 our case, the weakness was formed the osteoclast here. But let's just
17:23 we're here on a uh a spongy , we can see that the matrix
17:27 doing its job, it's not properly . So the osteoblasts migrate into the
17:32 . And what they do is they down osteoid, that osteoid there reinforces
17:38 bone and allows it to deal with stress that this lattice right here is
17:44 for addressing, right. And once lay it down off, they go
17:48 they travel off to wherever they need , to find the next bone that
17:51 to be done. Uh But your no longer needs this one. You're
17:55 applying that stress anymore, or your needs to release calcium for other
18:00 So this is when an osteoclast comes , breaks down the bone where
18:05 it's OK to break it down and release those calcium phosphates and stuff,
18:10 calcium and the phosphate and the uh material. And now that stuff can
18:15 used by the body for other And it's like, oh no,
18:18 we have stress again. So we keep rebuilding bone. Now, this
18:24 kind of a, a simple model . But I want, I want
18:28 point out just take your daily What you've been going through about 5
18:34 7% of your bone mass is recycled week. All right. So if
18:39 want to put that in perspective, get that up to 100% that would
18:42 20 weeks, right. So every weeks, your body remodels the equivalent
18:48 your entire skeleton. That means twice year, you rebuild your skeleton almost
18:55 times a year. Isn't that So, this is not, not
19:00 tissue. This is very much a tissue. It is very active
19:04 If you think about what you're doing . Right? And so what we're
19:10 when we break it down is we're calcium available and you're gonna find out
19:15 is one of these uh these uh that is ridiculously important in your body
19:22 . We don't pay it much right? It's how your muscles
19:26 It's, I mean, smooth it's as well as your skeletal
19:30 It's how cells communicate with each It's responsible for all sorts of
19:34 And one of the purposes here of bone is to store up calcium for
19:39 you need it. It makes your strong, but it's also about a
19:44 other jobs. So you guys kind get the picture here. What's going
19:49 ? Osteoblast, break things down, , make or build things up.
19:54 , break things down and it's not . It's based upon need of the
19:59 . So if the bone has need building up uh strength, then what
20:04 gonna do, it's gonna build along stress lines. If it sees something
20:08 no longer is needed or is unused it doesn't meet the needs of the
20:12 , it will break that down and where the remodeling takes place so
20:18 So good. Yeah. Yeah. strong. Mhm. It's gonna
20:27 it's gonna be breaking down and it's gonna be like, don't think of
20:30 as I'm breaking down the bone, breaking down little itsy bitsy portions of
20:34 bone that are no longer used. gonna learn here in just a
20:37 Something called wolf's law. All I'm just gonna say it now because
20:40 law is easy. It's one of , one of the easy physiological laws
20:44 you can memorize. Wolf's law basically your bones are gonna be as strong
20:48 you need them to be. That's it says, right? So your
20:53 as you use them will become stronger upon your need. It's kind of
20:58 my muscles will be as strong as need them to be in order to
21:01 the function. So what do I ? I go and work out?
21:05 my muscles will grow until they no need to grow any further.
21:10 there's a limit to how big muscles get. There's also the truth.
21:15 also, there's a, there's a to how big your bones can
21:18 But let's paint this scenario if all do is sit on the sofa all
21:22 long and you never get up and to go to the bathroom to the
21:26 , do you need strong bones? . All right. No. So
21:31 body doesn't waste the time and the building bone to do some sort of
21:35 activity that you're never going to Instead if you run and exercise,
21:41 mean, you don't even have to . If you get up and walk
21:43 and do things and lift things and things, move your body, then
21:49 putting stresses on the bone and the responds by building the bone stronger.
21:56 . That's the idea of wolf's It builds the bones to fight the
22:01 that it normally has to deal with that makes sense. So every time
22:05 take a step, you're putting that weight of your body on that bone
22:09 that bone receives the stress and so structures and strengthens the bone so that
22:14 can respond to that if that makes . Yeah. OK. It's not
22:20 to say, hey, how many are you gonna lift the two ton
22:24 ? You know, that's, that's of the realm of what the bones
22:29 . All right. So what is bone? What, what is it
22:32 up of? Right. Well, , there's different aspects to the
22:37 all right. And so what we're in this little picture here is we're
22:41 at the mo molecule level and then kind of working up to the fiber
22:46 and then from the fiber level, actually building structure within our actual
22:51 So just to kind of give you sense of this would be the outside
22:54 the bone. This would be the cavity of a long bone. All
22:58 . So we're looking at a slice a pie taken from a bone is
23:02 of what you're looking at, And this is a long bone where
23:05 I took a cross section through it I was looking at it this
23:08 you're kind of looking at that top . All right. So you can
23:13 here here's compact bone, compact compact bone comes up to here and
23:16 you have this lattice work that spongy and then everything over here would be
23:21 cavity. So you kind of kind envision that. All right. So
23:27 you're looking at bone, it has an organic component and an inorganic
23:34 right? Organic, what does that ? Well, these are the
23:39 these are things the biomolecules. And we're talking about collagen, which is
23:43 protein. And you can see over this is what collagen looks like.
23:47 then you take those strands and you them with other strands. So you
23:49 these really, really tough uh troo . He he so you can see
23:54 is a rope like structure and then take all these things and you bundle
23:57 together. So you get this big bundle and so these are the fibers
24:02 make up a bone. And then we're gonna do is there are gonna
24:07 cells that are gonna be uh responsible this or around this. And so
24:11 gonna deal with the cells in just moment, but ultimately, this
24:17 this collagen in this arrangement is what the bone its strength. You can't
24:25 it, you can't stretch it. It's, it's just really, really
24:30 and really, really rigid because of arrangement of fibers. Now by itself
24:37 that's resistant to stretching and twisting, still not hard. This is where
24:44 inorganic comes in. So we're gonna in these crystals, these salts,
24:49 called a uh appetite crystals. A T I T E aetate appetite,
24:55 it's calcium phosphate is what it So it's salt and so basically what
25:00 doing is you're preserving these fibers in uh uh uh salts and that makes
25:07 matrix rigid. So, whereas collagen , I mean, like like in
25:15 is mobile, I'm just gonna play my nose for a little bit,
25:19 ? That's cartilage. It moves around fine. But if I get up
25:22 to the top where it's bone, doesn't move. That's just my skin
25:26 on top of the bone. When break your nose, what you're doing
25:30 you're just breaking that bone up right? You're not breaking the
25:35 Cartilage is bendy, right? What doing is you're ripping and tearing those
25:44 that I've hardened in their nature, ? So this is what gives it
25:50 and inflexibility. Um, they just them. All right. So I
26:01 talk about, uh Taylor Lawrence uh Joe Theismann here. But I
26:05 I've probably outage you guys at this . So you probably don't know who
26:10 of those two people are. Yeah. So we won't talk about
26:15 . All right. So here we again. And we're looking right.
26:20 here's your compact bone, compact bone then here in the middle, there's
26:24 matrix. So we're doing that slice a bone again. And you can
26:28 we got these really weird ring looking . These are called osteon. The
26:36 is the structural unit of a compact . So again, I want you
26:40 think in perspective, we're looking at long bone and we've made a slice
26:45 the diathesis and you can see through slice that you have a series of
26:50 that are repeated over and over and again. And if you look at
26:54 , they kind of look like a eye, right? So there's like
26:56 outer rings and middle ring and inner . And then there's this like hollow
26:59 point in the middle, you kind see this here. So there's the
27:04 kind of represent the boundaries between the in this picture right up there.
27:10 right, if you look here, can see the dots and they're trying
27:13 show you there's the ring, there's ring, so on so forth so
27:16 can, you can, you can what we're talking about. We're talking
27:19 the osteon. All right. when we say this is a structural
27:24 , what we've done here is we've these osteoblasts and they've been growing the
27:30 , they're laying down matrix that creates different rings. And these little dots
27:38 where those osteoblasts got trapped. And that's where they exist now. So
27:43 are osteocyte inside those little tiny black . OK. So your bone has
27:51 cells inside them stuck in these Now, you can see when we
27:57 one of these things out what it like. We have uh an inner
28:02 , a middle ring, another ring then there's another ring around it and
28:04 just these series of, of And if you look, the fibers
28:09 being represented by these lines and the go one direction and then they go
28:14 other direction and the next one, go the other direction. And what
28:16 done here is you've created a pillar has a series of fibers that are
28:22 themselves as they move further and further . So if one fiber is going
28:26 way and one is going that basically, they're, they're moving in
28:29 direction. So the torsion or torque you would apply to it is going
28:33 be resisted because of the different directions the fibers, right? When you're
28:39 kid and you're doing paper mache you , you put one fiber down this
28:43 and then you put another one like . All right, I'm probably missing
28:49 spot on that one because you probably remember playing with paper mache. You
28:54 that plywood is particularly tough. Have played with plywood? Right? P
28:59 is basically wood fibers which were all in the same direction and then you
29:03 it all up and you throw it and you give it some glue.
29:06 now the fibers are going different If you can get more strength out
29:09 a thinner board of plywood than you with a normal cut piece of wood
29:15 the fibers are going in opposite they reinforce themselves in very different
29:22 And so these pillars which are hundreds and hundreds and hundreds of times
29:29 the compact bone are there to give resistance and the strength to the
29:36 So it's not just that the presence the fiber is there, it's their
29:39 as well. So if we take closer look at an osteon, so
29:49 , here we are right, here's osteon, we've pulled it out.
29:53 looking at, we can see the going in opposite directions. And what
29:56 gonna do is we're now just kind focusing in with all the different rings
30:01 of smashed together. Now, we see there is a unique arrangement in
30:06 . And again, I know this cartoon, here's an electron micrograph.
30:09 a microscopic view of the same All right. And what you can
30:13 is that in the middle of every , there's this big giant gaping hole
30:17 contains a nerve fiber, an artery a vein. So where you have
30:23 and veins traveling, that means you're moving blood between two points. All
30:29 . So this central area is called central canal. See how clever that
30:34 . So there's lots and lots of canals. The central canal is not
30:38 medullary cavity that's way over here, ? It's within this little tiny
30:43 So there's a central canal. All . And then each of these rings
30:49 referred to as concentric Lamela, So Lamela is the name of the
30:55 because it's round in nature, it's to as being concentric. OK.
31:01 where the name comes from. And you have multiple concentric rings, multiple
31:06 Elli. All right. And that's the fibers are going in opposite directions
31:12 the boundaries of the la. So can see right there, they look
31:16 these weird, strange looking eye maybe little alien looking things. Those
31:21 the osteocyte, those were the cells got trapped and are now responsible for
31:26 out the matrix and determining whether or they're, it's doing its job as
31:31 terms of resisting stress and torsion. right, they live inside a little
31:36 space called a lacuna. Apart from Mata what does lacuna sound like?
31:47 word comes to mind when you hear . What's that lagoon? That's exactly
31:54 word I'm looking for. They exist a pool of fluid that surrounds
32:01 It's like a little mini lake and fluid has a lot of calcium
32:05 it has a lot of phosphate in . And what they do is they
32:09 , they can add and subtract the to and from their immediate surrounding
32:15 And this kind of serves as a to be able to say, oh
32:18 , what we need a little bit calcium. Ok? Well, instead
32:21 waiting for you to go consume milk spinach, um I will loan you
32:24 little bit of calcium. So it you to manage calcium um production and
32:32 in this little entirely environment. But can just think of it. The
32:36 or the lacuna is where the osteocyte between the lay the rings that they
32:44 down when they are osteoblasts. And finally, we have these little
32:50 extensions of the osteoblast and they move each aid osteoblast osteocyte. And this
32:58 the osteocyte to talk to each but there's a little tiny canal through
33:03 that little extension goes and we call little tiny canals Nili. All
33:10 So the exists between these and it's easy to see. I'm obviously one
33:15 these pictures right here, but you see how they kind of extend
33:19 Right. And here you can see these are little tiny lakes, little
33:23 lagoons and that's how I remember. right, so far, are you
33:29 me, with the structure? what's a lacuna, the place where
33:33 osteocyte lives? What's the place where extensions are? What's a, it's
33:40 ring? All right. Now, central canal goes up and down.
33:46 right. In order to get the vessels in the nerves, there,
33:49 has to be something that penetrates through bone so that it then goes up
33:53 down through the osteon. All And so we have a name for
33:57 and you can see them right They go in and then you're going
33:59 and down here we go. Those called perforating canals, right? So
34:04 got a central canal, the way get to the central canals, you
34:06 to the perforating canal. All So they're right angles. So central
34:11 go up. So there's tons and of central canals and there's perforating canals
34:15 allow that to happen. And then the outside of the bone. Remember
34:20 here, you can see here. that structure right here called this thing
34:24 we're tearing away periosteum? Good. heard it. So, periosteum,
34:29 on this side? End? All right. And we said there
34:33 layer living cells underneath the connective tissue the periosteum, right nearest the
34:40 And those cells remember are osteopro and osteoblasts and osteoblasts, their job is
34:45 lay bone, right? They're putting bone. And so what happens is
34:50 they're putting down bone, they're creating own giant LALI and they are found
34:56 the outside edge of the bone. when you think about a circle and
35:03 distance around a circle, what do call that circumference? So it is
35:08 the circumferential la. And you'll see we have circumferential Elli on the inside
35:16 well. All right. OK. , how do we distinguish them?
35:20 , one is external, one is . So we have the external
35:26 see going all the way around, the way around. And then over
35:32 we have this network of LALI going the way around. That would be
35:36 internal circumferential lamel. All right. that's how we define the boundaries of
35:45 compact bone and it's being laid by osteoblasts that are found in the
35:53 And on the end stum now, you had a bunch of straws in
36:00 hand, straws are perfectly round, I could say dolls, but you
36:04 , I don't know what a doll , right? But if you had
36:07 , I'll just pull up one of pins. So if I grab his
36:11 and put them together and they didn't these little things. Would there be
36:15 bitty spaces in between each of these structures? Yeah. So your bones
36:20 have a lot of hollow space, is not a good idea.
36:23 Because if you had hollow space in bones, what would happen?
36:26 they would, they would, they lack the strength. So, in
36:33 all these round is the space that to be filled up. And so
36:39 as your bones are being developed are those spaces and they fill them up
36:44 bone. And we refer to this the interstitial. So whenever you see
36:51 word interstitial or inter, it means stuff inside or between. So
36:59 el these are the lay of the and then the stuff in between are
37:06 interstitial Elli. All right. And these are either laid down or what
37:14 happen is, is like, well, this osteon isn't doing its
37:17 . So, what I'm gonna do I'm gonna break it all down and
37:20 gonna rebuild an osteon. And so this might be remnants of an old
37:25 that was destroyed. And where as new osteon came up in around
37:30 that kind of makes sense. So compact bone is compact because all the
37:36 is filled with bone material with All right, or osteoid is the
37:42 term here. So, do we structurally what's there? So, what's
37:48 osteon? What's in the center let's start this, what's in the
37:52 of an, you can look at picture, I'm not central canal,
37:59 ? And then what are these? are a series of starts an L
38:06 . All right. What's at the of all the Lomeli, one of
38:12 little black dots osteocyte. And what they live in? Lacuna? And
38:18 they talk to each other via And then how do I get those
38:24 blood cells or not blood cells, uh blood vessels in the nerve up
38:28 the uh central canal, perforating And then the thing that makes up
38:35 boundary of the bone is called the . One on the outside is
38:41 the one on the inside. Good. See, and then the
38:44 in between is interstitial. If you the information in a way that makes
38:51 to you, this is what makes to me, makes sense to you
38:54 it out easy. Peasy. Spongy bone is arranged like a
39:03 It doesn't have these osteon instead of of this open lattice work. What
39:08 refer to this lattice work as our . If you ever watched Jeopardy,
39:15 have Alex Trebek tribe, I don't , help, right? But
39:21 it's just these, these, these of bone that kind of look like
39:25 osteon. You can see they have series of there's just no central
39:30 right? You just have la there's osteocyte stuck in lacuna. These
39:34 lacuna have that go to the to outer la and so they can get
39:40 nutrients from the surrounding environment. So don't have to have blood uh uh
39:46 through osteon to them. And so can imagine if this is a,
39:49 is a cutaway through one of those and these are built along stress
39:57 So this is where the primary work breaking down bone is actually taking
40:02 It can take place in compact but you don't do so quite as
40:08 . But this is where you would it because a bone needs to be
40:12 and modified as you use it. right. So we refer to these
40:18 parallel cause reasons, no blood And then you can see if you
40:27 at the picture probably over there, can see there's a little tiny dots
40:30 are representing the conic open to the . All right, same sorts of
40:39 , different names, different structure. . And these are again built along
40:46 lines. So while it looks remember what I have is I have
40:50 that are detecting the degree of stress that bone structure. And so it's
40:54 no, no, we gotta build this direction. So that's what the
41:04 is. All right, how we these tissues is through a process called
41:10 or osteogenesis. All right. And , most of these words, you
41:16 probably figure out if you had just little bit of time to think about
41:20 . All right. Now, this very early on during embryogenesis,
41:26 So as you're developing, you, start off uh building bone very early
41:33 and it's gonna use one of two , what is called intramembranous ossification or
41:40 ossification. All right. Now, switching the slide was intramembranous mean,
41:50 by itself intra inside and then inside membrane. OK. And what do
41:55 think endo inside and then control All right. So here, what
42:04 gonna see is that we're gonna just just start developing bone within a structure
42:11 it's just gonna naturally start forming. right. But here we're gonna have
42:17 cartilage first and we're gonna replace the with the bone. That's all those
42:22 things mean. All right. So begins very early on. It continues
42:29 through childhood and it will continue on adulthood right now. You are going
42:34 endochondral bone development and you don't even it. All right. And it's
42:40 because you guys are young. It's , it will keep happening until you're
42:43 40 years old. All right, gonna see. We have a,
42:47 bone here called the Zoid Process. Zoid pro process remains cartilage for a
42:53 long time. It's like when you in your late thirties or forties,
42:57 actually becomes solid bone. This is weird, right? So we'll get
43:04 that in just a second. All , we're gonna start here with the
43:11 , remember? All right, now , I understand that none of you
43:17 taken developmental biology, right? Anyone am I am I wrong? One
43:23 , two people. All right. they talk about the development of the
43:27 very early on from the? So the stuff like that? No,
43:32 of just like words that sound So sounds, sounds familiar, doesn't
43:36 ? Right. So what we're dealing here, um and I'm really excited
43:40 now I've got two people who may understand some of the words I'm gonna
43:42 . All right. So we are is called a Trib blastic organism.
43:45 right, we start off single multiple cells, the cells divide into
43:49 different groups of tissue, right? that's endometrium, sorry, not
43:54 excuse me, but backup, backup is reproductive. Um What is
44:00 What is mesoderm? And what is and a lack of a better
44:05 Ectoderm are things on the surface. is um uh structures that are um
44:14 like the organ tissues. And then mesoderm, which is anything that's kind
44:19 red in the body is the way always remember it, right? But
44:21 I wanna focus here is on the . All right. So again,
44:25 don't need to know these three please, please don't sit there and
44:28 down it's mesoderm and I must know , right. One of the things
44:31 mesoderm gives rise to is the All right. And the meeny is
44:38 gives rise to these different types of tissues that we've described. And so
44:43 represents this loose uh uh tissue that can be differentiated in a whole bunch
44:49 different things. And so you can here, we got these Mazal
44:54 there's fibers. So you can see a network of material there. And
44:57 happens is that some of these cells going to differentiate and they become
45:03 meaning they're going to produce bone. so they're kind of together, they've
45:08 , they're creating these osteoblasts and what osteoblasts do? They start laying down
45:12 ? And so they're laying down matrix it goes on all different sides.
45:16 you can imagine um here, the of us were uh osteoblasts and you're
45:21 down matrix, you're laying down matrix I'm laying down matrix. And what
45:24 start doing is we start pushing each away, right? Because I'm laying
45:28 in all different directions. But then there's gonna be a point where I
45:31 lay anymore and they can't lay And so I trap myself inside this
45:36 , right? And so there you see, I've got an osteoblast that
45:40 now trapped and it's going to become osteocyte. And then what happens is
45:45 matrix? Remember we said the matrix is primarily collagen starts getting salts.
45:51 so part of building this matrix is these salts to it. And so
45:55 is what traps those osteocyte, but what's on the outside blasts,
46:01 They're still there. And so what doing is I'm still laying down matrix
46:04 dividing and I'm pushing this out. so I begin creating this structure of
46:11 where I've got things that are but I still have cells on the
46:14 . And I'm laying down a network looks an awful lot, lot,
46:18 that, that an awful lot like bone. Doesn't that kind of look
46:22 spongy bone? Now, it's not bone yet. It's doesn't have that
46:26 . But this is this woven bone what's happening because all I'm doing is
46:33 just started just laying down matrix and building and pushing the mesen outward and
46:41 away from this point of origin. at how the mesen is being compressed
46:48 pushed away on either side in the cartoon. And so now I have
46:54 osteo progenitor cells and I have osteoblasts are kind of getting stuck against that
47:01 . I've got cells that are stuck the network. I've got cells that
47:05 stuck in the matrix and now what doing is they're starting to behave and
47:11 bone that we're more familiar with. while this looks like spongy bone and
47:16 got blood vessels penetrating in and providing and stuff, what happens is these
47:21 on the outside, begin to start bone like. So, so I
47:26 up with a layer of compact Now, what do you think this
47:31 out here? It's connected tissue. the name of it on the outside
47:37 a bone periosteum. So that meeny to compress and compress, compress and
47:47 that periosteum on the outside. And I've got osteoblasts that are laying down
47:53 bone. I got osteoblasts and some gender cells here maintaining the lay of
48:01 spongy bone, which started off in less organized manner and on the outside
48:07 , on this side, periosteum, osteoblasts. So this is how I
48:13 this layer of compact bone that protects inner spongy bone does that kind of
48:22 sense. So there's nothing on which building. It's just I'm starting inside
48:29 matrix of tissue and I just start stuff and it arranges itself naturally,
48:36 because it has a model, but cells just kind of get trapped and
48:41 just do what they do as they're to do that kind of makes
48:48 All right. So that's how we intramembranous growth. I'm inside a
48:55 I build these structures and it gives to the shape that I'm familiar
48:59 Compact bone Oreo, right? It's compact bone Oreo with spongy bone on
49:05 inside. Endochondral begins when we build this cartilage skeleton. So here we're
49:18 a uh uh a developing embryo, not an embryo at this point,
49:22 ? A developing child where it has cartilage skeleton. That's what you're seeing
49:30 . It's been stained. So you see where the skeleton is at
49:34 right. And then what happens is that, that, that cartilage
49:40 to have calcium laid on top of . And so what we're doing is
49:45 osteogenic cells are starting to lay car lay calcium down, which causes the
49:52 on the inside to be denied access their nutrients. So, when the
49:58 is denied as nutrients, what does do? He dies? Right.
50:04 I don't give you your food, gonna happen to you besides getting
50:09 you're gonna die, right? It take a little bit of time,
50:12 these are really, really active So think about being a teenager and
50:15 denied a single meal. How horrible was, right. That's kind of
50:18 going on here. They're like, we're gonna die. And so they
50:21 and so these cells begin to And so what happens is, is
50:26 progenitor cells start migrating into the area they take these cells that have died
50:31 replace them with these osteopor genetic cells they start laying down matrix and then
50:37 you end up with are these areas are going through this process of
50:42 So you can see here, here's diaphysis would start off as cartilage and
50:48 a small collar of bone, ultimately completely replaced by a bone. And
50:54 down here in the epithets as blood penetrate through, we're gonna see the
50:58 process occur. The cells are being access to uh their blood. So
51:04 die off and you replace them with this osteogenic tissue which then starts laying
51:09 bone. And what we end up is these areas at the end,
51:13 epithets having bone. And again, gonna be the same sort of
51:17 I'm gonna put compact bone on the because I'm being pressed outward and I've
51:22 spongy bone on the inside. All . And so this is kind of
51:26 we, where we end up when uh very, very young. So
51:30 is when we're born roughly. Now we are just pre toddler.
51:34 so we have areas of primarily but bone is starting to replace
51:38 And then the central part of the is bone tissue, osseous tissue.
51:44 , you heard me say a couple days ago, my horrible um truth
51:49 my Children and how we just kind ignore them and let them free range
51:52 fall off stuff and why? Because are primarily made of cartilage, they're
51:58 and they bounce. You don't like idea, but they do. I
52:03 , I watch when, before I a kid, I watched one of
52:07 friends', kids literally tumble down an step stairway. And the little
52:13 it was a little girl, she, you know, she's a
52:16 like younger than this, right? mean, we're talking a little bit
52:18 than that and she looked up and mom wasn't there. So she was
52:23 , I don't know if I'm supposed cry or not. And her dad
52:25 at her and said, who's who's tough as nails? Hannah.
52:31 she got up and walked away and right. We do the same thing
52:40 looking for the, the pity response mama. So, in our
52:44 that's what we do. No, pity. Just get up, dust
52:48 off. Move on three days broken wrist, it wasn't a big
52:55 wrist. One had to wear a . All right. So again,
52:59 can start seeing here as you get , the epithets gets stronger. The
53:05 is now starting to hollow out and starting to fill out that med
53:09 But notice what we have here is region of cartilage that sits between the
53:15 and the Diapy. Remember we call region the metaphysis, it contains what
53:19 called the epithelial plate. And the plate is where you have actively dividing
53:27 . All right, and is actively . Cartilage is what allows you to
53:32 upward. So your long bones are themselves to expand because this area still
53:42 dividing cells that are pushing the epithet from the diaphysis on both ends.
53:47 your bone is getting longer and longer longer this way. At some
53:53 you're gonna go through puberty somewhere between ages of 10 and 25 the bone
53:59 in the diaphysis is going to grow than the cartilage dividing in the e
54:04 plate and it will begin replacing those cells. And ultimately, it will
54:10 up to the front end of those . And when it does, you're
54:15 growing. So this happens differently for people. Some are late and will
54:22 to grow until they're in their Some of you stop growing when you're
54:27 to the age of 10. My daughter was so sad when she
54:32 out that she wasn't getting any you know, she's 16 and she
54:37 , she hit, she got her Burt and then she just kind of
54:41 , right? My two younger sons are four years younger than her have
54:46 caught up with her. And she's like, I don't wanna be
54:49 she's not that short, but she's relative to her brothers. So this
54:58 of growth where we're talking about the um epithelial or sorry, not
55:04 epithelial, the epithelial plate. This of growth is what is called interstitial
55:10 growth within the bone. All And so what's happening here is the
55:16 that's nearest, the epiphysis has the cells. And what they're doing is
55:22 laying cells downwards. In other they're growing, they're pushing this way
55:28 laying cells that way, right? , I'm pushing downward. So I'm
55:33 further and further away from the So I'm laying down cells driving this
55:38 and this is why this gets bigger bigger and bigger. But we also
55:42 osteogenic cells. And so the osteogenic are progressing upward and they're trying to
55:48 up to those growing cells, The way this happens, this happens
55:54 puberty. So this is when you're your massive uh growth phase and the
55:59 are bone cells are growing upward. ultimately, what they do is they
56:03 up with these mitotic cells and they them to calcify and die. And
56:08 is I think what this picture kind looks like. So up here,
56:12 this is the region of massive So these are the cells that are
56:16 and what they're doing is they're dividing way so that the most active cells
56:20 nearest up there. The least active are down here as you get further
56:26 further from the active dividing stage, become hypertrophic and they eventually die.
56:31 down here, these are the cells are the bone cells that are moving
56:35 and they're taking over this region of . And so this is eventually going
56:40 get to a point where it's growing than that and catches up with this
56:43 replaces all that. Now, think a little kid and think about the
56:53 of their arm like that, And I think of the size of
56:57 arm is your arm that then or it like this fatter? Right?
57:08 . So you don't just grow along edges, you don't grow just in
57:12 direction, instead, you also grow and this is a oppositional growth,
57:17 ? So, remember we have the , we have the endosteum and those
57:20 osteo progenitor cells and osteoblast and they're down bone. And so as they're
57:25 down bone, the bone is getting and thicker and thicker and thicker and
57:28 it does that the bone gets heavier heavier and heavier and heavier. So
57:31 body is like, I don't want carry that much weight. What I
57:33 do is I wanna break down bone the inside and so on the
57:36 it's basically breaking down bone. So lattice work, that's that spongy bone
57:41 there is also breaking down. And it breaks down, what ends up
57:46 is that the rate at which it down is much slower than the rate
57:49 which it's building. And so what end up with is a bone that
57:52 thicker and thicker and thicker, but make a larger cavity on the
57:56 So your bone gets wider, Because you're growing this direction and as
58:02 grow up, your bones are getting , so they get bigger and
58:06 Appositional is wider. Interstitial is It kind of makes sense, but
58:18 not just doing it on one we have to make that hole that
58:22 cavity larger. All right, pausing for a second stretch. Your brain
58:32 up, look down. Look Look right. Are there questions about
58:36 two things? No one has a of why are girls shorter than guys
58:43 the average? Oh, there is question. Well, I haven't heard
58:48 yet. Yes. What a good . Yeah. Oh, man.
58:59 right. So as you're well men and women or boys and girls
59:05 in a puberty at different times, ? Girls enter puberty at an earlier
59:11 than boys do. Guys are very with this because at summer we go
59:15 in sixth grade or fifth grade, come back, all the girls are
59:18 and all the guys are basically all same. But all the guys know
59:22 girls are walking around like oh girls shapes now, right? We're very
59:26 about that. We don't know why excited about it, but we just
59:29 and then we figured it out about years later. All right. But
59:33 that means is is that the growth , pubertal growth spurt occurs earlier.
59:38 you can imagine. I've got I've got a boy and a
59:40 twin, right? So my daughter my son were roughly the same
59:45 right? And they're growing and then daughter hits her growth spurt.
59:50 notice, did my son stop No, he's just not growing as
59:54 . And so she goes through that spurt earlier, but because of the
60:00 plate closure, she stops growth at certain point and then my son hits
60:06 and then he goes through his growth and then his EHES plate will
60:12 He hasn't stopped yet. It's very frustrating because he's taller than me
60:17 . He's 16. Drives me Dad. How tall are you?
60:24 right. But that's the reason why , when you enter in to
60:28 it's like giving yourself, um, a head start because what's happening is
60:34 it's a race, ladies, you're the race earlier and then you're running
60:38 of fuel, whereas guys are walking they start running and then they get
60:45 run. So they get to go . Second thing, estrogen increases the
60:51 at which the epithelial plate closes. right. So it's, that's just
60:56 of the bargain, right? So get closure of the epithets plate earlier
61:01 guys do because we don't have as estrogen in our bodies. So they
61:06 doing. So you saw that age it said two, the age
61:09 You remember on that said from 10 about 25. So way back in
61:13 day, um I worked for the program and so I was a tutor
61:21 students pass their math classes and their classes. And I remember one time
61:26 four freshmen in an elevator in the . So here I am in my
61:32 ft whatever. And I have a who's six ft 86 ft 76 ft
61:37 and six ft 10 in the elevator me. Right. I'm like in
61:42 tree of, you know, and freshmen and they're not, they haven't
61:46 growing yet. So, you one of them, I think it
61:49 ended up being seven ft one playing Europe. Right. So those growth
61:55 can continue on for a long Man. That was so weird.
62:06 . How are we feeling so Yeah, they can be taller.
62:15 . So that doesn't mean that all who are taller have started earlier or
62:19 later just means the epithelial plate um, hasn't closed. So,
62:25 of the things that you, if take me in a P two ever
62:29 in and we'll, we'll talk about a little bit. Um, but
62:32 speaking, uh, puberty is one those really weird things. Uh,
62:36 , we keep saying, oh, starting earlier and earlier and that's not
62:39 . It's, it's, we've, come to understand when it starts a
62:44 better, but the idea here is are, your height is dependent primarily
62:49 several factors. Genetics is one, ? I mean, if you have
62:53 short parents, what's the probability you're be tall? Not very,
62:57 you're probably gonna be short as but it's nutrition, right?
63:02 so if you eat well and so, uh, we have a
63:05 who has two tall kids, one short kid, the short kid never
63:10 , uh, to, uh, learned to have an adult palate.
63:14 all she does to notice there's she first, but all she does
63:18 eat like pizza and blo cheese sandwiches she doesn't eat food that would be
63:27 to growth. Right. So, your vegetables, kids is, is
63:32 other thing. And then, another thing is being free from disease
63:37 free from, um, stress and like that. That's another factor that
63:42 an important role in growth. I a question there and I've been
63:45 Yeah. Go ahead. It, could, right? And again,
63:54 part of it is is the timing that closure. So if you're going
63:59 a massive growth spurt, which is response to all these other factors,
64:03 gonna go quickly. But the estrogen , if they're, if they're higher
64:08 stunt a person's growth. But so androgens. I mean, one of
64:14 things they tell you is when you're a young, young man is you
64:18 not go and lift weights before your is ready to do. So because
64:22 can stunt your growth when you start in all these hormones or start producing
64:27 androgenic hormones that make you stronger, may keep you squat as well.
64:33 , so the other one. Mhm mhm So this is a really
64:53 question, right? Because I'm, at that point now where I feel
64:56 and I just want to sit around , but that's not a function
65:00 I'm old and I can't do. more a function of, I don't
65:04 do. All right. There's, a difference. Right. So,
65:08 know, one of the things that we, we just presume is
65:11 the older you get, the less you become and, and the other
65:15 is that your metabolism slows down. was a huge study that was released
65:19 four months ago, five months ago they looked at you like hundreds of
65:23 of people data from tons and tons studies. And what they found was
65:26 metabolism doesn't change over the course of life. It actually stays relatively
65:32 What happens is, is we become because, well, I'm just gonna
65:37 the word we're lazy. I if I have the choice of sending
65:40 son out to my yard instead of , guess who's going out, you
65:44 , I'm bigger than him still. so I can make him right.
65:48 , but truthfully it's, it's it's more of an attitude thing.
65:53 , like, you know, I'm gonna pick on grandma for a
65:56 , right? I mean, grandma frail. Grandma is not as strong
65:59 she used to be, you oh, her bones are getting weaker
66:03 the loss of estrogen no longer supports bone growth, you know, so
66:06 the osteo um too many Oscar words my head right now. Um And
66:16 not using the right one I'm thinking , which is something completely different.
66:20 , um, osteoporosis is the word looking for. So it's like they're
66:24 . No, no. What, you do is as you work
66:28 and do the things that you do bones as well as your muscles will
66:34 and be able to do that. don't want to overstress them. In
66:37 words, you don't want to ok. Um, grandma, I
66:39 you to go out and I want to start, um, you
66:43 I don't know, lifting logs, mean, that's, that's unnecessary,
66:47 ? But if she goes and moves thing and then the next day she
66:50 and moves another thing, her body gonna say, oh, this is
66:52 that you regularly do. So it's to strengthen the muscle on the bone
66:55 make that happen. This is why workouts are important, right? Because
67:00 they do is they create a constant of stress, not over stress,
67:04 just a state of stress to strengthen , you know. So what would
67:11 say? Eat your vegetables and also forget to work out, you
67:16 doesn't have to be a lot. don't have to, no one,
67:18 everyone has to be benching 300 you , squatting six, you know,
67:24 do enough, do that kind of the question a little bit.
67:28 Yeah. Yes, ma'am. You're have to speak up a little
67:37 How, how are they flexible that to do. So, the thing
67:40 not talking about when we're talking about skeleton is talking about ligaments,
67:44 So flexibility is in the structure of ligament itself, right? So um
67:53 so collagen and other fibers are there form these ligaments and there are different
67:59 of collagen, there are col collagen have greater flexibility than others. And
68:04 some of us actually have that greater because the collagen in our body builds
68:09 actually unique and different and gives that degree of flexibility. So that's,
68:14 part of it also, it's using those structures as well.
68:19 um you've probably seen people who do are particularly flexible. Why? Because
68:25 day they stretch, right? And basically say these are the movements my
68:29 has to make you look at someone me that looks at yoga and
68:32 is that a food or is that exercise? Because yoga, yoga,
68:37 know, close. Um I I'm not flexible, you know,
68:41 there are days when I'm like get the shower, I'm like, I've
68:43 to just touch my toes because, know, get that hot water on
68:46 back because it's I I I'm just and sore all the time. So
68:51 has to do with, with the portion, not the bone portion of
68:55 skeleton, anything else? Yeah. Just any sort of work, anything
69:09 causes you. So, when we about the skeleton, you, you
69:12 keep in mind that it's really muscles skeleton working together, right? So
69:17 sort of stressor you put on the , right? So when you lay
69:20 the bed, you're putting a stressor your bones, right? You're putting
69:25 in a particular direction. So your has to, to deal with that
69:30 . Now, I'm not saying laying is like, oh please everyone lay
69:33 and that, you know, that's just in one direction,
69:36 If all you do is lay then your body is gonna say I
69:38 don't need to create enough strength so my body doesn't collapse on itself.
69:47 No, no, you're absolutely strengthening think about you pulling yourself through
69:51 through the water, right? Moving water is much more difficult than movement
69:55 air, isn't it? Right? pulling your, you're pulling your entire
70:00 in a, in a medium that resisting your movement. I mean,
70:03 resists our movement as well, but all around us. So when you
70:07 in the water, you're actually fighting it. So you're strengthening your
70:12 right? But you're also strengthen the that are being pulled against because movement
70:17 really your muscles pulling and changing the of your bones. It's kind of
70:22 . Huh? Yeah. Yeah. is one of the reasons why we
70:26 that because it is low impact, ? You're not, you know,
70:30 it. So we get little old again. I'm using little old ladies
70:34 guys aren't gonna do this. but they go down to the y
70:37 all get into the pool and they stay in the pool and they do
70:40 aerobics. Right? Why? Because low impact. It allows them
70:44 to meet that resistance and it makes muscles stronger and their bones stronger.
71:01 . Yeah, because so, so idea here is, you know,
71:06 , we there like my son, was when he was 10, while
71:09 wanted to start lifting weights, I'm , no, no, just,
71:11 be a boy. You go do like if you lift your body into
71:15 tree that's like lifting weights, But the idea here is when you're
71:19 through and your body is trying to itself like in early puberty, then
71:24 you're gonna do is you can have impact on how it's building itself by
71:29 lifting, you know, and doing that the body isn't quite designed to
71:34 yet. Right? I mean, about, think about a, like
71:38 eighth grader or 1/9 grader, I mean, that's when you're really
71:41 to see the male form starting to , right? Boys actually start doing
71:45 guys. Remember everyone's checking out each pecks, like check my picks
71:50 you know, it's like, you can list £30. But
71:53 you get, you start getting that . So that's when you probably wanna
71:56 doing because now your muscles have actually through that, that thing that,
72:01 reconfiguration to be able to do the that men, male bodies are designed
72:06 do. And when we go down rabbit hole hole, it's,
72:11 it's crazy. You guys ready to talking about Dan bones and bones and
72:17 . All right. Um, I know how far we're gonna get.
72:22 Usually when I give this lecture in regular semester, it's like this is
72:25 one class, you know, so an hour and 20 minutes and I
72:28 I usually get done in an So we may not get through all
72:30 bones, but we have the joints and the joints are really easy.
72:34 , um so if we don't complete stuff today, we'll continue on
72:38 And, and again, when when we started this class at the
72:42 of the semester, last week, like, hey, there's two parts
72:45 your body. You have the AEN or the appendicular region, you have
72:50 axial region and the, the skeleton the same thing. We have an
72:54 skeleton which you can see here is in blue. It's basically the ax
72:56 the body. It includes the the vertebral column, the vertebral
73:01 I sound terrible, the ribs. And um that's about it. And
73:06 everything else is appendicular. And so includes the girdles So the girdle includes
73:13 hips and your shoulders as, as as the long bones of the arms
73:17 the phalanges at the end. All . So the way you think about
73:22 axial skeleton plays a role in caring supporting other body parts. So it's
73:27 , whereas the appendicular skeleton is primarily in locomotion. All right. That's
73:34 just a dance that's movement in OK. And I didn't mention there's
73:40 like 200 some odd bones in But what's in saying that one?
73:44 kind of to say, look at end of this, you can pat
73:47 on the back and say, I can memorize 200 things, you
73:49 , it's not, not a Um But really, it's, it's
73:53 kind of give you the sense that , there really isn't as many as
73:56 sounds like. All right. So we do is we start with the
74:01 , the skull, there are 22 here. And so you can think
74:05 the skull as having two parts. have our cranium and we have our
74:09 . All right. So the cranium has about eight bones, the facial
74:13 , there's 14 of them. But , many of these are gonna be
74:16 . So the actual numbers are a less. Now, these are primarily
74:20 bones. All right. And the of joint that they're gonna have is
74:26 a suture. And so we're gonna a, a first type of joint
74:30 , I think someone asked me a about these. Uh yesterday, I
74:33 like, what, what are those ? Well, they're, it's just
74:36 , it's just a type of joint it's referred to as the suture.
74:39 so these are um uh interlocked and it prevents the bones from moving.
74:44 so this is um uh basically your in and of itself is actually a
74:48 , very protective structure. It's for the most part immobile, with
74:53 exception of one bone, which is mandible, that's what sits at your
74:57 of your jaw, right? So gonna start with the cranium and very
75:02 what you'll see is you'll see just views, but the slides may be
75:05 same. So it, it will by pretty quick. Um your
75:10 Uh Well, let me put this , your test, what I'll probably
75:13 is throw you a picture like That's even color coded just to make
75:18 lives easy, right? The they will never do that. I
75:21 , they might, I don't I don't do the lab,
75:23 But your homework won't have stuff like . It will actually having you like
75:27 so you can try to see the . All right. So I'm just
75:30 to give you guys a little bit a leg up on the, on
75:32 lab stuff. But the test for purposes, I'm gonna just keep it
75:36 really simple, just something that's color and you may get a view like
75:41 or a view like that or a like that. All right. So
75:45 regard to the cranium. All we got a couple of bones.
75:48 have the bone in the front. is the frontal bone shocking,
75:53 One in the front frontal. All . Then back here in the
75:57 that's the occipital. All right. are all those are single bones,
76:02 right. And then we have this that's really, really hard to see
76:05 you look from the top. You see it only makes a small portion
76:08 the cranium, but it goes down and makes up the walls of the
76:13 cavity. This is called the ethmoid then the bone that's next to the
76:18 . That kind of looks like a or a butterfly. What do you
76:20 ? Bird, butterfly, bat, , you got bat, right?
76:24 look at it, I see a but I I I see the bat
76:27 ? But this this this bone that kind of has this weird shape
76:31 is called the sphenoid. So we frontal occipital, we have ethmoid and
76:37 on the inside that looks like the , that's the sphenoid. So
76:41 feno, all right. So those the four single bones, all
76:46 And then we have two pairs of . We have the temporal bone,
76:55 right, that sits over here on side of the cranium, right,
76:58 called the temporal because temporal means right. And the first signs of
77:09 his gray hair over here on the of your head, that's where it
77:12 its name. So temporal bone, region and we call it the
77:17 right? Oh I got temples And then on top, we have
77:22 pair of bones here. So two bones and a pair of bones up
77:25 . Those are the parietal, So frontal occipital pair of parietal pair
77:30 temporal, we have the ethmoid and we have the feno that sits on
77:35 inside. You can see it All right. Now, if you
77:38 about the cranium itself, there are parts to it. We have a
77:42 which we refer to as the cranial . You can see the cranial base
77:45 and then we have the round part the top, the helmet portion that
77:49 the vault. So again, you kind of see which parts make up
77:54 . So this total portion right that's a vault. So the idea
77:58 is everything in the in the It is gonna be the frontal,
78:01 parietal and the occipital parts of the , the floor then is gonna be
78:06 parts of the occipital, primarily, primarily uh some frontal, a little
78:12 of Etno, a little bit of . Now, if you look at
78:19 bottom, you know the base, cranial base. What you see is
78:23 there's like three little shelves. All , you can't really see it in
78:27 way. But with get cut away , here's a shelf there, shelf
78:30 , shelf there. Now, what looking at there is we're looking at
78:32 brain and the cerebrum. So that's cerebrum and the cerebellum, this is
78:35 cerebrum, that's cerebellum down there. brain sits on the base, not
78:41 , there's fluid and stuff in the , but basically these shelves cradle and
78:46 the, the brain. And so has this unique shape because of the
78:52 of the brain or vice versa, came first. So the part in
78:57 front right here, that would be anterior FASA, it's made up of
79:02 frontal, the hyoid and the Then we have the middle fossa which
79:07 portions of the feno but primarily temporal . And then the rear is parts
79:14 the temporal bone. But for the part, the posterior fossa is made
79:17 of the occipital bone. That kind makes sense. So we're just think
79:24 the base as holding stuff. And you can kind of see the different
79:27 and you can kind of mis match as you go. All right.
79:31 last thing I want to point out with regard to the base, there's
79:35 big giant gaping hole, name of hole, the big hole frame,
79:42 Magnus, all right, frame and is there to allow for the passage
79:47 the spinal cord. So coming out the bottom of the brain is the
79:52 cord and it extends downwards. So what the big hole is for.
79:59 going to come back to joints like said tomorrow. But I just want
80:02 point out these joint, these are joints. They don't allow, you
80:05 sit there and play with them. brain is not going to move
80:08 your head is not going to move . Those bones are basically cemented together
80:12 these joints. These are called The sutures, the big, the
80:16 sutures are here. We have the . Remember how we said the colonel
80:21 is the statue of Liberty Crown, ? So the coronal suture goes across
80:27 . It separates the frontal from the parietal. OK. So that's that
80:32 and you can see it right here the top. All right, we
80:36 the lambdoid suture. What's a It's a Greek L, right?
80:43 it looks like this. If it's case, if it's upper case,
80:46 looks like that, right? That sense. So, do you see
80:50 we got here? It's not quite lambda. It's a lambdoid, it's
80:55 . So that's where you got its . All right. Remember we cut
80:58 in half. That's the sale So the suture that goes down through
81:02 middle between the two parietal. That's Sagi suture. OK. And then
81:07 got the weird one. I don't why they came up with this
81:11 but it's Squamous. What does Squamous scale? Like it's like flat,
81:15 guess. All right, fine. sits between the prial and the
81:19 So there's the Squamous. OK. those are the sutures you need to
81:26 . And I, someone asked I guess you're not here today about
81:30 bones. There's examples of sesame bones in there. So we don't need
81:35 know them. I'm just pointing them to you. So sutures does make
81:41 . Coronal sagittal lado squamous, you do that in the test. You
81:57 , if you see someone doing that , just, just giggle to yourself
82:03 out of the face, you can why this goes fast because me pointing
82:07 a picture. All right, we two single bones. I'll just point
82:11 out right now. So this is mandible. It is a single
82:15 It's formed by as a single bone then inside your nose, it divides
82:21 nose into two halves. So that be the septum. There's a bone
82:25 that's called the bomer. And you see from a cross section there,
82:29 is in the middle, see that then over on the other side.
82:32 on the, on the outside wall that nasal cathode, that would be
82:35 ethmoid. All right, in terms the paired bones, remember that hard
82:44 up here. That's the nasal All right. I'm just gonna look
82:47 this here. All right. On inside of the orbital cavity right
82:53 All right. That is the lacrimal on either side. Ok. When
82:59 think of lacrimal, you should be tears. That's where the tear duct
83:02 actually located. Tears aren't made They just collect there. You
83:06 when you're sad or happy or we need a good cry. The next
83:14 the Zygomatic bone. Aaron point to cheek. There's your Zygomatic bone.
83:19 right. You got two of All right. Uh Entine, the
83:23 bone is way back in the back your mouth. All right. You
83:28 how, when you're feeling really, horrible and you're sitting there in front
83:31 the toilet and you're like, I , I just got to throw
83:33 So what do you do? You push the trigger? All right,
83:36 like, all right before you get the trigger, right? There's a
83:44 palate, right? So the pines not where the, the front part
83:53 the hard palate. It's the back of the hard palate. OK?
83:57 there's two of them, there's one either side. If you think of
83:59 body being divided in half, it's back there. All right. The
84:04 is the maxilla, which looks like big giant bone. But if you
84:08 carefully right there, you can see is a seam that was two bones
84:11 of grew together and forms this front right here. So it's your upper
84:16 . But it also makes up the part of the hard palate separates the
84:22 cavity from the um uh the the cavity and then on the inside.
84:30 so this is the only place where gonna see a good picture of
84:32 So it's inside here, inside the cavity, you have the inferior nasal
84:38 and so they're kind of little tiny that kind of stick out from the
84:42 and create these turbinates. So what do all these things do?
84:46 , they form the cavities of your senses. That would be your
84:50 your smell, your taste, so , smell, taste turbinates air.
84:54 as air is breathed in, it to move like. So because of
84:58 in uh inferior nasal concha creates an for the air as well as for
85:05 . You can see here with the and the mandible secures your teeth.
85:07 it also serves as these structures serve to anchor all the facial muscles to
85:15 skull. So just know the bones where they're located. So this is
85:24 a different view. So you can much more clearly. Here's the vo
85:27 are the nasal con, you can the palan, the max, it
85:32 you a better sense of where those are located, right? I think
85:36 may have one where you can actually your, like in the book and
85:39 can kinda to turn things over and and look at it. But the
85:42 way to explore this stuff is to go into the lab, pick up
85:46 and talk to it like you're a person and then turn it over and
85:49 with it. Now, there are couple of cavities in the skull.
85:54 have the cranial cavity that's going to the largest uh cavity and that's going
85:57 surround the brain. We have the cavities, that's where your eyeballs
86:01 It has blood vessels, muscles and . There's actually even um for.
86:07 this is the form that's fora that these uh nerves and blood vessels to
86:12 through. Also has a point for lacrimal glands to go into the nasal
86:18 . And in terms of the structures are formed there, you can see
86:21 here is the frontal lobe uh back . This, well, let me
86:25 sure I get this right. There's lacrimal um Here is the Zygomatic and
86:30 the green one right there is, a lacrimal and this is part of
86:33 maxilla. Um And let's see what I missing? Oh Palan, which
86:37 can't see which is gonna be on back side. But that forms that
86:45 , nasal cavity. Again, we do cut through. You can see
86:48 , Bomer, Palantine maxilla on the Etno, we also have inside that
86:54 saw from the inferior view, the uh the inferior nasal concho oral
87:01 this is gonna be uh for Uh We also can breathe through much
87:06 food. So we have the max the uh mandible are the primary
87:11 But also don't forget that we have pas there in the back as
87:15 which is not listed on the When you say your sinuses or you
87:22 a sinus infection. what a sinus sinus by definition is basically a
87:28 What this does is it lightens the . So it's actually a, a
87:32 space inside the bone. That's what little color coded regions are trying to
87:37 you is which bone it's actually located just their name based on where they're
87:42 . So frontal, ethmoids, feno the maxillary sinus, but it lightens
87:49 space. It also allows when you in since it's gonna be open to
87:53 nasal cavity, air goes into that it warms up before it gets pulled
87:58 into the lungs. It also becomes more humid. Um These are gonna
88:03 mucus lined. And so you can like when you have an infection,
88:06 happening is your body's producing all this to kind of wipe out and clear
88:11 the in the infectious agent, which why you get all popped up and
88:15 feel all horrible. It also creates or uh uh to your voice.
88:21 you noticed that we all sounded different we don't sound exactly the same part
88:25 that is because of the resonance that produce when we make sound. It's
88:29 going into those, into that You know, and it causes the
88:33 to vibrate and it's just makes us create that unique sound. So that's
88:38 resonance in our voice. So, many bones have we learned so
88:47 22 out of 210% of the way moving down the neck, we have
88:56 bone. It's called the hyoid It's associated with the larynx. You
89:00 see right here that there is the , it kind of sits on its
89:03 . It's not attached to any other in the body. It's actually held
89:06 place by a series of ligaments and , two features to this. So
89:12 you swallow, it moves up and , but two features is it has
89:15 , these projections, one is called lesser horn and it has um ligaments
89:21 which or muscles to which they're And then this is the greater
89:25 So here's the ligament you don't need know the styloid stylohyoid, stylohyoid.
89:32 just notice whenever you see these they're just telling you what they're attached
89:36 . That's, it's really how the works. So if you ever get
89:40 of confusing attached to the stylus attach to the high bone.
89:46 but don't worry about the name right and then there's bones, I
89:49 muscles to which these are attached, ? It helps you in terms of
89:54 . That's the whole purpose of Whenever you have a bone, a
89:58 is there a muscle to pull, on. And that's what it's doing
90:01 . Swallowing and speech. How many , how you burned every night?
90:10 . Ok. I'm gonna keep asking . All right. Vertebrate. We
90:13 a whole bunch of them. All . So there are five divisions.
90:17 you look at them, they all in kind of a different way.
90:20 you can see here there's different right? So, in terms of
90:25 different groups, we have seven cervical , we have 12 thoracic vertebrae,
90:30 lumbar, five Sarel and ultimately four . All right. So you can
90:35 up there seven. Now, here's weird thing. Do not write this
90:38 . Do not memorize this. I'm showing you how screwed up the world
90:42 . Truthfully, the majority of people the world have seven cervical vertebrae,
90:46 some of us have eight. About we see. We have 50 people
90:50 this class. Six of you likely eight cervical vertebrae, about 30% of
90:57 population. That weird. So Actually. That's not right. It
91:06 be six, 30% of 50 Yeah. See everyone's unique. It's
91:18 . All right. How do I how many bones are each in these
91:23 ? Do I sit there and What do you do. And
91:28 oh, you're so smart. I it. Everyone listen to her.
91:33 do normal people eat breakfast? Notice had to use the word normal because
91:36 guys probably didn't eat breakfast this What time do normal people eat
91:41 Seven AM. When do normal people lunch, noon when the normal people
91:46 dinner? Five and then they have and then you wake up in the
91:53 of the night. And what do have a snack at four? See
91:57 it works. You'll never forget I'm glad you remember that.
92:01 that's how I learned it. So the same thing for you.
92:04 what I wanna point out is when were born, you were shaped like
92:06 letter C, right? Your spine shaped like the letter C but you
92:11 longer are shaped like the letter Instead what you have is you have
92:14 series of curvatures, concave convex, , convex. And then this one's
92:19 of weird. All right, that's your remnant tail. It could
92:24 longer. It shouldn't be. Um you know, when you say I
92:29 my tailbone, that's what you're breaking there. The little cox. All
92:35 , Sarel and Cox, these are . So that's basically it's gonna appear
92:40 one bone. These are gonna appear one bone right now. Why does
92:45 spine curve because it makes you more a spring? Um Anyone here ever
92:50 ? Uh nature shows ever? Do ever watch this nature show with a
92:55 ? Watch Cheetah Chase down one of little tiny fast gazelle. And what
92:59 do, it stretches out and stretches out and squishes when it's
93:03 It's like, well, that's what do when you walk. Right.
93:08 basically are a spring and what this is the force of bearing your weight
93:13 on this because you do weigh a for your spine. What it does
93:17 it puts the weight in different And so the weight doesn't go straight
93:23 , it's being dispersed in different So you don't bear as much weight
93:27 you normally would. And that's why acts kind of like a spring.
93:31 right, gives you a lot of . All right. So we know
93:36 are 7 12, that's 19 plus , 29 plus four. That's
93:42 So 23 plus 23 it's 46 bones we've talked about. Let's take a
93:46 at the different vertebrae. All So the different vertebrae all have a
93:52 shape to them. All right, general shape is simply this, we
93:58 a body, right? So this the thing on which all the vertebrae
94:02 built. So you can see your , body, body body, they're
94:04 stacked on top of each other. this is putting bone on top of
94:08 and in between each of these we're gonna see an in intervertebral disc
94:12 disperse some of that weight. All , but not only do we have
94:17 body, we're gonna have these projections ultimately form a for a what is
94:24 for a, it's a hole and spinal cord is going to travel through
94:31 hole. So notice the spinal cord not the vertebrae, the spinal cord
94:35 next to the vertebrae. It's protected the vertebrae. So the purpose of
94:39 bone is to protect the spinal And because this is a hole between
94:44 the bones, you can see it this tunnel, it's flexible and so
94:48 spinal cord is can move around in flexible space. This frame is formed
94:55 what is called the vertebral arch. a composite structure from the different extensions
95:02 you see working around. All we have peta calls the pentacles are
95:07 portion and this right here are the . So there's lamin on number
95:11 lamina, number two, that is forming the arch. OK?
95:17 the arch which creates the, which next to the body, we still
95:21 all these weird things that are going in different directions. Where are the
95:24 things? These are called processes? right, if you feel on your
95:29 , do you feel the bump, bump on your spine? You feel
95:33 that is the spinal process? That's the part that's sticking outward.
95:39 right, then we have two processes extend this direction, all right,
95:47 , so they poke outward and then you can't see real well is below
95:54 transverse process. And above on the side of the transverse process, we
95:57 two more processes is to call the process. When you see the word
96:02 , that is for an articulation, is the fancy anatomy word for saying
96:06 joint. Ok. So the superior articular process articulates. So there's a
96:18 , one articulates with the inferior articular of the vertebrae above it. So
96:26 have a superior and an inferior. on the other side, you have
96:29 superior which is articulating with an And this is how the different vertebrae
96:34 interacting with each other. That kind makes sense. So that's how they're
96:39 like so and they're interlocked. And I mentioned in between each of the
96:47 of the vertebrae, you have these intervertebral discs. Your book is the
96:50 book I've ever seen that actually shows in perfect condition. This is what
96:53 supposed to look like. You can on the outer portion, we have
96:57 really, really thick fibrous region, called the annuus fibrosis. And inside
97:01 have the squishy reach region that is flexible, it's called the nucleus
97:06 If you've ever had the shoe you know, the gel inserts,
97:10 can think of it like that on outside, you can step and it
97:13 the pressure that's outward So the forces are being applied downward are being distributed
97:20 from that pressure. So, distribute some of the force. But
97:26 you tear that annuus fibrosis, what end up with is that nucleus pulsus
97:33 outward. And in this particular this is a herniated disc. In
97:38 particular case, it's impinging upon the cord and causing a great deal of
97:45 and distress in this particular individual, ? So this herniated disc is a
97:49 of the annuus pulsus, allowing the or annuus fibrosis to allow the nucleus
97:54 to to escape outward. That's what hernia disc is, right. But
98:00 discs basically uh a pad of cartilage distributes force away from the vertebrae.
98:08 , I'm showing you this not to , I'm showing you this to show
98:11 that it doesn't matter where you are vertebrae have different shape, but they
98:15 contain that same sort of structure. for example, you can see here
98:20 processes, you can see the transverse , there's a spinous process. This
98:24 be what the cervical region looks like here. This is kind of what
98:28 already look like. This is But when you get down the lumbar
98:31 notice here that the transverse processes aren't broad, but the spinous process is
98:36 broad, right? Or it's And you can see here differently shaped
98:41 articular processes. Do they all have body? Yeah. Do they all
98:47 an arch, you know, do all have a yes. Do they
98:51 have the spine or the different Yes. So, yes,
98:55 Yes. To all that differently different shapes mean different function. This
99:03 where I used to make you guys up but I know we're running out
99:05 time. See, look at the of movements I can make up
99:11 right? Trying to just stay But look what I can do down
99:15 in my hips, right? I different movement. Look at this,
99:22 can rotate but I can't rotate quite well up there. But my
99:28 I can rotate really well. In , I even have more range of
99:33 up in my neck. It's all of the different shapes. The acid
99:40 are unique in that they also have with the transverse process. A facet
99:46 articulation with the rib. All the rib is called the costal
99:52 And so that little uh articulation is the costal facet, all right.
100:00 place where the rib touches, that's it means. All right. So
100:04 will see this in just a But the thoracic um vertebra, how
100:11 thoracic vertebra were there? 7, , 12, how many pairs of
100:17 do you think you got? See it makes it simple because you
100:24 that the ribs are associated with the vertebrae, not any of the
100:30 Sam and the cox. These are weird ones, as I said,
100:33 fused. So you can see here the sam. Um the sarum itself
100:37 five fuse vertebrae, right? You um an articular process that's superior,
100:44 there's no inferior ones because they've been together with the superior one below
100:48 So this is a structure that you up, it looks like one
100:51 Um You have a series of mina you can see here for a and
100:56 and for and for those four Amena blood vessels and nerves to pass
101:00 So they can go on down to legs and finally down here, that's
101:04 cox. So that's the four cocci are fused together. So remember what
101:10 said, you're gonna be fusing bones a long time. Here's an
101:13 One, this fuses around age So right now, a lot of
101:17 is still cartilage for you guys, it's getting close. All right,
101:23 here ever bruised or broken the it's a whole world of suck just
101:28 you know just terrible. One of worst things ever because this ligament is
101:34 to it. Many bones are attached not bones, many muscles are associated
101:38 the ligament. So every movement is pain. If you bruise or,
101:42 break that bone don't do that, fall on your butt. Yeah.
101:49 she went. Yeah. The worst . Uh All right, we're getting
101:55 , I'm just gonna finish up with thoracic cage when we done with the
101:59 skeleton. Ok. So the thoracic is the fancy word for saying the
102:03 and the bones that are associated with ribs. Um I wanna start here
102:07 the stum. All right. So is your sternum. It has three
102:11 to it. Um The purpose of sternum. Notice where it sits,
102:14 sits in the middle of the cavity here. Its job is to protect
102:17 heart, right? Keep things from . It doesn't keep it from being
102:23 though, just trying to keep you . All right, three parts and
102:31 what I have here is I have tie because it kind of looks like
102:34 tie. This portion right here is the manubrium. The manubrium is the
102:39 that articulates with the clavicle as well the rib. It's only showing you
102:44 here that are that articulate again, means a bone touching another bone.
102:49 will point out here that it's not bone to bone. What we have
102:52 we have a series of cartilage in . So um you can see down
102:56 , we're gonna get to some really long cartilage. This region right
102:59 is called the body. It's also called the gladius. All right.
103:04 here's another fun one. What's the ladies, do you guys know the
103:08 really, really long flower with a of flower things? It's about this
103:13 , you know, what it's starts with a G L clad.
103:20 you ever heard that? You Gladiolas are no. Ok. Um
103:24 , I'm asking the guys now, is the, uh the, uh
103:28 guy that fights in the arena? in Rome, ancient Rome gladiator right
103:35 ? Romans are really simple people. name things for what they do.
103:38 are called gladiators because they run around a sword called a Gladius. Gladiola
103:46 because it looks like a sword gladiator it carries a sword. What does
103:51 look like? Looks like a Really? That, that sounds,
103:57 silly. We name things. All . Very bottom part. This is
104:00 zip void process. Remember I said got things that are lasting forever.
104:04 is the one that ossifies around age . It's the little bottom portion of
104:09 tie. All right. This is point for the abdominal muscles. Uh
104:13 ever been sucker punch in the uh process? Yeah, it's a lot
104:17 fun, isn't, it doesn't have be someone throw a ball at you
104:23 . So you lose, you lose the wind. All right.
104:27 Looking at the ribs real quick. Remember they're attached to the thoracic
104:32 So like I said, there is here, you can see the 12th
104:35 down there. The 11th one comes . Notice here we have special
104:39 We, the first seven are called true ribs. They're the real
104:44 The other ones are the fake Well, no. Right. Why
104:47 call them true ribs because they're directly to the sternum. See how this
104:53 goes directly and is attached to it . And then once you get below
104:58 seven, the rest are the false . Number eight, attaches to number
105:02 , number nine, attaches to number . Number 10, attaches to number
105:06 . Ok. So they're not attached to the sternum. And then the
105:11 2, 11 and 12 are false , but they're even weirder false ribs
105:15 they don't have any cartilage. They . These are the ones when you
105:18 about uh athletes breaking a rib. know, this is usually the one
105:23 they're talking about these floating ribs because not held in place by anything,
105:28 ? This type of cartilage in between called costal cartilage. Basically the rib
105:34 . And I think that's all we here for the ribs. Oh,
105:38 structure. Oh, my goodness. just keeps going. All right.
105:43 are looking at a rib from the of the uh vertebrae. All
105:49 So what we're looking at is this close to the vertebrae, this is
105:52 here near the sternum. All So we're looking through the body here
105:56 to kind of help you see what looking at the long portion of the
106:00 that comes up and around. So gonna come like this, that is
106:04 to as the shaft, the head the portion of the rib that's attached
106:09 the body of the vertebrae. All . And what we're gonna do is
106:12 gonna go from the head down to neck, right? So here's your
106:16 , head to the neck. And the next portion here as it turns
106:21 called the angle. So the angle what allows you to curve out to
106:25 the shaft. So head neck angle and then the point where the angle
106:31 is the point where we're attached to transverse process, right? So that's
106:36 costal facet. This point here on rib is called the tubercle. So
106:44 neck, sorry head, neck, angle and then coming around, that's
106:49 shaft. Ok. Now, this a flat bone and it's a flat
106:54 . Not even though it has this to it, it's flat because if
106:58 take a slice through it and you at it, you're gonna see that
107:00 shaped this way, it's not And then here we can stop because
107:07 moving on to the axial skeleton. my goodness, it just kept going
107:11 forever, didn't it? All So when we come back, we
107:18 start with the axial skeleton, it really fast when we go through the
107:23 go through the aar skeleton because let's , are your arms exactly the
107:29 Yeah. Are your legs exactly the . Yeah. So they're mirrors of
107:32 other. All right. But we went through roughly half the bones of
107:37 body already. You know. So there's 12 ribs but there's actually two
107:43 . So you 48 ribs, so not 48 24 ribs. You guys
107:48 a great day. I will Is tomorrow Thursday? Are we already
107:52 , wow, he goes quick. it be nice if schools like this
107:56 the time? No, you guys a great day. Enjoy your
108:01 Kick butt, learn stuff. If have questions, I'll be
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