Full transcript
0:02hello everyone and welcome to another
0:04session today
0:06for& um couple of housekeeping things
0:09remember that when we see each other
0:10physically again on September 14th we
0:13will have a quiz um after you take your
0:16quiz and we go over our quiz we'll have
0:18a little bit of a break and then we will
0:20go and take our lab practical lab
0:22practical covers all of unit one and uh
0:25that would include all the histology and
0:27all those directional terms you will
0:29also have doe your worksheet so your lab
0:32worksheet will also be due remember I
0:34don't grade it for correctness I grade
0:36it for completion but I know that some
0:37of you all kind of had a few questions
0:39about some of the structur that we were
0:42looking at um uh specifically
0:46for uh like let part four where it has a
0:49directional terminology a couple of
0:51hints when we're talking about a cat
0:54we're want to use the terms ventral and
0:56dorsal um another hint I want to give
0:59you is that there can be more than one
1:01correct answer for those um terms so I
1:05think one of them was about the navl and
1:07the hipbone the uh the naval in
1:10comparison to relation to the hip bone
1:12or the hipbone relation to the naval is
1:15you could say lateral or you can say
1:17inferior so there can be more than one
1:19answer for those questions on especially
1:21on part number four those lettered
1:23sections there can be more than one
1:25correct answer and also remember when
1:27we're talking about a cat or an animal
1:29we use the terms ventral and dorsal we
1:31kind of reserve the terms anterior and
1:33posterior more for human species so
1:36those are all of our little
1:37announcements um your quiz remember is
1:40going to cover the lecture that we had
1:43on
1:45831 I believe it was I'm looking at my
1:49calendar here um the lecture that we had
1:53on uh August
1:5529th August
1:5727 and to well wait a minute I think I
2:00went back too far the lecture that we're
2:04having today which is September
2:099th the lecture that we had last
2:14Wednesday which was September 2nd and
2:17then the lecture that we had on August
2:1931st so that's what's gonna your quiz is
2:22going to cover the August 31st lecture
2:25the September 2nd and today's lecture
2:27the September 9th will be with's on your
2:30was all right so before we get finish up
2:33chapter five here questions comments or
2:35concerns about
2:39anything and I have also received all a
2:42lot of your emails about um our exam and
2:46the dates that you can't do and I have
2:48several students that are going to take
2:50it on Wednesday at 5 o'clock or in that
2:54time frame so um if you've emailed me
2:57about an examination and I have not
2:58emailed you back um please be sure to
3:01email me again because it means I
3:03somehow I didn't get it or somehow see
3:05me during my office hours so that we can
3:07make sure that we get a Time arranged
3:08for
3:10you okie dokie so where we last stopped
3:13on this last
3:15Wednesday um was that we were talking
3:18about how illnesses can manifest
3:20themselves as variations of skin color
3:22and one of the first ones we talked
3:24about was jaundice um for babies newborn
3:26babies that have a little touch of
3:28jaundice on there were're not super
3:29super concerned unless they're just
3:31really really premature they have a lot
3:32of other um health conditions but a lot
3:36of babies I think uh say two out of my
3:40four children were born with just a
3:41little touch of jaice and a lot of times
3:43they'll put them under the build of
3:45ribon Lights in the nursery or they can
3:47even send you home on time with a billy
3:49blanket um which is just a little UV
3:51light that you wrap around their little
3:53abdomen and for my oldest daughter they
3:55the recommendation the prescription was
3:57to just sit her in the sunlight for a
3:59little while every day um and that helps
4:01to break down that bile that causes the
4:04yellowing of the skin and of the whites
4:06of the eyes now when you get to be an
4:07adult when you're no longer a newborn
4:09it's not because your liver and your
4:11body parts are just newly functioning um
4:14it's usually a condition where your have
4:16jobs is because there's some sort of
4:18liver failure so your liver is not
4:19functioning because it's not super new
4:22it's functioning because it's disease
4:24for some reason or another um we talked
4:26about Addison's disease where it's what
4:28we call hyperpigment M mation so it
4:30causes the skin to have a darker
4:32coloration to it and this is disease of
4:34the pituitary gland we'll talk about
4:35Addison's disease again towards the end
4:37of semester in the endocrine system um
4:40and we talked about how JFK is probably
4:42one of the most famous people um that
4:45you may recognize as an individual who
4:47had Addison's disease and then Vitiligo
4:50which is hypopigmentation it's on the
4:52other end of the spectrum from Addison's
4:54disease is a loss of melanoid so those
4:56cells that are responsible for giving
4:58coloration to the skin um they are no
5:01longer there so as a result you see this
5:03hypopigmentation in various areas um
5:06around the skin um the most notable
5:08person you may recognize that had the
5:11Delo with Michael
5:14Jackson so moving on to other parts of
5:19the integ remember the inment is
5:21composed of two portions we have the
5:23cutaneous membrane and the accessory
5:25structures the cutaneous membrane
5:27consists of the epidermis which is the
5:29layer of cells on top there are five
5:31layers in thick skin and only four
5:33layers in thin skin thick skin we find
5:36where again where do we find thick
5:51skin Palms of the hands and Souls of the
5:53feet awesome Rachel so yes that's where
5:55we find thick skin and then thin skin
5:58well that's just everywhere else I
6:01forgot to turn that thing on all right
6:04and we also talked about how the
6:05cutaneous membrane which is one part of
6:07the anagement is separated into two
6:10portions we have the uh epidermis and
6:12the dermis the dermis so we talked about
6:15the epidermis and how it's got those
6:17five layers the straum deriva on up to
6:19the stum cornea um the dermis now we're
6:22going to talk about has two layers to it
6:25it's got what we have circled in red
6:27here what we call the papillary layer
6:29that is the most apical portion of this
6:31or the top layer of the dermis and then
6:33we have the bottom layer called the
6:34reticular layer in that apic or
6:37papillary layer the top part of it the
6:40type of tissue that you mainly find is a
6:41realer tissue so if you remember from
6:43our histology discussion a realer tissue
6:46is kind of that Jackson poic open
6:48framework abstract art looking type of
6:50tissue um we have some very small
6:52capillaries that are in that regions so
6:54there we have some of those capillaries
6:56there and the nutrients would be a
6:59diffusion
7:00and osmosis go to the different layers
7:02of the epidermis because remember
7:04epithelial cells are avascular which
7:06means they don't have a a direct blood
7:09supply um you also have um some
7:13lymphatics and some sensory neurons so
7:15there we have that sensory neuron the
7:17tactile car pusle um right here at the
7:20top of the dermal layer in your
7:23reticular layer down here
7:25below um you have more of a dense
7:28irregular connective tissue so it's not
7:30a realer connective tissue remember with
7:32dense regular dense irregular connective
7:35tissue has a bit more of an open
7:37framework it was kind of the moderate on
7:39that spectrum of tissues itself um lots
7:42of larger blood vessels would be found
7:44in this area more lymphatic vessels not
7:47shown in this picture but lymphatic
7:49vessels would be running along in this
7:51area um nerve fibers not just the the
7:54nerve the centy neuron itself but the
7:56actual fibers would be found down here
7:59um and then you also may have some
8:01collagen and elastic fibers in the
8:03dermat itself and the overstretching of
8:06those collagen fibers in the dermal lay
8:08is what leads to stretch marks and we'll
8:10talk about those a bit more in a
8:13sec so some things about the dermis we
8:16are issues we can have with is what we
8:18call dermatitis which is an inflammation
8:20of the top layer of the dermis the
8:21papillary layer and things that can
8:23cause dermatitis are an infection
8:25radiation mechanical irritation so
8:28you're constantly having some friction
8:30with uh something constantly rubbing
8:32against that area can cause this
8:33inflammation of that top layer um
8:36chemicals poison iy poison oak those are
8:39all considered what we call contact
8:41dermatitis because you've come into
8:42contact with these different poisons um
8:45some of the features of this
8:47inflammation or of or dermatitis is
8:50itchiness and pain and there's usually
8:52some swelling that accompanies it as
8:55well along with your dermis in your
8:58dermal layer you're able to um make what
9:02we call Vitamin D3 or cocal forol Co
9:06vitamin D3 is kind of a misnomer usually
9:09when we give something the name of a
9:10vitamin we say that it's something that
9:12you can't you have to get outside of
9:15your body so you have the vitamin has to
9:17come from some sort of external Source
9:20whereas with cocalero vitamin D3 you
9:22don't have to get vitamin D3 outside of
9:25your body because your body makes
9:27vitamin D3 so we it's kind of a misnomer
9:31now we do fortify a lot of our um foods
9:35with vitamin D3 milk and orange juice
9:38would be great examples of that that
9:39there they can be fortified with vitamin
9:41D3 but in the presence of sunlight your
9:45body will actually manufacture this this
9:48is an excellent question for a short
9:50answer question because this is actually
9:52giving a process of how does your body
9:56manufacture vitamin D3 so in the
9:59presence of sunite your epidermal cells
10:02are going to make this compound called
10:04cocal
10:05cerol that cocalero is then going to um
10:10make its way to your liver and your
10:11kidneys via the bloodstream so the
10:14cocalero that's manufactured in the
10:17presence of sunlight um it's going to go
10:19diffuse into those capillaries or the
10:21capillary layer of your dermis and then
10:23further down into the larger blood
10:24vessels of your dermal layer and then on
10:26into your bloodstream and so forth so it
10:28kind of Mak makes its way to your livers
10:31and your kidneys where vitamin D3 is
10:33converted into calcal the importance of
10:37vitamin D3 is so that it can Aid in
10:40calcium and phosphorus absorption we
10:42need that calcium and phosphorus
10:44absorption in order for your bones to
10:47maintain their heartiness so this
10:49concept of vitamin D3 we will come back
10:51again when we go into our next chapter
10:53of the skeletal system but in order for
10:56um the calcium and the phosphorus to be
10:58properly absorbed and become the calcium
11:00phosphate or Hydro hydroxy aetate that
11:03um is responsible for the hardiness of
11:05the bone it gives them their you know
11:07makes them nice and hard um we require
11:10vitamin D3 for that if you have
11:13insufficient vitamin D3 that's either
11:15made or ingested by the body it will
11:18cause those bones to sort of bow out and
11:20be much weaker than they normally should
11:22be and that bowing out of the bones is
11:25what we call
11:26brickets so understanding this process
11:29um is a great short answer question and
11:31I could ask something along the lines of
11:33what is the importance of vitamin D3
11:36explain how this process um takes place
11:40with sunlight in your epidermal
11:43cells so this I said before insufficient
11:46vitamin D3 can cause rickets or as my
11:49grandmother would call it the rickets
11:51and she always told us and we my
11:53grandmother is from Mobile Alabama which
11:55is as far south as you can get in the
11:57state of Alabama without being in the
11:58Gulf of Mexico so she's from the deep
12:00deep south and she would always tell us
12:03and and keep in mind in the summer it's
12:05like really really really hot and we're
12:08from up North we're from Northern
12:10Illinois where we only really get like
12:13an 80 degree day was like a scorcher for
12:16us where we were from so when we went to
12:18go visit my grandmother in Alabama she
12:20would make us go outside and play and
12:23she would tell us you better go outside
12:24and play and play outside or you're
12:25going to get the rickets well she was
12:28partially Cor in that we really don't
12:30see children at least not in the United
12:32States and more um industrialized
12:34countries that have the rickets anymore
12:36because our so many of our foods are
12:38fortified with vitamin D3 and now that
12:41we I look back and I understand this she
12:43was right she had a point where she grew
12:46up in Maran Alabama um they got their
12:49milk from Bessie the cow and Bessie the
12:51cow's milk was not fortified with
12:53vitamin D3 they didn't have that
12:55fortification in it so just drinking
12:58milk alone with not going to be enough
13:00to give you the vitamin D3 that you
13:01needed because it wasn't in the milk so
13:04if you didn't go outside and play if you
13:05were kind of sickly and you just didn't
13:07go out to play very much then you saw
13:10these children that weren't getting
13:11adequate sunlight had this bowing of the
13:13legs which was called the Ricket so she
13:15always said you know if you don't go
13:16outside and play you're going to get the
13:17rickets and we had no idea really what
13:20the rickets was but it sounded like
13:22something you didn't want to get so we
13:23played
13:25outside uh dermal skin damage uh a
13:29little bit we talked about already
13:30stretch marks typically happens from
13:32excessive weight gain and weight loss
13:34and that's just the pulling of those
13:36collagen fibers in the dermal layer the
13:38reticular portion of the dermal layer
13:40that get pulled and pulled and pulled
13:42and then they just don't snap back like
13:44they used to um weight gain does the
13:47same thing and you lose that weight
13:49pregnancy is basically massive weight
13:52gain massive weight loss in a relatively
13:54short amount of time whether or not you
13:56get stretch marks from weight gain or
13:58weight loss or pregnanc is completely
14:00genetic some people just don't get
14:02stretch marks it's just the way that
14:05cookie crumbles some people do get them
14:07so it's all completely genetic and what
14:09I have found is that no cream
14:12slab anything that you put on it if
14:16you're just genetically predetermined to
14:17get stretch marks it's going to make
14:19them go away they're going to kind of
14:21always be your
14:23personal reminders of where your body's
14:25been um sagging and wrinkles can be
14:29caused by dehydration so make sure you
14:31stay well hydrated at all times um age
14:35obviously the collagen um underneath
14:38your skin starts to lose some of its
14:40elasticity so as you begin to age um you
14:43may start to experience some wrinkles I
14:46personally reject that notion so that's
14:48not going to happen for me um hormonal
14:50changes in your body so accompanying age
14:54um you definitely have some hormonal
14:55changes that can also affect the
14:57elasticity in the dermis underneath your
14:59skin and your collagen fibers and your
15:00elastic fibers and the abundance of
15:02those fibers and then ultraviolet light
15:05so UV exposure um another great reason
15:09other than the prevention of malignant
15:11melanoma um another great reason to wear
15:13your sun block when you're going outside
15:15a lot of makeup and Foundation um for
15:18women or people that wear makeup has a
15:20UV or SPF protection in it um to prevent
15:26uh pre uh uh
15:30wrinkles that come too early premature
15:32wrinkles and so definitely wear your
15:34sunblock and if you wear a foundation or
15:36even just um moisturizers a lot of
15:38moisturizers already have SPF in them
15:41and no matter how Darkly complexed you
15:43are it's never a bad idea to put on some
15:45sort of light UV protection um just to
15:48preserve your skin and to save it from
15:50damage and also from
15:53melanomas also within your dermis you
15:56have what we call lines of cleavage and
15:58these are pure parallel lines that will
16:00remain shut when the wound heals if you
16:03make a cut that is parallel to your line
16:06of cleavage anywhere on here then when
16:08it heals it's going to be nice and and
16:10secure in there why that's important to
16:13you as a practitioner is that you want
16:15to kind of have an idea of how the lines
16:17of cleavage are running so that when you
16:19perform surgery on a patient that when
16:22the wound heals it will have minimal
16:24Scar Tissue um and it'll be less likely
16:27to leave scarring or to pull apart if
16:30you make a cut at a right angle across
16:33um a line of cleavage it has a tendency
16:36to produce more scar tissue and it it
16:38may have a tendency to pull
16:41apart so now below the dermis we have
16:44the hypodermic layer um it's underneath
16:46the ingent this there is more um elastic
16:49tissue here and a realer tissue and fat
16:52so more loose connective tissues you'd
16:54find in this area um underneath the
16:58dermal layer so right down here um you
17:01also have what we call the cutaneous
17:03plexus which is just a network of blood
17:05vessels in that area um you don't have
17:08any vital organs in your hypodermic
17:10layer um but this is also the side of
17:13what we call subcutaneous injections
17:15that require hypodermic
17:18needles so one of the few accessory
17:21structures that we're going to talk
17:22about hair and nails remember in your
17:24textbook it has this whole Litany of a
17:27of item and things you should know about
17:30the hair and the nails and I'm not going
17:31into that detail so only what we discuss
17:34here on our collaborate sessions is what
17:36I want you to know about the hair and
17:38the nails and the glands for those
17:39accessory structures so those are the
17:41three accessory structures that we're
17:42going to hit on the job of the hair is
17:45for protection and insulation another
17:48job of the hair is that it guards
17:50openings against particles and insects
17:52even in your ear you have little hairs
17:55that stick out in there the job of those
17:57hairs is that for any little buggies or
17:59any particles that are trying to get
18:01into your ears they get stuck in those
18:03hairs as long as well with your ear wax
18:07um so it helps to prevent things from
18:09getting inside your body if you look in
18:11your nostril you've got hairs there so
18:13that opening that it's protecting um
18:15it's keeping um insects and particles
18:18from getting into um your nose your
18:21hairs are very sensitive to very light
18:23touch and we talked about this in their
18:25our first part of these notes that if a
18:26mosquito lands on you and it lands on
18:29one of your hairs sometimes you're able
18:30to swat that thing away before it gets a
18:32chance to stick out um it's little
18:34probiscus and take some blood from you
18:36because you can still that um mosquito
18:38landing on you and that you can uh
18:42perceive that very light touch and
18:44you've probably notice if even just one
18:46hair in your head moves you can feel
18:49that so some aspects of the hair in the
18:51hair shaft um we have sebaceous glands
18:54the job with sebacean gland is to
18:56lubricate the hair and then it ALS o
18:59contains seum um spacious gland so seum
19:02is the liquid that helps to control
19:04bacteria so it has an antimicrobial
19:07aspect to it we also have the erector
19:09muscle which is a smooth muscle all of
19:12the smooth muscles in your body they are
19:15under your involuntary control which
19:17means that you cannot make them contract
19:19just by thinking about them it's some
19:20it's a different part of your brain that
19:22controls a contraction and relaxation of
19:24any of these smooth muscles other places
19:26You' find smooth muscles in your organs
19:29such as your esophagus and your stomach
19:30those are places a smooth muscle your
19:32uterus Etc so for this particular smooth
19:35muscle it's what it causes your hairs to
19:39stand up on in or what produces
19:41Goosebumps so when this muscle contracts
19:44it will produce Goosebumps and it's
19:46called the erector pil ey and then we
19:48have the hair shaft itself the hair
19:50shaft is not directly attached to the
19:53integrant however at the hair root it is
19:56attached to the ingate so this is well
19:58below the surface of the hair we're down
20:00here um past the epidermis and into the
20:04dermal layer where we find the hair
20:09root the types of glands that we find in
20:12the skin well one we've already talked
20:13about that's a basus gland um or your
20:16oil glands not only do you have a
20:18sebaceous gland that's attached to your
20:21hair but you also have oil glands all
20:23over your body and some of us just make
20:25more oil than others the type of gland
20:28this is is the type of secretion we have
20:30for the sebaceous glands and this is an
20:32also a very important concept to
20:34remember remember back in chapter 4 we
20:37talked about the various different modes
20:39of secretion between holocrine merocrine
20:41and appline secretion where here are
20:44some examples of glands that produce
20:46this sorts of secretions or how we get
20:48this stuff out of the gland itself so
20:52for holocrine secretion remember the
20:54entire cell ruptures in order to get the
20:57secreton or thing out of the cell oil
21:00glands are an EXA excellent example of
21:03that so we they will secrete seum by
21:05causing the whole cell to rupture for
21:08your sweat glands you have two different
21:10types apocrine and maracine secretion
21:13glands the aocr glands those are what we
21:16call our stinky glands so for the ocine
21:18secre secretion that would require the
21:21top of the um the cell the apocrine
21:25portion of the the apical portion of the
21:27cell to come off and we talked about how
21:30memory glands sort of work that way so
21:33the top of it comes off and that's how
21:35the secreton gets out so we find aicr
21:37glands in your armpits around your
21:39nipples and your groin kind of your
21:42stinky places places that have a
21:44tendency to get stinky interestingly
21:46enough it's your stinky places that
21:48people are attracted to or not attracted
21:52to so kind of your pheromones um are in
21:54these different come from these
21:55different glands Marine Marine glands um
21:59are more widly dis distributed these are
22:02the ones that are responsible for that
22:03sensible perspiration sweating you know
22:06cutaneous evaporation um whereas we we
22:10talked about how we had insensible
22:11perspiration where your body just loses
22:13water off to the environment but you're
22:15not really sweating it doesn't make
22:17sense that you're losing it but just
22:18because of the laws of diffusion we have
22:20water leol so the maracine glands
22:22responsible for what we call Sensible
22:24perspiration and that cools the skin or
22:27what your book and what you've probably
22:29heard of it being called as well as um a
22:32cutaneous evaporation so definitely
22:34water and some salt you ever lick
22:37something sweaty or yourself when you're
22:38sweaty um it tastes salty so um those
22:43are electrolytes so sodium chloride
22:45potassium things that you lose off and
22:47then another job of these glands is that
22:49they help to flush microorganisms off of
22:52the skin and any harmful chemicals so it
22:54helps to kind of flush the skin um of
22:57anything that could possibly go systemic
23:00and get inside it kind of has an
23:03antimicrobial um role or function to
23:07it so when we need to repair the integ
23:11if there's been an injury to it um first
23:14thing that happens is that bleeding is
23:16going to occur when that bleeding occurs
23:19that's going to trigger these mass cells
23:21and mass cells are denoted by this
23:25little guy here um it's going to trigger
23:27these mass cells to under go
23:28inflammation and as a result of that
23:30inflammation they're going to release
23:32chemicals that will cause other cells to
23:35come to the area in order to try to heal
23:37it so you have a scab that forms on top
23:40eventually and then you have gered cells
23:44that were called to this area by the
23:46mass cells through that inflammation or
23:47inflammatory response that are kind of
23:50rebuilding the dermal layer and
23:53rebuilding the germinative layers of the
23:55epidermal layers and they continue to do
23:57this in around around the wound so these
23:59migrating epithelial cells will come all
24:01the way down to the base of the wound
24:03and they'll just grow and push up all
24:06the while you have more mass cells that
24:08are releasing um prostaglandins and
24:11other chemicals to cause cells to come
24:13to the area to clean up the infection
24:16and to regrow that dermis and that
24:18epidermal layer um macroasia are immune
24:22cells that will come to the area and
24:24they will clean it up so they'll get rid
24:25of um any of excess debris or microbes
24:29or anything that was in the area that
24:31shouldn't have been there and what
24:32you're going to be finally left with is
24:34what we call granulating tissue or Scar
24:36Tissue so fibroblast endothelial cells
24:39they kind of move in and they will
24:41produce the scar tissue or granulating
24:44tissue as a way of repairing the ingt
24:47and notice that even once the scab is
24:49gone sometimes it leaves a little bit of
24:52a mark there um because the anagement
24:54may not repair itself in the exact same
24:57way that it was prior to the injury this
25:00is also a good example of a short answer
25:03question because it's a stepwise process
25:06of what happens and I could ask
25:08something simply as explain how the
25:11integrate repairs itself be sure to
25:13discuss the role of mass cells
25:15macrofagos fibr blasts um and what is
25:19granulating tissue so and you should be
25:21able to tell me stepwise how that
25:23happens for your short answer questions
25:25I'm not really picky that you answer in
25:27essay form I just want you to give me
25:30all of the information I need to show me
25:33that you understand this process so if
25:35drawing it out and then labeling what
25:36you drew and um explaining in a short
25:40paragraph what you drew if that helps
25:43you to better visualize and explain the
25:45process and that's okay with me if
25:46writing it in bullets or charts or
25:49however you want to express yourself you
25:50have cre creative expression um to tell
25:54to answer your short answer questions
25:56the only thing that I answer is that you
25:58answer the questions fully and that you
26:00demonstrate that you understand the
26:02concept and this is for your lecture
26:04exams remember quizzes 15 multiple
26:07choice
26:09questions and then finally the types of
26:12injuries that we can have for the inment
26:15um these would be good questions for
26:17short answer questions as well to
26:19describe the different types of injuries
26:21to the inment and perhaps give an
26:24example of one so an abrasion is just a
26:26scraping away the superficial layers of
26:29skin or mucus so if you just scrape your
26:31knee um when you're riding your bite
26:33that would be an excellent example of an
26:34abrasion aeration is a jagged wound or
26:38cut so that is something where instead
26:40of just scraping your knee and just
26:42taking off that top layer of skin that
26:44you
26:45actually um cut deeper um into the integ
26:49down to the dermal layer perhaps so
26:51you've actually been cut um one year my
26:54dad we were in Texas we drove to Texas
26:56and he was trying to squeeze between two
26:58cars and he cut his knee on the license
27:00plate so he had a laceration which by
27:02the way he sewed up himself it was a
27:05holiday weekend and he didn't want to go
27:06to the emergency room so we went I
27:09forgot where we how we got this but
27:12somehow he ended up getting a suture kit
27:14and sewed himself up it was quite
27:16fascinating um a puncture is an injury
27:18that's caused by a sharp narrow object
27:20that's penetrating the skin I remember
27:22my little daughter Kira when she was
27:23about 5 years old she was upset because
27:26she had to go get a shot and she said
27:28they're going to puncture my skin I
27:30don't know where she got that
27:31terminology from but she was absolutely
27:33correct um because you it's a sharp
27:35neural object and that you know when you
27:37get an injection or vaccination that
27:39would be a puncture straight in and
27:41usually coming straight out um an
27:43incision is a cut produced by a surgical
27:45instrument notice that El laceration
27:48those are usually accidents an incision
27:50you did that on purpose because we're
27:52using a surgical instrument to create an
27:54opening so incisions we do those on
27:57purpose hopefully it's a healthc care
27:59professional that's making this incision
28:01and El laceration well those are more a
28:03cut but it's more Jagged and the edges
28:05aren't clean and those are typically
28:07accidents a contusion is just a fancy
28:10way of saying a bruise so an injury that
28:12does not actually break the ingent
28:14itself um but it causes swelling and
28:17discoloration and pain what we call AB
28:22Bru all right questions comments or
28:24concerns on any of that so far
28:33all right so I think what we're going to
28:35do
28:36now is just take a little bit of time to
28:43start the next chapter so I think we're
28:45going to go ahead and start um a little
28:50bit of the bone structure and histology
28:53so we're going to go ahead and I'm going
28:55to open up the next set of notes for us
28:58for
29:49for our next unit um in lab we're going
29:53to start to go over the the muscles and
29:55the bones um so this is is a good segue
30:00into what we will be doing on Monday um
30:03in lab or not this Monday in lab but the
30:06next Monday in lab so we're going to
30:09start talking about skeletal
30:14system all right so bone structure
30:18histology and articulations on here this
30:22is in chapter six but remember your page
30:24numbers are going to be a little bit off
30:27um if you have the the newer version of
30:29the textbook um but what you want to
30:31look for is that it's going to start
30:34with the introduction of the skeletal
30:35system so that what and I'm not sure
30:37exactly what the page numbers are in the
30:39new book I don't have the new book in
30:40front of me right now so your skeletal
30:43system like your ingt consist of two
30:46basic portions you have your bones of
30:49the skeletal system and you have about
30:52208 bones or 206 bones give or take some
30:55people have one more some people have
30:57one if few were
30:58um and then you also have what we could
31:00kind of consider accessory structures
31:01but you have your different types of
31:02cartilages ligaments and connective
31:04tissues all the types of cartilages that
31:07we find in the skeletal system um and
31:09connective tissues we've already learned
31:11about them in chapter 4 so that's what
31:12made chapter 4 so very important is
31:16because it laid the framework for the
31:18rest of the structures that we'll talk
31:20about because the rest of your organ
31:21systems are going to have in some degree
31:23or another epithelial cells and
31:26different types of connective tissues
31:28and once you understand those the jobs
31:30of those connective tissues and you
31:32understand the jobs of those um those
31:34different types of cartilages and
31:36whatnot you're better able to have an
31:38idea about how the different organ
31:40systems
31:41work so jobs of the skeletal system
31:45obviously for the support so the bones
31:46itself are going to provide the internal
31:48framework of the body or support those
31:51muscles the muscles allow the skeleton
31:53to move but it's the skeleton that gives
31:54that internal framework it also stores
31:57minerals and the bone itself and
31:59specifically calcium um there's the
32:01stored of fat or lipids in the yellow
32:04marrow on the inside or the medullary
32:06cavity of your long bones you have red
32:08Marl and it's responsible for uh blood
32:11cell production erthrocytes and lymoc
32:14sites um your bone also helps to protect
32:16various organs your heart lies right
32:19behind your sternum and your chest so it
32:21helps to protect that very important um
32:24organ as well as your rib cages help to
32:26protect your lungs and it also provides
32:28leverage for your muscles to contract
32:31again to provide that force of motion so
32:33all of these are examples of the jobs of
32:37the skeletal
32:39system the way that we classify bones is
32:42by three very basic categories we can
32:45classify them by shape we have bones
32:47that are considered long bones so the
32:49bones of your arms and your legs would
32:51be long bones um we can characterize
32:54them by internal tissue Organization for
32:57them whether they have um the what type
33:00of spongy bone or is it compact bone
33:03that's on the inside of it or we can
33:05classify Bones by their specific marking
33:07so some of their surface features that
33:09we find on them um we can consider that
33:13a way to classify them in our unit for
33:16lab two lab practical we will talk about
33:19framen holes and we'll talk about fosas
33:23um where they are shallow depressions
33:26and these are places where bones May
33:27articulate with other bones or some of
33:30these fan maybe where blood vessels and
33:32nerve um bundles can go through and by
33:35looking at those very unique markings
33:37we're able to determine one bone from
33:39another um we're also able to tell where
33:42the bone articulates with another bone
33:44so for your lab practicals it' be very
33:46important to understand um and you're
33:49going to have to know it for your lab
33:50practicals what are all these different
33:52little features on the bone and what do
33:54they mean those bone markings can also
33:56tell us the approx age and gender of
34:00skeletal
34:02remains so the primary classification
34:04that we're going to use in lecture for
34:06um classifying your bones would be based
34:09on shape so we have a long bone here
34:11this said before found in your um your
34:15limbs your arms and your legs so your
34:17femur would also be considered a long
34:19bone as well as your humoris we have
34:21flat bones that make up your skull so
34:23you have two parietal bones a frontal
34:25bone and an occipital bone and and you
34:28have um temporal bones in the side of
34:30the skull um you have sutal bones which
34:32are little teeny tiny looks like bone
34:34chips that are just embedded along the
34:36suture lines of your skull um irregular
34:39shaped bones would be like those of your
34:41inverte Brae all of your inverte Brae
34:43are sort of shaped alike one another but
34:45they're not shaped like any other bones
34:47in your body so we give them that
34:49classification of it regular um short
34:51bones such as in your your um
34:55carpal bones and your met carpal in your
34:58your feet and your carpal bones in your
35:00hands those are little short squatty
35:02stubby bones that we find there and then
35:05sesamoid bones um the most the best
35:08example of a sesamoid bone would be your
35:09patella over your kneecap and it kind of
35:11looks like an oversized sesame seed
35:14remember before I said people have about
35:16208 bones in their body some people have
35:19a couple more some people have a few
35:20less it's usually sesamoid shaped bones
35:23that they may have an additional bone in
35:25a joint somewhere
35:30so for long bones as the name suggests
35:32they are long and thin and as we've
35:34already established found in the arms
35:36legs hands feet fingers toes all of
35:38those places even though the fingers and
35:40the toes are shorter long bones they
35:41still have the same sort of
35:42configuration flat bones are thin and
35:45have parallel surfaces like we'd find
35:47for the bones that make up the skull
35:49your sternum is considered a flat bone
35:51as well there's a parallel surface of
35:53compact bone in the front and a parallel
35:55surface of compact bone in the back your
35:58scalpa uh and your ribs are like your
36:02shoulder blades back there um those are
36:04all considered to be flat bones as well
36:07Sutro bones remember we only find those
36:10um between the flat bones of the skull
36:12so you have their theye along the sutal
36:14lines of the skull and they're just
36:16really small kind of funky shaped little
36:18bones um along those sutal lines regular
36:22bones your vertebrae it's an example of
36:24that more complex shapes to them and in
36:27your third lab practical you all will
36:29tell me about those different fa facets
36:32those articulating facets that are on um
36:35those vertebrae your pelvic bone is also
36:37an irregular shaped type of bone um
36:40short bones small and thick wrist and
36:42ankle bones ssoid bones small and flat
36:46most prominent is your catella but they
36:48can also develop inside um near tendons
36:52um of the joints of hands and feets we
36:55said before if you have some folks have
36:5729 bones and sometimes they have an
37:00additional bone um an sesamoid shaped
37:02bone um in your hands or feet or any of
37:05those joints near those uh highly
37:08synovial
37:10joints so those bone markings that we
37:12talked about depressions or grooves um a
37:16depression would be like aosa is a a
37:19name for a depression or a Groove that
37:21you'd find in your bone and this
37:23discussion that we're having now will
37:25come back to it again when it's time for
37:28our um when we talk in lab class we'll
37:32talk about them again for unit two but
37:36um those depressions of those grooves
37:37are are certain types of bone markings a
37:40lot of those depression or grooves are
37:42places where blood vessels will go
37:44through um or you have bundles of nerves
37:46that can go through there you have
37:48projections that are also found of your
37:50bone um things that we consider like
37:53aile or an
37:58um fans or sort of tunnels where blood
38:01and nerves enter the bone so these are
38:02different markings depressions
38:04projections and tunnels these are all
38:06markings that we would find on the bone
38:10itself as we go through this chapter
38:13what I want you to notice is that the
38:15first thing and actually all of your
38:16chapters in A&P are kind of set up the
38:19same way using this Martini book that
38:21first we're going to take a tour of the
38:24organ system we're going to look at what
38:26types of structure are there what types
38:29of cells are there what types of in this
38:33case ligaments and tendons or whatever
38:35else it may be what are some things that
38:36we would see on this tour so if you ever
38:39like the Magic School Bus growing up or
38:41if your children still watch reruns of
38:43the Magic School Bus then you can
38:45appreciate this I'll be like uh what's
38:46her name Miss Frizzle Miss Fritz then
38:49I'm going to be your tour guide so we're
38:51going to look at all of these aspects
38:53and portions of the skeletal system of
38:55the organ system and then once we have a
38:57firm understanding of what these
39:00different parts are that make up this
39:02organ system then we're going to turn it
39:04on then we'll talk about exactly how
39:06these structures work together in order
39:08to achieve its function so next up on
39:11our tour is that we're going to look at
39:13a long bone and talk about how a long
39:15bone has very distinctive portions to it
39:19the first portion of the long bone is
39:20that it has that long shaft and we call
39:23that long shaft diaphysis so that Di
39:27like diameter means to go through so the
39:30diaphysis goes through and is the
39:32longest part of the bone itself so I'm
39:34going to attempt to draw this bear with
39:37me so this portion here this portion
39:42here that is our diaphysis that's the
39:45shaft of it the outside of this shaft is
39:49composed of very heavy compact for what
39:52your book also calls a dense bone but
39:54we're just going to use the term compact
39:55bone on the side of this shaft we call
39:58that the medullary cavity and it can be
40:00filled with different types of things
40:04and we'll get to that later
40:05on your epithesis on the other hand are
40:09the knobby parts of the
40:14bone so the wide Parts at each end are
40:19called your
40:24epiphysis and this is the point where
40:27the bone is going to articulate with
40:29other bones within this epithesis on the
40:33inside you have spongy bones so the
40:35spongy bone lies on the inside of the
40:38epiphysis OR at the ends of it um on the
40:41outside of it just like the shaft it's
40:43going to be covered with compact bone
40:47for the
40:50metasis it's where the epiphysis and the
40:53diaphysis meet
41:08so that's just going to be where they
41:10meet your metasis is also where your
41:13growth plates are found so that
41:15cartilage that's constantly um being
41:17converted into bone as you're growing
41:20that's at your
41:22metasis between your epiphysis and your
41:25diaphysis
41:31and here's a much nicer picture of what
41:32I attempted to draw um so we have the
41:35compact bone that's surrounding that
41:37empty or Hollow cavity that Central
41:40cavity that medullary cavity in there
41:42and then you have your epithesis on the
41:44end of it and they're filled with
41:45compact bone so this is an actual bone
41:48that we're looking at a
41:51longitudinal cross-section
41:55of now for flat bones like the parietal
41:58bones of your skull remember you have
42:00two of them you got a left and a right
42:01one they're going to be resemble more of
42:03a sandwich like configuration where
42:06there's compact bone on the top and
42:08compact bone on the bottom that would be
42:09like the bread and then the inside of it
42:11is going to be um what we call diploe
42:15diploe is a
42:19very high resistant form of spongy bone
42:22so this diploe will have be able to
42:25resist stress in mult M different
42:27directions so that's one of the reasons
42:29why it's pretty difficult to crack your
42:31cranium or to fracture your um parial
42:34bones or bones of your skull which is a
42:36good thing because you got a very
42:38important organ that lives inside of
42:39your skull um it's very difficult to
42:42fracture them because of this diploe
42:44this Diplo is able to withstand stress
42:46in many different directions and
42:48dissipate that stress over the Le the
42:50layer um or the surface of the compact
42:53bone to keep it from just breaking in
42:55one spot or fracturing
42:58beautiful picture of this we have a
43:00compact bone on top compact bone on
43:02bottom and then this diploe is basically
43:05like spongy bone on steroids so notice
43:07that the struts here are much thicker
43:10much wider um so that when Force hits
43:13compact bone the compact bone of this
43:15flat bone that force is going to be
43:17dissipated along the surface um of the
43:20compact bone as a result of this
43:25diploe so the type of tissue that bone
43:28is made of is we call it osus tissue if
43:31you remember from chapter 4 we talked
43:34about how bone is a type of well is it
43:38an epithelial tissue or is it falling
43:41umbrella of connective tissue
43:58bone is connective tissue so things that
44:01we know about connective tissue is that
44:03it has specialized cells it has um a
44:06fluid portion of it that ground
44:08substance and it's got protein fibers so
44:11for this osis or bone tissue there are
44:14because it is a dense supportive
44:15connective tissue um it has specialized
44:19cells that we're going to talk about
44:21they're four different classes of cells
44:22osteopor cells osteocytes osteoblast and
44:26osteoclast so those are the specialized
44:27cells that make up the bone it also has
44:30a solid Matrix of calcium salts so we're
44:34going to talk about the calcium salts
44:36that are in there not a whole lot of
44:37ground substances mostly protein fibers
44:41um that make it up and you have these
44:42calcium salt deposits and we also have
44:46protein fibers and the protein fibers
44:47that we find in this osis tissue are
44:50collagen fibers so so far in the
44:52skeletal system all we've done we
44:54haven't talked about exactly how any of
44:56it works we're just taking a tour of
44:59what you would find in the skeletal
45:01system so we've talked about how you'd
45:02find long bones flat bones regular
45:05shaped bones um sesamoid bones Etc we
45:08talked about how all of these bones are
45:10going to have some sort of marking or um
45:12configuration to them they'll have
45:14depressions or fosas or um
45:17epicondyles or fmen um tunnels or
45:20grooves they'll have all these different
45:22portions to them we haven't talked about
45:23what those things do but we just talked
45:25about this is what they are and we now
45:27we're starting to get down into a
45:29cellular level and say that yes bone is
45:31a type of connective tissue and just
45:33like all the other connective tissue
45:36it's got specialized cells ground
45:38substance and protein fibers ground
45:40substance and protein fibers make up the
45:43Matrix as we move further we're going to
45:45talk about the specific kinds of cells
45:49that are specialized and what they
45:54do so characteristic of this bone tissue
45:58that we're talking about very very very
46:01dense Matrix so what that means is that
46:05there's very little fluid that you would
46:08find as part of this connective tissue
46:10which makes sense that we shouldn't have
46:13a whole lot of fluid here because it
46:14needs to it's structured for support um
46:18osteocytes are the actual bone cells and
46:21the osteocytes which are in the Lacuna
46:24are going to organize themselves around
46:26the the um aversion Canal or the blood
46:29vessel that comes into the bone the
46:31cytoplasmic extensions that extend out
46:33from the osteocytes are called
46:36canaliculi um they form Pathways for the
46:39blood vessels so that the different
46:41osteocytes can communicate with one
46:43another and and all of this when I show
46:45you the picture of it we've talked about
46:47and seen in lab um and then you have the
46:50periostium Perry means around so the
46:52Peri and then osteum means bone so the
46:55per oium is going to cover the outer
46:57surfaces of the bone and that periostium
47:00has two portions to it the outside more
47:02fibrous portion and then the inside
47:05cellular
47:07levels so once again we're just taking
47:10the tour other aspects of that bone M uh
47:13that osis tissue so we've already talked
47:15about some of those specialized cells
47:17the osteocytes would be those
47:18specialized cells and then we just
47:20talked about the parts of those
47:21osteocytes how they have the canicula um
47:25that mies up their cytoplasmic
47:27extensions and how they're able to
47:29communicate with one another and we
47:31talked about the surrounding the fibrous
47:34uh connective tissue that surrounds the
47:36bone itself with that periosteum now
47:38we're going to talk about the Matrix of
47:39the ground substances and the protein
47:41fibers within that Matrix most of it in
47:44fact 2/3 that's a number I want you guys
47:47to remember is called calcium phosphate
47:50that calcium phosphate reacts with
47:51calcium hydroxide to make hydroxy aetate
47:55um this hydroxy aetate is what
47:57incorporates those calcium salts and
47:59those other ions and it helps to give
48:01the bone its strength to make it nice
48:03and strong and hard a very cool segue
48:08here or connection is that in chapter
48:10five we talked about how Vitamin D3
48:13helped with calcium and phosphate
48:15absorption this is the
48:17calcium phosphate that we're talking
48:20about that is absorbed in the skeletal
48:23system as a result of vitamin D3
48:27the proteins that make up this Matrix
48:29are going to be collagen fibers 2/3 of
48:32the bone matrix this is calcium
48:34phosphate onethird of the bone matrix is
48:36just these collagen fibers so the job of
48:39the collagen is to kind of give the bone
48:41a little bit of give if you will so it
48:43doesn't make it so super super brittle
48:45without the collagen fibers the bone
48:48would be very very brittle and would
48:50break or fracture or shatter very easily
48:54it is a collagen that helps it to have a
48:56little bit more um bounce or give to the
48:59Bone so that it doesn't shatter upon
49:01impact all the time the calcium
49:04phosphate its job is to make sure that
49:06the bone is nice and hard if the bone
49:08was just consisting of only collagen
49:10fibers it would be very floppy um and
49:14very flexible but it wouldn't be able to
49:15withstand a lot of body weight so both
49:18portions of the Matrix are equally
49:21important one3 collagen 2/3 calcium
49:24phosphate
49:31other cells that make up the bone so we
49:33have those specialized cells remember
49:35connective tissue three parts to it
49:37you've got ground substances protein
49:39fibers both of which we've talked about
49:41and then you have those specialized
49:42cells one of those specialized cells we
49:44talked about were osteocytes these
49:47specialized cells only make up about 2%
49:49of the bone mass itself but we have
49:51osteocytes which are the actual bone
49:53cells um osteoblast these are the bone
49:57building cells those osteoblasts can
49:59become osteocytes osteoprogenitor cells
50:02are your stem cells that can become
50:05osteoblast and osteoclast these are what
50:08I like to call the bone crashing cells
50:11these are cells that will liberate
50:13calcium and put them into the
50:14bloodstream if your calcium levels get
50:17too low so osteoclast will break down
50:20osteocytes osteoblast will build B for
50:23build B for build blast will build Osteo
50:26ites and osteocytes were they're just
50:29the bone cells that we find with Kuli
50:33around the central Canal of compact
50:37bone so osteocytes are your mature bone
50:40cells um they live in the Lacuna and we
50:43talked about a lot of this in lab so I'm
50:44not going to spend a whole lot of time
50:46on it um they are between what we call
50:49lame layers they have canicula that will
50:52extend to con communicate with the other
50:55bone cells and and a very important
50:57feature of osteocytes they don't divide
50:59when it's time to make a new osteocyte
51:02an osteoblast will be triggered through
51:04hormones and various other entities to
51:08become an osteocyte the osteocytes don't
51:10continually divide um jobs of osteocytes
51:14are to maintain the protein and mineral
51:16content of the Matrix and also to help
51:18prepare damaged bone when osteoblasts
51:21become
51:24osteocytes osteoblasts are our bone
51:26building cells B for Builders B for
51:29blast um they secrete an organic Matrix
51:32that we call osteoid and the osteoid
51:35that's produced by the osteoblast kind
51:37of En circulates that osteoblast until
51:40um calcium and phosphate comes to fill
51:43in those areas or deposit it into that
51:46osteoid um as an osteoid is primarily
51:48made out of collagen fibers um so the
51:52hydroxy aetate and those calcium
51:54phosphate minerals will um calcify
51:58around the osteoblast and as that
52:01happens as it becomes surrounded by bone
52:03the
52:05osteoblast becomes an osteocyte so
52:08osteoblasts are your bone building cells
52:11because if if you will remember
52:13osteoclasts don't divide or I'm sorry
52:16osteocytes don't divide so when you need
52:18new osteocytes you have to build them
52:20from the
52:22osteoblast Osteo progenitor cells are a
52:25special Ty of mes kimal stem cells which
52:27we've already discussed how methanal
52:29stem cells are a one of the nine cell
52:31types that you can find um in connective
52:34tissue um they divide and become Osteo
52:38blast where we find Osteo presentator
52:40cells are in the osum or the inner layer
52:44um the the inside portion of the bone
52:47indes stum um itself and the inner
52:51cellular layer of the periostium the job
52:54of the osteop progenitor cells is to
52:55repair a fracture because the
52:57osteoprogenitor cells produce oste oblio
53:00Osteo blo secrease an osteoid Matrix
53:03that eventually gets filled with these
53:05calcium and phosphate mineral deposits
53:07and as that area calcifies those
53:09osteoblasts then graduate to become
53:11mature osteocytes so that's how the the
53:14osteoprogenitor cells becoming
53:16osteoblasts who become osteocytes that
53:18is that whole process of assisting in
53:20fracture
53:22repair and then our last type of bone
53:25cell are Osteo class
53:27osteoclast are going to be the bone
53:29crashing cells C for crashing C for
53:32class they're going to break down and
53:35they secrete acids and protein digesting
53:37enzymes to dissolve The Matrix and
53:40release the calcium and the phosphate
53:43that's been distored um on the outside
53:46of these Osteo these mature bone cells
53:48and we call this process osteolysis the
53:51stem cell that osteoclast come from is
53:53completely different from that
53:55mesenchimal stem cell that osteoblast
53:57arise from or Osteo progenitor cells it
54:00comes from a different stem line than
54:02let's just go back this guy this is in
54:04the stem cell that produces the
54:06osteoclast the stem cells that
54:09osteoclast arise from are more like
54:12macras because they have this digestive
54:15um Quality to
54:19them so there is a fine balance between
54:23bone building and bone breaking so the
54:25bone building by osteoblast and Bone
54:28recycling by osteoclast there's a nice
54:30balance between them if you have more
54:32breakdown than you have building if you
54:34have more crashing than building then
54:37obviously the Bone's going to become
54:38weak and things that can cause that are
54:40poor diets um malnutrition and age it's
54:44something that just sort of kind of
54:45happens to a lot of people as they get
54:47older however exercise specifically
54:50weightbearing exercises is going to
54:52stimulate more osteoblast activity in a
54:55nutshell what happens is that when you
54:57engage in weightbearing exercises it's
55:00telling your body that hey I need this
55:03this bone to have more uh width to it to
55:07be able to withstand more pressure to
55:09withstand more weight and so it causes a
55:12bones to become thicker what we call
55:14oppositional growth um it becomes a lot
55:17thicker as a result of these
55:18weightbearing exercises so it's kind of
55:21um your body's way of saying well if
55:23you're going to be doing these tort of
55:25exercises I better make sure that I
55:26prepare for it and over time you'll see
55:28more osteoblast activity happening to
55:31build the bone um outward not longer but
55:34outward so that it can withstand these
55:36different types of um exercises and
55:40routines all right so that's where we're
55:43going to end for today so everything
55:46that we've talked about for today's
55:48lecture for last Wednesday's
55:52lecture and last Monday's lecture on
55:55August 31st
55:57that's all game for your quiz that
55:59happens on
56:01Monday all right so I think that's a
56:04good place to end questions comments or
56:06concerns about
56:10anything all right well enjoy this
56:14wonderful Wednesday it's a little rainy
56:15outside but we needed a little bit of
56:17rain um and I hope you guys had a really
56:19good three-day weekend hope you did
56:21something fun as like the last blast of
56:24Summer and I will see you guys on Monday
56:27well prepared and remember um for your
56:30worksheet that's due on Monday as well
56:33um for part e couple of hints to that a
56:36there can be more than one answer um and
56:39for part four e uh four a through I
56:42think it's j that when we're talking
56:44about animals we want to use the terms
56:46ventral and dorsal
56:49um for the cat question so that might
56:52help and if you still have issues come
56:54see me in my office hours or shoot me an
56:55email um and we'll see if we can't get
56:57it worked out um through that I am in a
57:00new office right now so I have a new
57:02office phone number and the extension is
57:057713 if you want to call me if that's
57:07better for you um to call me during my
57:09office hours new extension 7713 if you
57:13want to talk about your um lab worksheet
57:16for the other parts of your lab
57:17worksheet like labeling those organs and
57:19labeling the hystology if you use the
57:21images that are on blackboard for
57:23hystology and you use your textbook as a
57:25guide they'll that's more than
57:27sufficient for a key I think it's just
57:28that very first part of the lab um
57:31worksheet that people kind of had a
57:32little bit trouble with answering those
57:34questions
57:35properly all right so if you guys don't
57:37have any other questions comments or
57:40concerns enjoy your day and I'll be
57:43talking to you soon
57:55bye for