mesenteric fat

[music] hi guys and welcome to csun's biology 101 pig dissection video my name is stephanie and i'm gonna be helping you through your pig dissections for today. so let's start with the materials that we need to get started, okay! number 1: our pig dissection manual.

so you guys should have already purchased this from the bookstore. and every single person really needs to have one of these because they're great study guides. so you really need to have your own pig dissection manual. number 2: your vocab list. so your ta should have already providedyou this. and this basically breaks it

down into the sections, so you got external anatomy, cheek dissection, circulatory system, and then reproductive and excretory systems. and basically this is our study guide. so you should use this as a guideline as to what you're going to study for the final. so all of these terms could potentially be answers on your final.

so what you want to notice is that next to the term there are page numbers and diagram numbers, and this refers to your pig dissection manual. so you always want to refer to the this and make sure you're checking things off and making little notes, but also referring back to your manual so you know exactly what you're looking for.

now we have broken this down into day 1, day 2, and day 3 this is a rough guideline of what you kind of want to accomplish on each of those days. now mind you this is a 3 hour, study-at-your-own pace kind of lab. so you have 3 days to go through this entire list and get everything you need

done and review and take pictures. we actually highly recommend that you take your own videos and that you take your own pictures because that will give you an excellent study guide of what your pig actually looks like instead of just examples off the book. all right, next what you'll need is your dissecting kit, and this dissecting

kit again you can purchase at the bookstore. but you can share this between buddies so each person, each pair of people will get one pig, so you and your buddy can actually share this dissecting kit if you'd like to. you really don't want to share your manual but it's okay if you want to share your dissecting kit next up, you will need goggles. so you

need the goggles that will completely cover your eyes. so that we can see here that we are covered, and we don't want anything splattering up at us, which would be kinda gross! so in our dissecting kit that you guys have purchased at the bookstore, we have several different tools. so you have a ruler, you have a probe scissors, tweezers, and a scalpel

you also have tiny little pins. and these pins are really useful for pushing down other parts of the pig or moving stuff, again, this will press nicely intothe wax bottom that we have on the bottom of our tray, to keep them nice and straight up so let's talk a little bit about our tools. so this is a probe. so this is basically a very fine tipped picking-tool.

and so what we want to do is we want to pick through the membranes. if i have a thick membrane like this, you almost want to scrape throughthis. and it will actually start breaking up those really thin membranes. and now this is a great tool because you actually don't have to cut anything, you don't have to press down. so this will actually help you clear away those areas to expose your organs that

you're trying to get to and identify. next up is our scissors and our tweezers. now remember one person should pretty much be doing the dissection at all times while the other person takes notes, takes picturesetc. so what you always want to do is you wantto lift up with the tweezers, and you want to cut with the scissors. now this is basically to remove layer by layer

so you don't end up damaging anything. so we can lift and then cut right at thisconnective tissue, and we're gonna lift again and cutright at that connective tissue and we're gonnaslowly peel layer by layer away. and this will helpnot to damage any of the organs underneath or any those thin vessels like arteries and veins that you can easily, easily cut through. so the last tool is our scalpel.

probably most of you are very familiar with the scalpel. and you guys all want to play doctor. but this is actually not a very good tool to use. not in our case. so the scalpel can actually be very dull, and what you have to do is that you'll actually have to press down quite hard to actually break into anything. now you can't stop or control how deep you go in with the scalpel.

and so this can actually damage those organs and those fine vessels that we were talking about. so unless you're breaking bones, you want to avoid using the scalpel. and again, you're best friend will probably be the tweezers and the scissors. so we're going to lift, and cut...lift and cut. right at that connective tissue. and again, if you go nice and slow, you won't end up damaging any of those

organs that we're looking for. next up, is gloves. so we will be providing you guys gloves. but you never want to leave the classroom with the gloves on. you can potentially contaminate things outside, so you always want to take the gloves off and throw them away before you leave the classroom for any reason. with that, please use the gloves sparingly. they do cost a lot of money if we keep buying them over and over again. so go easy on the gloves.

next up are our goggles. you want to make sure that they're the type of goggles that fit securely on your face. and they actually cover all of your eyes. so you don't want any of those stick lenses ones, that can actually get stuff in between. so you want to make sure that they will completely cover your face. so the next thing you are going to get, which the ta will provide you again, is this bag. and this bag

is actually going to have a little tag in it and strings. you don't want to throw any of this away. so you want to keep the bag, you want to keep the tag. and you want to keep the strings for all the 4 weeks of your pig dissection. so, we're gonna set this aside. and the very next thing that you guys are gonna do, is your gonna go and get a tray. so this is again, the same tray for each pair of partners. and you're going to go get your tray and then,

in the corner, in the fume hood, you're going to get your pig. and we've got our cute little fetal pig here. and, you can see he's kind of sitting in this 'liquidy' mass. so the very first thing you're going to do when you get your pig, is you're going to cut a little hole in the bag, and you're actually gonna dump this liquid out. and this liquid does not go down the sink! this liquid goes into our receptacle, which i will show you in just a second. so now that we've gotten our pig, we've grabbed a tray, and we've gotten our fetal pig.

so you can see the fetal pig comes in this bag and it's got a lot of extra fluid here. so what we want to do is instead of opening that, and letting that pour all over our tray, we want to get rid of that right away. so you want to grab a pair of scissors and just cut a small, little corner so that you've got an opening in your bag. like so and then you want to hold your pig firmly and then pour the juices into the bucket labeled "pig juices"

so animal juice, excess animal juice in this bucket. this is the bucket you want to pour your juices into. and you're going to notice that in the fume hood where this bucket is there're two other buckets. those buckets are also labeled: "pig parts" and "pig parts on paper towels" so again, you want to know which proper bucket you are putting this stuff into. so, when you bring your pig back to your tray,

what you want to do is then cut the bag completely open. like so you want to get rid of this bag because we are no longer going to be storing the pig in this bag. and again, any extra juices go back in the bucket. and then the plastic bag can just get thrown into the regular trash. so now we've got our pig. we've placed him on our tray. and you don't want to tie him up just yet. and by tying him up, i'm referring to the strings that you find in our bag.

so each pair of partners is going to get this little bag which comes with a tag and comes with strings. do not throw away the bag, the tag, or the strings the entire time. because this is the only bag and strings you're gonna get so the prep lab will not give you any more strings so please do not throw anything in this bag away. so what you're going to do is you're going to open your bag, you're going to set the tag aside, and you're going to grab the strings.

you want to place the strings aside for just now because we're not gonna tie him up yet. but what you do want to do is you want to start looking at his external anatomy. so we want to determine first off if it's a male pig or a female pig. and that's actually really east to do. so most people look at the stomach here which you can see on the bottom side of the pig. and you see all these tiny little bumps. these little bumps are papillae. and these specifically are "mammary papillae"

which means they are basically nipples. so that is the equivalent, mammary papillae. so papillae just means, like i said, a little bump. and so automatically a lot of people are going to say okay well it has to be a female pig because she has mammary papillae. well, at this point, you can actually point around to any guy in the room, and say, "he also has mammary papillae". so, that is not a good indicator of if it's a male or a female pig.

so we also notice right here this little flap that is poking out of the stomach this is his umbilical cord right here. and this is where the fetus attaches to the mother. so this is where he gets all the nutrients from. so what you want to do is to lift this up, and look underneath. in a male pig, the urogenital opening would be right about here, just underneath the umbilical cord.

there will be a little tiny hole. and that's his urogenital opening. but in females, it's actually all the way here in the back. what you notice if you lift the tail up, and right underneath the anus, is this little bump. and this is another papilla. again, "papilla" just means a little bump. so we've got this little papilla. this is her "genital papilla". because it is covering her urogenital opening.

so you can actually see, there's a tiny hole, right there. and that is her "urogenital opening" so once again, in males the male urogenital opening is going to be right under here, under the umbilical cord. and the female urogenital opening is going to be back here underneath the tail. males do not have a genital papilla. so this little indicator, this little bump right here.

it's her genital papilla. and that's the first indicator (and the easiest indicator) of telling the difference between a male and female pig. okay, so now we're going to actually start cutting into our pig. so the first section on your sheets, after external anatomy, is cheek dissection. so i want you to follow the instructions in the book. and i want you to read them, but we're going to modify them a little bit.

the book does have some good techniques, but i also have some good little short cuts that will help as well. so, since our pig is already open, all of your pigs should have this incision towards the chest and the neck area. this is basically because they inject the arteries and the veins with dyes so you can tell the difference. so the blue is always going to be veins, and the pink is always going to be arteries.

since we have the nice big incision already, and we can kind of look inside the pig, that's exactly what we're going to do, is where going to start there. and kind of cut some of this connective tissue, again, just underneath the skin, just at the connective tissue. and we're going to start peeling it away. so what i'm doing is i'm lifting and cutting. very, very shallow

so i'm looking into the pig i'm moving my tweezers so i can maximize the lift and see very clearly what i am cutting. you never want to start cutting straight down because you never know what you are going to cut. and especially around this cheek area, there's a very thin nerve called the "facial nerve" and a lot of people end up cutting that off.

the good thing about the pig, is that they have two cheeks. and so if you've messed the first one up you can always go and cut the other cheek up. that's fine. but if you go nice and slow, you shouldn't ever cut anything away that is needed. so again, we're lifting, cutting away at that connective tissue, watching where we're going. don't worry about these tiny little veins and stuff.

so we're just peeling away that skin. once you get a nice flap of skin, you want to cut that off, and get rid of that. we want to see what we are doing. so you always want to make it as clear as possible. so again, we are going to go up towards the eye. lifting cutting at this connective tissue always moving around the tweezers, where you need them

and again, always the same person lifting and cutting. you can't have your partner lifting and you cutting. this needs to be a coordinated effort. and so it's really best if only one person does it. but you should definitely take turns. you should take turns cutting through these guys. and really experiencing the dissection, because it will help you remember. because, if you remember, "ah man, i cut that gross cheek open."

then it will stick with you, and it will actually be easier to study for your final. we're gonna lift this away. cut some of this away. [scissor-clipping noises] ok....so.... now when we've got this thick membrane stuff, which you can see right here. this scrape tool is actually really, really handy in picking away this membrane without damaging any of the organs.

so you want to lift this neck muscle away all this fatty neck tissue in here, this is your "parotid" so this all this fatty neck tissue that surrounds the neck right here. and that's for protection for the pig. so what we want to do is that we want to remove that. and you can actually see the picture in your book of the tool being pulled away.

so all of this parotid being pulled back to expose the organs that are underneath. so we want to get through this parotid so all of this fatty, 'glandy' stuff, this is all parotid gland. so glands are either going to look like fatty tissue, or they're going to look like little beans. so in this case the parotid gland looks like fatty tissue. you can see this big, round, circular muscle right here,

that is your masseter muscle so that controls the jaw. this is your big, big cheek muscle. now if you carefully pick away some of this membrane towards the top of the masseter muscle, you can see this very thin, almost 'whitish' little tube this guy right here, going all the way across the masseter muscle, this is your facial nerve right here.

so a lot of people cut will cut this away, if you go too deep. so you want to be very careful. you want to remember that the one at the top of the masseter muscle that's going to be your facial nerve. alright, so we got again, this is your parotid gland, so this parotid gland actually leads into it's own little tube underneath the cheek. so the line going across the masseter muscle is the facial nerve,

this line, going underneath, right here, it feeds in you can see this blue and white line coming here and it leads into all this parotid stuff here. that is going to be your "parotid duct". so just remember, even if you cannot see it very well in your pig, or perhaps you've cut it away, if we're talking about pinning the line up here,

it's going to be your facial nerve. if we're putting the pin here, it's going to be the masseter muscle. all the way over here in this fatty neck tissue, that would be your parotid gland and, again, this little 'tubey guy', right down here, that's going to be your parotid duct. now, if we remove some more of this, parotid gland and, again, this is all just fatty neck tissue

so i know that i'm not going to hurt anything. you guys want to be a little bit more careful than this. once you remove all of this, kind of pull this back, what you are going to expose, is this little gland. and, again, glands can either look like little beans, or they can look like fatty tissue. so whereas the parotid gland looks like fatty tissue

the "mandibular gland" which is this guy right here, he looks like a little bean. so you can see this tiny organ right here. this guy. he looks like a tiny little bean. it's to the right, or right behind, the masseter muscle. so...review... masseter muscle.

facial nerve, this tube. parotid duct...leads into the parotid gland, all this fatty neck tissue. sitting behind that...the mandibular gland. this guy, right here. and that, is everything in the cheek! so this is the way you want to tie up your pig. and here's an example of what we're going for. so you want to wrap the string under the tray,

and back around to his other leg. i find that with the legs, you want to do it just above the knee, because it really solidifies it. and i usually tie a knot on one side and then wrap it around on the other. so let me show you what that looks like. so remember that this is the string that was in our bag, and we never throw away this string so even when we're done today,

we're not going to get rid of this string. so you want to wrap it underneath, wrap it around his wrist in a little knot. remember, these pigs are already dead... they're not going to go running away. so i usually wrap it around in a knot and then kinda like that. and then you want to pull him taut, ...taut, or very, very tight.

so this basically means there's not a lot of slack here. you don't want him flopping over. the whole point of tying him is to make him nice and open, so that we can work, without getting interrupted. so then i just wrap, and wrap, and wrap, like that and he should stay, pretty good. okay! nice and taut. so, we're going to continue on, from where we cut in the throat,

and we're going to start clearing away this area, and getting to the larynx and the trachea. so, this part, right here, if you feel right in between the arms, it's going to be this hard, like, bone, this is part of your breastbone, right here. so you want to avoid cutting this area for today. we're gonna work on this next week, when we do the circulatory system. but for today, we kind of want to avoid this area,

so right in between the arms, there's a lot of veins and arteries, and really important circulatory stuff right there that we don't want to cut today. so what you want to do, is you want to kinda of feel, and press with your finger, just north of that, is a fleshy area. and that's where you want to start cutting. so, again, we're going to be moving layer-by-layer,

and i'm going to be looking, into the pig, as i do this. so i'm looking under the skin, to determine what i'm cutting. 'cause there's not gonna be a lot in the throat that you can cut away, until you get past this muscle. so it's okay to go a little, tiny bit faster here, and again, never go straight down, you always want to cut side-ways.

if you go straight down, you're going to start cutting things, next thing you know, you're going to cut away your larynx, and that's not what you want to do. so we're going to remove all this parotid. this again is all just fat, and tissue. we'll remove this nice and slowly. [scissor-clipping sounds] ...get all that. and then you can kinda see that it kinda opens up a bit. so after we've gotten all that fatty tissue,

this opens up kinda of nicely. so we're gonna remove this fatty tissue. remove these. this right here, is actually part of your thymus. so this, right here, is part of your thymus, that sits on top. we typically don't test right there for the thymus, we usually test over the pericardium for the thymus. so it's okay to cut that thymus away. but if you're wondering, that's what we're cutting.

okay... we start to get a little bit deeper... ...a little bit deeper. clear this nicely up. and then here is where we start to use our probe again. so this is all membrane, that we want to get rid of. so we're going to lift, and scrape... lift, and scrape. now, in your book,

larynx and trachea are listed in two different places. they're listed on page 45, but they're also listed again on page 78. and i always find that page 78 is a little bit more helpful. we're just going to be removing this stuff. now you see this big ball on the throat that we've gotten to, big, giant ball on the throat, that's your larynx. that's your voice box, right there. so you don't want to cut into that,

you certainly don't want to cut any further than that. and at the bottom of that, we've got our thyroid gland, which we also don't want to cut away. so here's where you have to start being a little bit more careful. so the pick is really good at not being able to cut organs, but really good at being able to removing this membrane. so, scraping... clearing, scraping...don't go too deep! okay!

there we go. so now what we can see here, is we've got, larynx: big ball in the throat. leads down to this bumpy tube, if i can clear some more of this membrane away. there we go. see this bumpy tube, that's your trachea. so larynx, trachea, and then sitting on top of the trachea,

you've got this little thyroid gland right here. again, glands are either fatty tissue or little beans, this guy is a little bean. so larynx is a big ball in the throat, bumpy tube is the trachea, little bean sitting on top of the trachea, that's your thyroid gland. so the next part we're going to move on to, is the mouth. so once we got done with the cheek and the throat,

we're going to actually go in and start working on the mouth. now what's really important here is that a lot of people, when they start cutting the mouth...because you have to, basically, "joker" him, and cut both sides of his mouth down. a lot of people will go straight into the mandibular gland. and so this area typically gets ruined. so you want to make sure at this point that you have taken all the videos and pictures that you need to study. so this is one time that we let guys and encourage you guys

to use your cell phones (not for facebook), but for pictures and videos. so take pictures of this. (you know) point at this...tell me what it is. point at this...tell me what it is. and record what it is. because later on, when you're going back and studying, you won't have these pigs in front of you. you'll need to go back to your pictures and videos and study from those. so i highly encourage that you get all of this area completely taken, all the pictures that you need to, and you've really got that solid before you move on to your mouth.

so, with that said, if we're totally ready to go, we've taken all of our pictures, we're good, what we're going to do is, again, we're going to "joker" him, so you're going to cut down the sides of his mouth. and the whole time, you're going to be trying to open his mouth. so he's going to go from this, to about this. so he's going to go completely flat, so you really have to follow down the throat,

instead of into the head. and i'll explain what that means. so this is really the only time that you want to use your scalpel, because you are going to be breaking bones, and you're going to be breaking the jaw bones, here. so, two fingers should be trying to open the mouth, or three fingers...however you want to do it. and what we're going to do is cut not into the brain, but down the throat. and that's where a lot of people just start cutting, cutting, cutting, and they actually start cutting this way. and then take his whole head off! and that's not what we want to do. we want to cut down the throat.

so i only want to cut into those bones, and you can hear them break, just like that, and these guys are pretty soft, so it should go right through. so i want to start following the throat, not into the brain. so now on this side, if you want to try to preserve this, there's a way to do it, you got to kind of cut high, and then around. so i avoided the masseter muscle,

i avoided the facial nerve. and i kinda cut up towards his eye, and then back down. so inside the mouth, it's gonna look kinda like this, and we want to cut only these bones, and help us get down the throat. ...another one... you really want to be careful here, you don't want to stab in, and then cut yourself.

i've actually done that before. and it's not fun! you want to be very careful when breaking these bones. and they are pretty soft. they should break pretty easily. you want to make sure that you're cutting the right ones. again, i don't want to keep cutting into his head, i don't want to cut down. i want to be prying the mouth open, so that you can get down into his throat.

so cut off what you need to, to get down into his throat. [bone/tissue breaking sounds] you can hear those little bones breaking. alright, almost there. [tissue-cutting sounds] okay... cutting on both sides ...there we go. a little gruesome, i know, but there. once you get all the way down,

and you see, this little flap, right here, that's when you can stop cutting. so, now that we've got all the way into his mouth, let's talk about the parts of the mouth. so, these tiny little bumps on the tongue, remember little bumps means "papillae" or "papilla". so these little bumps are the tongue papilla. ...or tongue papillae.

and then you've got his tongue. and then you've got all the way down here, these are also tongue papillae. this is your soft palate here, you can see this is the back of the throat, or the top part of the mouth. it's nice and soft. you can push it, it's kinda and squishy. and this here is your hard palate. these ridges here, that go all the way across... this is your hard palate. and you can tell because it's very, very hard.

as soon as it starts to get soft again, this is your soft palate in through here. alright. so... this tiny little flap, right here, is called the epiglottis. "epi" means "on top". so, basically, on top of the glottis. so, this tiny little hole, that the flap is covering, goes into the tongue, almost...

it actually goes down the throat, but it looks like it goes into the tongue. and that is your glottis. so this, where the probe is right now, that's in the glottis. so on the test, if we were to pin it here, and go straight into the hole, that would be the glottis. but if we were to pin it sideways, through just the flap, that would be the epiglottis.

now this main hole, that goes all the way down the throat, here...this is your esophagus. and this is where. [sneeze] bless you! this is where the food goes down. so the food enters the body through the esophagus. so the major hole going all the way down the throat is the esophagus. and then this passageway going up, almost into the soft palate, this is going to the nose..."naso", nasopharynx.

so this passageway, up in here, this is your nasopharynx. so one more time: tongue papillae, soft palate, hard palate, this is your epiglottis, covering the glottis. if i were to pin it here, that would be the epiglottis, oh, sorry, here would be the epiglottis.

in the hole, would be the glottis. all the way in the throat, would be the esophagus. and up toward the nose, nose, "naso", nasopharynx. and that, is the mouth. the instructions give you very, very clear details. and it's in your...it's in your manual on how to cut depending on your sex. so if you're cutting a male pig, you're going to cut a certain way. and if you're cutting a female pig, you're going to cut a certain way.

so i'm going to start with the female pig right now. really the most important part is to cut around the umbilical cord. so we want to leave the umbilical cord completely attached, and then we can just cut everything else all around it. that's not a problem. in case we open this guy up, and there's a lot of excess juices, or gross stuff, what i want you guys to do is before it gets all over your tray and gets really gross, take your pig back over to the "pig juice bucket"

and pour it in there. and if you need to rinse off your pig, like if the stomach is opened up, (it's not as gross as it sounds) and there's stuff in there, what you can do is you can put a little water inside you pig, squish him around, and then pour all of that juice into the juice bucket. not into the "pig bits" bucket, or the "paper towel" bucket but the actual "pig juice" bucket.

and so if you need to rinse off your pig at any time, you can do that, and then pour all of that liquid never ever, ever in the sink, always into the bucket marked "pig juices". alright. and with that, let's get started. so we have our happy pig tied up. we've already done the cheek, the throat, and the mouth. and now we're going to move on to the body cavity. remember, we're going to avoid this area right here.

this is where that breast plate is. this is where his ribs are. this is where all of his important circulatory system is. so we're going to avoid that. now the book has you starting incisions, like one...and two... and three, and four, and five and six... if you'd like to follow that, that's absolutely fine. there's nothing wrong with those instructions.

i find that they take a little bit longer than is necessary to open the body cavity. so what's important about the body cavity, is that it's surrounded by a diaphragm. so in acting, they say, "breath through your diaphragm". you know. and you're supposed to increase your breath through your stomach. and that's because you can actually fill this entire cavity up with air.

so your organs are not covered in "guck", and it's not garbled around in there. it's actually very neat and organized. and nothing's really, attached. at least, not the skin anyway. so what i do is i usually come over here to the side, and you can already feel it. if you pinch the skin right here, there's really nothing behind it. it's just skin.

so what i'm going to do, is i'm going to feel this right here. and then i'm going to poke that through, be sure not to poke yourself. because i can feel that there's nothing between here and that little, probe. so then i'm going to lift this up, and i'm going to cut. just like so. so what you can see is if you look inside the pig,

you can see the diaphragm. so this thick membrane, right here, underneath the skin, that is the diaphragm. so if we start to pull this away, and cut this away, [scissors-clipping sounds] you actually expose the diaphragm. so this is why i always pinch that skin, so i can feel that, oh, there's nothing important in there.

i'm not going to damage anything, if i cut through it. what i want you guys to do is before you actually break into the body cavity, is to get a good look at the diaphragm. so it's the thick, muscular, layer, that surrounds this whole bottom body cavity. so that's the first thing on your list, the diaphragm, right here. now, if we were to puncture through the diaphragm, and remember, the diaphragm is fairly thick,

and so we were to puncture through... [tool clanking noise] [scissors-clipping] you cut all that open, what you notice, is that it opens up into, like, a cavern. so now there's nothing attached. the skin is not attached at any kind of membrane. and that's why you always want to pull everything to the side. because you don't want to go deep down.

you never want to go deep down because you'll cut up organs and stuff. so if you pull all the way to the side, you can look, and see that there is actually nothing attached. so, i can cut around, this and not damage anything. and then you open it up, and you've got a nice open hole, into the body! so now, you can look and lift around and be, like, okay well, there's nothing here i'm going to cut...there's nothing here i'm going to cut.

and you can start making slightly larger incisions. you will have to break some bones over here. these are ribs. but they usually cut off pretty easily. again, cutting...cutting...cutting. so this is our umbilical cord. we want to avoid that, because we've got a female here. so we want to cut a nice circle, around her umbilical cord, and cut all this excess skin away.

and, remember, we're always removing excess skin, because if it doesn't need to be there, it's just going to get in our way when we're trying to look at stuff. [clipping sounds] so we're cutting all this away. so this is what i mean about that "gross" stuff on the inside. so we've got a little bit of food, that's probably leaked out... a little bit of dirt. and some of that liquid again. so we can pour all this out.

and, if it really bothers you, or gets gross, what you can do is put some water in your pig, swish it around, and then try to get this stuff into the pig juices bin. so that's what i mean by that gross stuff on the inside. so then we keep cutting... all the way to the other side. again, there's nothing that you're going to hurt, as long as you don't go too deep. again, you can kinda see the thickness here.

that's your skin on the outside, and then, this thick layer, this darker layer on the inside, that's all your diaphragm. surrounding the whole cavity. okay... and then we can probably remove some of this excess... skin from around the umbilical cord. we just want to make sure we don't damage her reproductive organs, because we're going to take a look at that in two weeks.

so all these fleshy bits, we just want to remember, these are the "pig parts" this will go into the "pig parts" bucket. and not the "pig juice" bucket, and not the "paper towel" bucket, but the "pig parts" bucket. very carefully... we want to cut that. okay.

alright! so then what you see, if you see that our umbilical cord is actually attached. it's attached down here with these arteries. remember, pink is arteries. and then, this is our urinary bladder. and this goes up to the umbilical cord. and this is where the urine is stored. but we're going to talk about that in a little bit. what's the first thing i want you guys to do, is once you've got this nice, open cavity, is i actually want you to cut this blue...vein right here.

so this leads from your liver, to the umbilical cord. so this is our umbilical vein. so that's on your sheet, as "umbilical vein". so you can see that you can't really get by...you can't really get under all that good stuff, so if you cut it, just slightly, i can see, okay, that here is where it is going, and here is where it's coming from. i can always flap it back, and be like, right, that's where it's supposed to be. now that i've seen the orientation,i can flap this up, and you can really start to get into your organs and your small intestine and stuff.

okay, so now that we've clean up this area, we're going to start breaking into the chest cavity. again, we're avoiding this area here until week two, when we get into the circulatory system. but this area down here, this is where our lungs and our heart is. and that's what we do want to expose today. so, same kind of thing. i always want to start coming in on the sides, either over here...or over here, on one of the sides. because the only thing you're going to hit on these sides, are the lungs.

the lungs are very big, and they're very obvious. so if we nick one of the lungs, that's going to be okay. so i'm peeling over here, and i'm kinda cutting through the ribs, and just like...just like we did with the body cavity, if i were to cut through here, which you can see, is it opens up into it's own little cavity. so if i were to cut these ribs away...

you can see that this kind of opens up. you see we nicked a lung, but that's okay. you can get right into there. so once we can see it, then we know we're not going to hurt anything. so once you open up that little pocket, then you can start cutting a little bit more vigorously, because you are not going to hurt anything, because you can watch what you are cutting. if you'd like to go layer-by-layer,

that's fine as well. you can basically just remove these layers of skin here. and what you see, is you see all the muscles... and then you'll clear away the ribs. and you can do that too, that's fine. it does take a little bit longer though. but if you're worried about cutting something, you're nervous...that's okay.

remember, this is three-hour, study-at-your-own-pace labs. go as slow as you'd like. just make sure that you see everything, before the last day, week 3. okay. now we've exposed... we've got our lungs here, this is a little lung there, and this is a little lung right here. this is just some more ribs. you can see where the diaphragm ends here.

so that's gonna flap down and cover the whole body cavity. and then in this chest cavity up here, got some more guck in here...all right, clear that out. and then that chest cavity here is separate. nice, open chest cavity. these little triangular things, these are our lungs, right here. and we've reached our heart. our heart is surrounded right now, by this little membrane, that i'm lifting up.

that little membrane is called the pericardium. pericardium..."peri" means around, "cardium" means heart...pericardium membrane that surrounds the heart. so that's an important one. this is where we want to start being really careful. because we don't want to cut into any of that circulatory system, and any of those veins and arteries that we want to look at later. alright, now i'm just removing this top layer of muscle and skin. and i'm being very careful not to cut the arteries and stuff underneath.

see how shallow they are. okay, be very....very careful in through here. okay, so we want to lift up these ribs, and you want to cut right underneath them. you can actually cut the ribs away without damaging the thymus or the pericardium. [silence] now, if at any point you do cut away something that is important, it is not the end of the world.

there are lots of resources and information online. this pig dissection is very, very common. so you can look at other websites. they've got practice tests. they've got examples. they've got lots and lots of things that you can only look at online. so if you do not understand here in class... maybe your pig didn't have a really good thymus. you can always google these things.

and google images of what these things are supposed to look like. and they will absolutely help you. your book is the best resource for that, because they have really, really good, clear pictures. now, not all the pigs are going to look similar. bobby's pig is going to look different than jenny's pig. so you need to know what the different pigs look like. so this is where we encourage the people to walk around the lab. especially if you have a female, you need to go look at what a male looks like.

when we get down to the reproductive system, you are responsible for both. it doesn't matter what sex of the pig you've got, you are always responsible for both. so now that we've removed all of these ribs here. we're gonna leave this central section alone. because, again, that's where all those veins and arteries and really important stuff is, and we don't want to cut those. again, this is another good time to use our pick.

so we're going to start picking away this membrane. picking away this membrane now. what you can see here, is this, this membrane, again this is our pericardium. this membrane is actually a very, very tough membrane. so we've already broken through it, which is nice. but otherwise if you have the pick, it might be easier just to snip

a little bit of this pericardium membrane off. what i'm going to do, is i'm going to cut it, but i'm going to leave it almost all in tact. i'm going to cut it in half, so i can flop it open or back, then i'm going to leave it in tact. because, depending on whether we are above or below the pericardium, will matter what organ we are talking about. and, again, you can always cut away,

any of these that are blocking you, so you can access everything. so now you have cut this membrane. so what i can do is i can lay it flat again. just like this. or, i can fold it back. so when i lay it flat, when i peel away these lungs, what you see on the top right here,

this little flap, this darker part, so this membrane is a little bit whitish. you can see here...mostly kind of grey. this 'glandy' guy, looking right here, this is our thymus. remember we had a little thymus up here. this is the thymus where we really test you guys on it. so this thymus here, is sitting on top of the pericardium, on top of the heart.

so this is where it's important to know, are we below or above the pericardium. because above the pericardium, like we are now, is this thymus. this whole thymus right here. if we were to move this pericardium back, and flap it like this, underneath this pericardium, let me just pull all this back. and cut a little bit of this.

...got some more guck. so, again, if at this point, you want to pour some water on this. to help alleviate the smell, or the, uh, gross squishies...that's okay. so what you can see here, now that we're under the pericardium, and we've pulled this back, this is an auricle. so there's one here. and then another one on this side of the heart as well, right here. and these are two flaps that sit under the pericardium, but on top of the heart.

so that's why you need to know, whether you're under the pericardium or on top of the pericardium. whether you're talking about the thymus, or whether you're talking about these auricles here. and these auricles are just part of the atrium. um, so you've got one on top of here, and you've got one on top of here for the heart. move this back... and that is the chest cavity. in the chest cavity, again, this is our heart, right here.

we've got our lungs, on either side, these big, triangular looking guys. surrounding the body cavity, which is this membrane here, this thick, musculature membrane that goes all the way around, that is your diaphragm. the giant blue-guy in our body is our liver. our liver. so it's got all these different lobes. but it's all the same consistency and roughly the same color. so this is our liver. so this whole thing is the liver.

remember we've got the umbilical vein, which is attached to our umbilical cord. if we lift up... if we lift up the liver very, very gently, and you always want to use some kind of tool. you never want to use your finger, because your finger can actually be very damaging. so if we're going to lift up, we're going to try not to pierce. we're going to hold this here. but if you lift up,

on the right hand side, you're going to see this little deflated sac here, under the liver. that little deflated sac is your gall bladder. so the liver produces bile. the gall bladder stores the bile. and, again, it comes out this tiny, little tube going towards the stomach, and that's your common bile duct. so that where it sends the bile. this big, deflated sac underneath the liver, has to be our stomach. it's usually right next to this little tongue-looking guy,

this little feather/tongue-looking thing, and that is our spleen. so that's always going to be on the left hand side. that's our spleen. and then if we kind of gently lift these up, what we've got underneath, is we've got this fatty, kind of, white, bulbousy material. that's right up in here. and this is one the lobes of our pancreas. so day one, your pancreas should look like this.

by day two and day three, it gets a little bit degraded so you want to make sure you get lots of pictures of the pancreas. and really make sure you know what it looks like, because that guy has a tendency to shrivel up and kinda be hard to see. so next is everybody's favorite part, the small intestines. so if you look on our sheet, small intestines is not one of your vocabulary words. so if you answer small intestines on the practical, you'll get it wrong.

because, what we want you to do is we actually want you to identify the different parts of the small intestine. and, there are basically...i don't know...five parts. so we're going to start over here at our stomach. remember this big sac-guy. and we're going to follow it down. so where the stomach starts going into the small intestine, you've got this kind of hard, bulbousy... uh...kind of colon-looking thing right here. and that's your duodenum. or, as people say, "duo-denum"

so this is your duodenum. and this is basically the first part of your small intestines. so it's very distinct. it's got this almost, hard part, right here. so this is a sac, deflated sac. this is hard. and this is where it first starts, is your duodenum. so your duodenum then, leads over here. and you've got all of this intestine-looking stuff. here.

and what you can see is it kind of separates up into three distinct areas. one is this spiral-looking colon thing, and that is just that, it's your spiral colon. and so you can see it's spiraled, and it looks just like a colon. so it makes sense to call that the spiraled colon. over here, we've got all of this connective tissue. so you can see when i lay it out just like this it's all of this connective tissue,

holding in these small intestines. and that's because this is the jejunum out here. and the jejunum is responsible for nutrient and water absorption. so this mesentery here, which is our connective tissue...all this mesentery, is actually aiding in absorption. so this is where our nutrients are coming to be absorbed. so then you follow it down, and down, and down, and still all of this mesentery...mesentery...mesentery

until finally you get to this area where there's very little mesentery. and in fact, it kind of falls off onto this little ball by itself. and this little ball by itself, is very little mesentery or connective tissue, is called the ileum. so, again, out here, all of this is jejunum. so if we were to pin this, it would be jejunum. if we were to pin this in here, that's mesentery, including our mesenteric arteries and veins.

and, then, over here it kind of falls off into it's own little ball. right there. and that's your ileum. so this whole area's ileum. and, again, that's still for absorption of nutrients and water. but it's not as much. so most of the absorption happens over here in the jejunum. now in between your ileum, and your spiral colon... because everything's connected,

so everything keeps flowing, and flowing and flowing. you're going to find a little dead end. here it is. and we've got this little dead end guy. where you can kind of see that, yes, he's attached, by a little connective tissue right there. but really he's, like, this dead-end-guy. so if i break that you can see that he just ends right here. and that's your caecum.

this is your caecum right here. so its this little dead end-guy. so, again, we've got jejunum, we've got ileum. we've got our caecum, our spiral colon, our mesentery. so that is all the small and large intestines this would be considered the large intestine, and this would all be considered our small intestine, right here.

alright! so then if you peel all this up. and we have a little water in here, so we'll just dump him out. i'm going to keep the legs nice and taught. if your pig comes undone, you can always just re-tighten. tighten, tighten, tighten. there we go! okay. so back here if we lift all this up, you can see this is our rectum right here. so this our rectum leading down from all the

large intestine, small intestine. this is where, um, non-digestible material is removed. and then it leads to the anus, which again, is where all of that is literally removed from the body. so if we move over here... basically what we have... if we kinda break some of this tissue up... and, again, this is what you probe is really good for. you can see these big, round, beam-looking guys on either side, right! those are your kidneys.

you've heard of kidney beans, well that's because they look like beans. now these giant guys right here, are your kidneys. and this is our pancreas. and if we kind of pick through this... connective tissue... what we're going to get to is this very small gland sitting on top of the kidney. and that's going to be our adrenal gland. so "a" or "ad" means 'on top'.

and "renal" means 'kidney'. so the adrenal gland sits on top of the kidney. now, for whatever reason, i always find that one side has a better one than the other. typically i find it's on this side. if you can't find it on this side, you might want to go to the other side. so what we've got... because i'm pulling this away, this should actually be all connected.

so actually our adrenal gland is this little white flap right here. this tiny, little flap. and see i've kind of broken it a little bit, right there. which is why you always want to get very slow. so this guy, would be... if he's sitting like this... like, if i stop pulling him apart, he would be sitting right on top the inside, upper of the kidney.

so the adrenal gland is always going to be right here. so this little, white flap, right there, actually sits right here. and that's your adrenal gland. ummm, and i think, again, we've got the umbilical arteries here. this is our urinary bladder. and i think that's it....the body cavity! okay so basically what we have here, is kind of the map of our

intestines and basically what's going on in our body cavity. so if you can think of it like that, you can basically trace your way around, and it will kind of give you a better idea of where everything is and what everything is next to. so in case you don't even know what it is, on the test, at least you can deduce a little bit and kind of knock out the ones that you know for sure that it's not. so, we're going to start at the top, this is the liver, so we're basically right here in the body cavity. if we were to lift this lobe up, on the right hand side,

we're gonna have the gall bladder. this little deflated sac underneath the liver. it's going to feed down into this common bile duct, here, which enters into the stomach, basically this deflated sac underneath the liver is the stomach. if you were to lift that up, you see all this fatty, glandy...it's usually white or gray, that's your pancreas. it goes on both sides, it's got two lobes. on the left hand side,

always, if we're looking at it like this, we're always on the left hand side, this is going to be our spleen. it's that red, tongue-looking thing that comes out. and then coming off the stomach, the first part of the small intestine, coming over to the right, is going to be the duodenum. so coming off the stomach, this first part is the duodenum. and then you're going to come down into all this, what looks like small intestine stuff. and this out here is, if you were to spread this out, it's got all this connective tissue.

this connective tissue is known as mesentery. and then out here are the actual intestine itself, is known as jejunum. and jejunum uses mesentery to absorb things, which is why all this mesentery is here. so if you were to follow this down and around, what you basically come to again, is this small intestine looking thing but it kind of balls up into this little ball all by itself.

it's got a little mesentery, but not a lot of mesentery. and this right here is what's known as the ileum. so this little ball of small intestine that kind of falls off by itself, is the ileum. separate from the jejunum, but the same type of material. now, this spiral-looking, colon thing, right in the middle, is going to be your spiral colon. makes a lot of sense.

this is also considered the large intestine in these guys. don't write "large intestine" or "small intestine", because that's not on your test. remember only write what's on this sheet which is "ileum", "jejunum", etc. so in between the spiral colon, in the ileum, is a kind of, little dead-end. where all this connects and continues, and connects and continues,

there's a little dead-end section. and this little dead-end section, right here, is known as the cecum. so the cecum, in humans, it would actually have the appendix off of it, but in these pigs, it's just this little, kind of dead-end, and that's what's known as the cecum. it can be kind of hard to find. if you look between the spiral colon and the ileum, it's usually right there. now, on either side,

we've got our bean-looking things, these are our kidneys. sitting on top, on the inside of the kidneys, is this tiny, little flap, known as the adrenal gland. remember "a" or "ad" means on top, and "renal" means kidney. on top of the kidney. um, coming in and out of the kidneys are these two veins and arteries. ...sorry, one vein and artery. you've got your renal vein and renal artery...depending on if they're pink or blue. and then just below them, this white, squiggly looking thing,

coming out and going down towards the urinary bladder, that is your ureter. that is your ureter, which comes out of the kidneys and goes to the urinary bladder. coming down from all of this intestine, is our rectum. so it basically, kinda looks like this colony-looking thing. which comes down the length of the body and then out towards the anus. [music]

okay guys, so now we're going to go a little bit into the circulatory system, so that you guys understand the pathway of blood through the heart, and that will help you identify some of these organs and these vessels. okay! so we're going to start over here. we've got our four chambers of the heart. you've got your atriums up here, and your ventricles down here. this is on your right hand side.

because, say we're the pig...so, again, this is our right hand side. so you're gonna start here, the vena cava. either the superior or inferior, also known as the cranial or caudal cranial, because it's above the heart towards the head. and caudal, because it's below, towards the tail, like a caudal fin on a fish. and so we're basically going to feed deoxygenated blood which has sucked all the oxygen out all through the organs

this has returned deoxygenated. into the right atrium, down the tricuspid valve, to the right ventricle, up and out the pulmonary valve, to the pulmonary artery, so think of this as kind of bypassing, or going behind, the pulmonary artery, remember this is the only artery in the body that carries deoxygenated blood.

so "artery's" definition means "away from the heart". so this is the pulmonary artery, because it is still an artery, it's going away from the heart. but this is the only one that actually carries deoxygenated blood, which is an important one. so then we're going to go to the lungs. in the lungs we're actually going to find these capillaries. these small capillaries. good? [off camera] yeah.

and basically what's gonna happen is these are very thin membranes, so the deoxygenated blood is going to flow in and as it flows over all these thin membrane gaps, this is where the oxygen is actually, um, absorbed into the blood. and that's where you get that transition from deoxygenated blood to oxygenated blood. so then we're going to return in the pulmonary vein. "vein" because it's going from the body to the heart. but it is oxygenated.

so this is the only vein that has oxygenated blood. which is also important. so then we're going to go into the left atrium, down the bicuspid valve, into the left ventricle, we're gonna go up and out the aortic valve, towards the aorta, where we said oxygenated blood all over the body. this first little branch, right here,

off the aortic arch that you can see, this little branch is known as the brachiocephalic trunk. or, brachiocephalic artery. so again this is that first branch off the aorta. okay guys, we're going to continue on to the rest of our circulatory system. so basically to let you know where we're at, we're basically right here in the throat, and we're gonna work our way down. so you've got the big ball in the throat, that's the larynx. feeds down into the bumpy-throat...

bumpy tube in your throat. that's the trachea. at the base of that, is the little bean-shaped guy, that's your thyroid gland. sitting right at the base of that. now on either sides of your throat, there's going to be three different vessels. one artery and two veins. and what you can see, is this is going to be this big red one, which is our artery...this is our carotid artery.

you kind of heard, you know, they cut the jugular, cut the carotid these are major arteries going up to your brain. so this red one is going to be your carotid artery. and then these two blue ones, on either side of your throat are going to be your jugular veins. so remember the red ones are the carotid, and the blue ones are the jugulars. now for the rest of this part here, we're going to be talking mostly about veins.

so when you cut to this inner section, it's really easy to think of this whole system as kind of confusing, but if you break it down it's actually quite simple. so we're going to call our jugular veins here...we're going to call that 'one'. so, again, we're not going to ask you the difference between internal / external. your ta's probably not going to ask you the difference between right and left because students get confused about whether it's your right or the pig's right.

just remember the order. so we've got jugular vein 'one'. the first branch off the jugular here, is our cephalic. remember, same on both sides. we're just talking about this side. so we've got, one: jugular, two: cephalic. 'three' is this second branch, here,

but only from here to here. once it branches again this is your subclavian...is 'three' but 'four' becomes your subscapular and 'five' becomes your axillary. so if you can count: one - jugular, two - cephalic three - subclavian, four - subscapular and five - axillary you guys will pretty much be good for all of these veins in this area right here.

now, remember this central inner section, right here, is actually your brachiocephalic vein. and the way you can think of that is think of 'branches of the cephalic' vein! you've got your cephalic right here. you've got all these branches. so this is the branch of the cephalic, right there.

your brachiocephalic vein. we're back in the mesentery. again, this is all our jejunum out here. this is our mesentery here. if you peel back some of this connective tissue, what you get is these arteries and these veins in the mesentery and these are your mesenteric arteries

and your mesenteric vein. makes a lot of sense, arteries and veins of the mesentery. so, likewise, with that thinking, we've got our kidneys. remember, kidney... 'renal' means kidney. so anything "adrenal" means on top of the kidney. renal veins and arteries,

are going to be the veins and arteries that are going in and out of the kidney. so this guy right here, should be blue but he's actually white, so this is gonna be your renal vein. and this guy right here, should be pink, and that's gonna be your renal artery. if they're not dyed too well in your pig on the day of the test, we'll make sure that it's very obvious

whether we're talking about the vein or the artery. you can see a little bit of pink here. that could be considered a renal artery. but again, day of the test, just remember renal means kidney. so the little veins and arteries coming in and out of the kidneys are going to be the renal veins and arteries depending on whether they're blue or pink. finishing up the last part of the circulatory system we come to the iliac and the femoral.

so, there's a lot of places that these arteries branch, but you have to make sure that you're looking at the right branch. so right around where the umbilical artery starts to kind of come up, see how it goes straight down and then this, basically, like, 90 degree turn, right about there is where you are going to find the iliac. so that's the first place you want to look.

it's a major branch off the aorta. so the aorta, just like the vena cava, runs the length of the body. so, yes, they're up here, but the are also running the length of the body. so when they're back here, they're going to branch. and this branch, right here, between here, and here. this is what's known as the iliac. right here. different than the ileum. this is the iliac.

and this is the iliac artery, right here. and that's gonna go from here to here. the iliac is gonna run down from the aorta, which is all behind here, which is behind the rectum. as soon as it branches, you can see right here, it branches, and splits into this, like, 'y' formation. this is where they become the femoral. so this is your femoral and your femoral, right here.

and, again, on these tests, you don't have to worry about the internal vs the external, left vs right...you don't ever have to worry about that. just know that before the branch is the iliac, and after the branches, are your femorals. okay, so this is a diagram from the biology 101 pig dissection manual, and this is on page 90, if you need a reference. but this is a really good cartoon diagram of the female reproductive system

so it really gives us a idea of what we are looking for, based on the differences. so, we're going to start at the top. we've got our vena cava. we've got our aorta. we've got our kidneys. which have got a little, tiny adrenal sitting on top of. just below that, leading out here, we've got our ureter. our ureter, again, filters down from the kidneys,

into the urinary bladder. this is our umbilical cord, up here, with our umbilical arteries and our umbilical vein. so, leading down here, on our aorta side, you can see this leads into our umbilical arteries and then right around where this connects, you've got your urethra, and your aorta's connecting to the umbilical arteries,

so you're gonna have the reproductive system. so then we've got our 'y' like structure here. so you can see on the very outside of the arms of the 'y' is our little...is our little bean-shaped, ovary guy. sitting right on top of that, is our oviduct. and then it leads down into the squiggly line, squiggly line, squiggly line, here, on either side. and those are the arms of the 'y'.

or what's known as the horns of the uterus. so these squiggles are all the horns of the uterus. where it connects and actually leads down to the body of the 'y', this is our body of the uterus, right here. so this is horns of the uterus, out here, and body of the uterus, right here. now if we were to follow that down, down, down, down, down, we actually reach the vagina, right here.

and this is our vagina, which leads out to our urogenital opening. surrounded by our genital papilla, which is this little structure, here. and what's really important to notice, is this kind of 180 degree flip. where you see off of the vagina, right here, is actually this little vessel known as the urethra, leading up to the urinary bladder.

and, again, this is where urine is transported from the bladder, out her urogenital opening. so this 180 degree flip, right here, is the urethra off of the vagina now if you guys study this picture, it will really give you good idea of where everything is and where everything is attached. so this is really, really useful in studying.

alright! so remember that we cut around the umbilical cord for the females. so she's got no reproductive organs down here. so what we want to do is we want to fold this urinary bladder, here. we want to fold that down. and, again, these are our umbilical arteries, because they're going up the umbilical cord. our umbilical vein was coming out of the liver and

going to the umbilical cord. that's your umbilical vein. and at the base of that, if you were to follow this all the way down, what's you're going to see is you're going to see this nice, squiggly line, right here. and this squiggly line, is this is the horn of the uterus. so this whole thing right here, is the horns of the uterus.

and you have to think of the uterus as a 'y'. this is the horns of the uterus squiggly, squiggly lines. at each end, we've got this tiny, little ovary. kinda looks like a little, tiny bean. lots of things in the body look like beans, but this is the smallest. okay, sitting on top of that, this tiny, little,

tiny, little fleshy part, right here, sitting on top of the ovary, that's the oviduct. so the guy's sitting right on top of the ovary. and then we've got our horns of our uterus. and if we were to pull this down, this becomes our body of the uterus, right here. so this is like the base of the 'y', branch of the 'y', base of the 'y'. if we were to follow this down here and you would have to cut all through here.

basically what we're gonna find down here is the vagina. so all you have to do is follow it from the base of, or the body of the uterus follow it down, down, down to the vagina. and it ends, back here, in our urogenital opening. so we pull back the tail, and you can see our mammary...our, uh, genital papilla, right here.

and that hole is her urogenital opening which leads to the vagina. now, just like in males, there is a small, 90 degree bend that leads up to the urinary bladder. and that is what's known as the urethra. so if we kind of clear off this space, here,

what you find is there's going to be a small tube that heads up. and that's what we have right here. so this tube, going to the urinary bladder, from the uterus, and the vagina, is going to be our urethra. alright, so the male reproductive system

is a little bit more complex, and there's a couple more things going on, but it's the same general pattern. so, again, we start up here with the kidneys, we got our adrenal gland, our renal arteries and veins, going out of the kidney, going to the urinary bladder, is your ureters on either side. okay! basically following this down to the urinary bladder.

and the difference is is right around here where we would have our ovaries, and our urethra, is instead we have this uh, vas deferens. so, these branches of the 'y' here are our vas deferens. this body of the 'y'

which would be, in females, the body of the uterus. in males, is the seminal vesicles. so this branch of the body of the 'y' doesn't go all the way down, it stops right here. but you still got this body of the 'y' and these two branches going towards either side. so, again, this is your seminal vesicles. and then out here, these two branches,

are your vas deferens. you follow this down basically you're entering this scrotal sac, right here. and inside the scrotal sac if you were to follow this down this leads down into your testis, which would be the, uh, ovary in females, but is the testis in male. and this epididymis

is sitting on top just like the oviduct is sitting on top in the females. this epididymis is sitting on top surrounding this testis. now, this is inside the scrotal sac. and if your pig is well developed then it will be inside the scrotal sac. but, sometimes, because these are fetal pigs and have not developed sexually,

they will be up here. so they will be sitting in the same spots as the, um, uterus and the ovaries would be. so you need to be able to differentiate between a male pig and a female pig based on, not only the seminal vesicles, the vas deferens, which look different than the uterus

and the horns, and the body but whether or not the scrotal sacs are present. an easy way to tell on the test is we'll always make the genital papilla obvious. so if you're looking at it and you can't tell if they're undescended testes or ovaries if you just look towards this genital papilla if you don't see one... then you have to know it's a female

those must be ovaries. so. just like in the females, the males' urethra also does this 90 degree, or depending on how you're looking at it, 180 degree flip. so coming down from the urinary bladder we've got this urethra, right here, and then it's gonna 'fwoop' so this 90 degree turn, right here,

goes from the urethra to the penis. so the easiest way to do it is start at the urogenital opening which is found just below the umbilical cord. so there's going to be this space in between. you can actually break that membrane up and cut the space away because it's all just skin and muscle. and you can expose this tube, here and this tube here is going to be the penis.

and, so you can actually rub your fingers back and forth across it, and it'll feel like a small tube. and i know that sounds silly, but you guys are in college, you can handle this. it's just a little, tiny tube and so you can find it and then cut away all that excess skin and then you'll expose this penis here.

and, so this penis is then gonna come and then go into this 180 degree 'whoop' this flip, and as soon as it goes through that flip it becomes the urethra. right here. and that's leading back up so that is basically all the ones you need to know. there is a gland behind

the urethra right before it does that 180 degree 'fwoop' and that is your bulbourethral gland. a lot of people cut this away so it's not a big deal if you didn't find it, because it's gonna look a little... ...remember it's a gland, so it's gonna look kinda like a bean. but, a lot of people to cut that away, if you're looking for the penis and the urethra.

alright, we're gonna have to cut some skin around... alright, so we are carefully cutting into the male reproductive system. so what we have done is we have cut we've followed the urogenital opening, down, and we've found this nice tube; and this is our penis, right here. it's in a space separate from the

urinary bladder, which is important to know. and what we do is we follow it down, and this is our scrotum, again, here. and, what we've done is, this was actually tucked in here, and what you could actually do, is you could pull it, very gently, and this whole 'sock' will actually come out, here. so let's see if we can do that just as good on the other side.

so, we've got this, and then you just pull this guy. and, now, sorry guys... ...and he comes right out. so these would be our scrotum. or, "scrotal sacs". together they're a scrotum, individually they are "scrotal sacs". and, now what we'll have to do is we will actually have to

open this guy up, and find our testis. and so, again, an easy way of doing it is if you kind of feel around, you can almost feel around for the actual... testis...if they're well developed. this guy actually has a rather large scrotum so it should be pretty easy to find. and then we just want to carefully cut into the actual sac.

[clipping] we don't want to cut it in half. but we do want to get in there. [tools clanking] okay, so then what you should be able to see... you want to very careful opening these guys. it's nice when they're undescended because then you don't have to go into the trouble of actually opening these. but in this case, we do.

so...here we go! so, what we've got, ...right here... ...is this nice little ball. right there. and that nice little ball, that is your testis. so you can see it kind of looks like an ovary, but it's a little rounder. this flap surrounding

that is your epididymis. surrounding this guy, it's providing protection, towards him. and, we've got some more stuff in here but we don't really need to know any of that. we basically just need this guy, which is our testis. right there. and that's in our scrotal sac.

together this whole thing is the scrotum. again, this is the penis leading up to the urogenital opening. so, now it's time for cleanup! we're all done for the day, we need to package up our pig, and clean our tools. so the first thing that you want to do is you probably want to set aside your tools. so you can go clean them.

you want to make sure that you remove any kind of pins. if you were using any pins to hold the pig up, and, again, set those aside to be cleaned. now, remember, we've got our pig tied up, but we don't want to untie our pig. what we want to do, is we want to simply slide these off so we basically got our pig on a string. so that next week, we can just slide them back around.

now. what's important, what you want to do is you want to get some paper towels and, again, you want to get these damp, but not super wet. so what we're gonna do is put some water on them and then we're gonna squish them out. if you use too much water on these pigs they'll actually start deteriorating.

and they'll start..um... basically, melting away. so, some of your finer organs you might not be able to see for next week. so you want this damp but certainly not wet and dripping. so then what we're going to do is we're going to take some of this bioshield, which is this pink stuff. which should be sitting on your ta's desk, and you want to spray anything that's been exposed.

so any of these organs that are opened the cheek, that's been opened, the throat. you want to give a nice spray to all that. and then what you want to do is you want to take your your wet paper towels...or your damp paper towels and you want to start covering the inside of your pig. so we're going to stuff him a little bit here. get those organs covered.

anything that might dry up and start to to break away, we don't want that. so we're going to stuff him here, just like that. make sure he is nice and covered, anything we've opened is covered. so, then what i do is take a couple more paper towels and i kind of close him, like this,

and i wrap the strings around maybe once. and you don't have to tie him up super well because he's going in a bag already. but you want to keep him so that his organs are gonna stay nice and covered. so then i place him in some extra paper towels and wrap him up just like that. so you've got a nice little almost "pig-in-a-blanket".

so, what we're gonna do is we're going to set him aside for just a moment and we're gonna go and we're gonna get our bags. so, remember these are the bags that we used at the beginning of the class. they came with the tag and strings. well, we've already used our strings. so these should be already on your pig. remember, never throw the strings away, because you won't get any more.

and then what you are going to do is you're going to take your tag and you're going to write your name on it... the pig's name, the class, and the teacher's name. so what we've got here is that i've named my pig "babe" my students are "john and jane", "tuesday at 11" is the class time, and "stephanie" is the instructor. so, again, this is how your tag should look. so what you're going to do is place your little

package of pig into your bag all the way on the bottom like so. what i do is i kind of squish out the air, and then twist him. you can see a nice little pig package. there's not a lot of air in there. and then you want to take your name tag

and just twist it around. like so. so that we've got a nice little package of pig. so next thing we're going to do is in the back of the room there are going to be several drawers with several names on them. those names are ta names and the class time. so you're going to find your drawer

with your teacher's name on it and then you're going to place it in the drawer. just like so. so these pigs are going to sit here until next week. so then we've got our tray. and in the beginning we're gonna have lots of little pig bits on the tray. so what you want to do is you want to come over here to the "animal parts bin"

so this is bin #1. and you want to take off any of those pig bits. and those are big chunks that you can pick up with your bare hands. you want to make sure that you get all of those off your tray. so next thing that you want to do is you want to come over here to the "pig juice bin" and you want to dump out any excess juices into the pig juice bin. and, finally, what you want to do

for the tiny, tiny, little bits of pig that we can't get off with our hands, you want to get some wet paper towels and you want to scrape the bottom of your tray. so we're going to scrape this, nice and good so that all the little, tiny pig bits that are in the paper towel are actually going to go into this bin that says,

"paper towels with pig bits"! okay! so those are the three bins. after that, we've got our nice tray, we're gonna take it over to the sink one squirt of soap if fine. and then some water. basically this is just to get any of that kind of left over juice or the smell off. pig bits never go in the sink!

there is a grate at the bottom of this to collect any pig bits. now remember, cleanup points are important. so you want to make sure that this grate is completely empty and there's no pig bits that have got caught up in it. and your ta's going to be very particular about that. now, once we've got our nice soaped and rinsed and clean tray,

these actually get stacked down below nice and neat. so you want to make sure that these trays are always stacked in a fashion where they can breath. so the air can get through here. but you can see, this is my favorite way of stacking them, down here. which is basically stacking them 90 degrees from each other. and so this lets the air get into the tray

and dry out that wax. so you don't have that smelly, nasty pig smell. and trust me, if there are pig bits in the sink, they're gonna get stuck, and they're gonna start to really, really smell. so, no pig bits in the sink. no juice in the sink. make sure that your trays are nicely stacked so that nice air can get to them. with our tools, basically you're going to wash them the same way.

a little soap, a little water, and then you're going to dry them off. ...little soap... ...little water... [water splashing] these don't have to be dried super well. because, again, they're just going to be used for your pig dissection. so, a couple of paper towels. nice clean tools. once we are completely done with the cleanup,

because sometimes things get splattered, then you are free to take off your gloves in a safe fashion. and gloves and any other kind of other paper towels, that you've used, that don't have bits in it can just go into the regular garbage. okay guys, so you're all done with the pigs. you've got your pigs put away. you've got all your tools put away.

trays put away. the very, very last thing, if you've borrowed goggles from us they need to go into the "used goggle" bins. that is because, if somebody comes back and you've put this on the "new goggle" tray, then they're going to have their sweat all over your sweat and it's just going to be gross. so make sure, used goggles go into the "used goggle" bins for cleaning.

last, but very, very not least is wiping down the desks. so you want to make sure that all your stuff has been put off the desk. and you want to take this bleach that we will have provided for you in this little squeeze bottle. and you just basically want to coat your desks and there will be sponges provided with those bottles. and you want to make sure that you get a nice covering of the bleach.

and that's just basically to make ensure that no future students have to use this desk with nasty pig stuff all over them.