the human tongue is quite the amazing little organ with many talents and functions now some of these functions you may have already heard about but I would be willing to bet that some of the functions and even myths about the tongue might actually surprise you like is the tongue really involved with the immune system is it some super special strong muscle well we're going to answer those questions and more by utilizing the cadavers in the lab to take a look at the inside of a real human tongue it's going to be a tasteful one so let's jump right into this anatomical awesomeness so let's start by taking a look at the inside of the tongue and we're going to use A sagittal head dissection so a cut through the midline and as you can see here is the amazing tongue now the tongue is an accessory digestive organ and food would eventually make it down here into the esophagus but as you can see the tongue is primarily made up of muscle tissue covered with mucous membrane and just think of the mucous membrane as what you would see as the surface of the tongue now these talents or functions of the tongue are essentially due to these two main components and what I mean by that is what can the muscle of the tongue do and what is the mucous membrane made up of which will contribute to its functionality so let's start by going into the muscle of the tongue and even talk about some of the myths surrounding these muscles that make up the tongue the tongue muscles can be broken down into two categories extrinsic tongue muscles and intrinsic tongue muscles the extrinsic tongue muscles actually originate outside of the tongue by actually attaching to Bone like you can see right here and then sending those fibers or inserting those fibers into the canal connective tissues of the actual tongue the intrinsic tongue muscles are a little bit different they stay completely within the tongue and we'll get to those in just a second but these extrinsic tongue muscles will help you to move the tongue in all sorts of different directions side to side in and out so that you can participate in all sorts of fun little activities like assisting with speech manipulating moving and shaping food licking things like ice cream cones and of course we can also throw in participating in tonsil hockey which an old school person like me that's what we used to call French kissing now there are four paired extrinsic tongue muscles one on each side for example we already took a look at this one here coming off the mandible or the chin bone and this is called the genio glasses genio refers to Chin glossus refers to the actual tongue now this muscle when it contracts will protrude the tongue or in other words help you to stick your tongue out but we always need to bring that tongue back in and we've got some other muscle fibers we can show you here so a few here from the hyalglossus muscle because it's coming off of the little high bone right there and this will bring the tongue back in or retract it the other two for you Anatomy nerds are called the palatal glasses in the styloglossus and I'll just include some information about those in the description below but what about rolling your tongue changing the size and shape of your tongue well that is done by the intrinsic tongue muscles now again those intrinsic tongue muscles originate and stay within the tongue they don't attach to any of the bones outside so pretty much make up the meat of the tongue now it might be kind of hard to decipher here there's actually four different paired intrinsic tongue muscles and they're named based upon the direction in which the muscle fibers go or what we would call fiber orientation there's this Superior inferior longitudinal fibers which goes the length of the tongue vertical fibers which go up and down in transverse fibers which come across because of those varying different fiber orientations it allows the tongue to change its shape in size and really gets involved with speaking and even swallowing and even things like say rolling your tongue so speaking of rolling your tongue we should probably address some of these myths regarding the tongue muscle now some of you like me may have heard when you were growing up that rolling the tongue was genetic well that doesn't actually appear to be the case now again you can't throw genetics completely out like they have zero influence but it's not like there's just this tongue Gene that says you can roll the tongue you can't they've actually done some studies where they've had people practice trying new tongue movements that they couldn't originally do and some people actually were to finally get the coordination to participate in some of those movements so if you feel like trying a new tongue movement get in front of a mirror do some practice and let us know how it goes and something else you may have heard is that the tongue is the strongest muscle in the human body well granted the tongue does participate in some pretty amazing movements due to those extrinsic muscles as well as the varying fibro orientations of the intrinsic tongue muscles and it is pretty active throughout the day with all the speaking swallowing and eating we do but the tongue is still not the strongest muscle in the human body it's muscle fibers are no more special than say like the fibers found on the triceps or the biceps and we are actually going to do a video on the strongest muscle in the human body so for fun if you already know what that muscle is or want to guess go ahead and put that in the comments below and we'll let you know if you're correct so next let's move on to the mucosal lining or the surface of the tongue now there are going to be some amazing functions that are associated with the surface of the tongue and obviously one of those is going to be taste and how it works but when it comes to tasting things I think it might be beneficial for your tongue if you consider tasting the sponsor of today's video 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box is super convenient with the multiple box options that I previously mentioned as well as that shipping directly to you did I mention that shipping was free because it is which is also an awesome benefit I also like the flexibility of choosing how frequently you receive the orders many people do it monthly like every four weeks but you could also choose to do it every six weeks or even every two weeks if you like to get your meat more often than that and you can also cancel at any time so if you're interested in filling up your stomach from the pyloric sphincter all the way up to the lower esophageal sphincter with high quality meat go to bchrbox.com human anatomy and new members will receive a 10 to 14 pound turkey free with their first box plus also get 10.00 off if you use the code 10 turkey we'll also include this information in the description below so let's really get into this mucosal lining or the surface of the tongue and the functionality that this provides now I promise we will get into taste but I do want to mention something that's awesome that I had no idea about until I took an anatomy and physiology class and that is that the tongue actually participates in some level of immunity you've heard of the tonsils right well there are actually lingual tonsils on the back of the tongue here let me just Orient you we're not talking about these structures here we'll get to those in a minute but this tissue back here that I'm touching with the probe is the lingual tonsil there would be one on the right side as well you can definitely see it looks different from the typical surface of the tongue that we're used to seeing here now most of the time when we think of tonsils we think of the Palatine tonsils that most often get removed in this particular section actually has and removed sometimes people even remove the adenoid or the pharyngeal tonsil but like those other tonsils the lingual tonsils are these amazing pieces of lymphatic tissue that help filter pathogens like viruses and bacteria and kind of help provide this first line of defense of any of those pathogens entering through the mouth another important function is this overall idea about sensation yes taste is a very specific sensation but right now I'm talking about things like touch you knowing that your tongue is being touched detecting different textures on Foods pressure detecting temperature even pain all of this is very useful information especially when we are putting things in our oral cavities or our mouths so that we can get information to know what to do with it swallow it spit it out kiss it back we need to know adding another function to the list is that the mucosal lining or that surface of the tongue has glands or lingual glands on top of it and those glands will secrete mucus as well as lingual lipase lipase is an enzyme that can help start breaking down and digesting fats so it kind of helps get the process started before that food gets swallowed down into the stomach so let's bring this all together by going into a little bit more detail of what the surface of the tongue actually looks like up to this point I've mostly just been calling it mucous membrane surface of the tongue but if we were to look more closely at the surface of the tongue we would see that it is lined with all of these different projections called papillae and there are three different types of papillae that we're going to talk about the filliform papillae the fungiform and the phallate the phallate and the fungiform papillae have to do with taste because they're going to have taste buds but the filliform papillae they do have sensation but don't have anything to do with the specific sensation of taste but they also do something super cool they increase the friction between say like your tongue and food that you're trying to manipulate so in other words it helps increase the grip so that you can more effectively move and manipulate the food in your mouth now there are some other animals that have quite the filliform papillae for example your cat has very pronounced filliform papillae and oriented in a very specific way so that they can participate in all the activities that they need to with their tongue now like I said the fungiform and the valet papillae are the ones that are associated with taste or in other words contain taste buds the fungiform papillae are these mushroom-like elevations that are scattered between those numerous filiform papillae now most of those fungic form papillae will contain taste buds and when they do they contain about five now to the naked eye these appear as these bright red dots on the surface of the tongue and that's because they have a high concentration of these tiny little blood vessels called Kepler's now the valet papillae are very easy to see especially on this cadaver dissection easy to see that is if you stick your tongue out kind of far because there's about 12 of these and they form this inverted V if we had the other side you could see that but you can see these phthalate papillae and these are larger and they will always contain taste buds they can contain anywhere from 100 to 300 taste buds and so some interesting factoids about taste that we should mention is taste this probably won't surprise people tends to diminish or get worse as we age and the tongue is not the only place where we have taste buds or taste receptors there's actually some taste receptors in the soft palate or the roof of the mouth back here even in the throat or the pharynx and also on this little flappy doodad because that's a technical term called the epiglottis and finally let's cover the last myth The Taste map or the tongue map and maybe like me when you're in elementary school you were handed this picture of the tongue where it was sectioned off into specific taste modalities like this area of the tongue was only for sour this area of the tongue was only for sweet sour over here bitter over here Umami over here those were the only areas where you could taste those different types of taste modalities well that's not exactly how this works the different taste buds or the taste receptors that sense those different taste modalities salty Bittersweet are more evenly distributed throughout the surface of the tongue yes you might have someone who has a might have a few extra receptors in this area for salty or sweet but it's not like that sectioned tongue map where you only get salty here only gets sweet over here again more evenly distributed thanks for watching everyone hopefully I learned something new and amazing about the tongue and if you feel like stimulating those taste buds go ahead and check out butcherbox that info is in the description below I also want to take a second to say thank you to those who donate their bodies to science we could not teach anatomy in the same way without their Priceless Anatomical Gift we also want to hear from you guys so please go to the comment section 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