VideoPoints

• ••• • •• • ••••• • •
BIOL 2301 Human Anatomy & Physiology I - BIOL2301_lecture23_1116
Help Tour
© Distribution of this video is restricted by its owner
Transcript ×
Auto highlight
Font-size
00:00 All right morning y'all, let's see we can get that mic working a
00:06 bit better. There we go. right. Um So today what we're
00:09 is we're going to be continuing on the ear. Um And then we're
00:13 move into the um the mouth and the nose. So we're gonna be
00:18 at three different forms of, of senses. All right now really,
00:23 two different forms. So we were about the ear and hearing and what
00:27 of uh things were we detecting? , what was it that we were
00:33 ? Say again, don't be So I'm so scared to mention something
00:39 class. Don't be scared. Good vibration is movement, right?
00:46 remember when we're talking about the that was a good answer. See
00:49 why you should be scared, This is you go on the examiner
00:52 I don't think I know stuff, know, just answer. All
00:55 So look, uh when we're talking the ear, we're talking about detection
00:59 vibration. So we're looking at sound hitting the tympanic membrane which is transferred
01:04 the oval window which is transferred to paraly which is transferred to the uh
01:08 limb, which is the detected by hair cells as, as that indolent
01:14 . So it's a form of mechanic . All right. And that's not
01:18 intuitive to think. Oh, I'm detecting the satellites but no,
01:21 actually detecting movement in a very specific and it's transferring information that movement into
01:30 the idea of sound. Right. other words, brain is ultimately detecting
01:36 that movement. So, equilibrium is much the same way we're gonna use
01:40 same type of cells. And what gonna do is we're gonna ask the
01:43 is what is my head doing? right. So I have three things
01:49 here. You see the thing up top? You ever done that dungeon
01:53 ? Yay dungeon drop. Who hates dungeon drop? I hate the dungeon
01:56 . I'm scared to death of Fell off a cliff, 200
02:00 Face plant broke my wrist. So have a good reason not to like
02:04 . But even before then I did like heights. It's actually my dad
02:07 like heights. My grandfather didn't like . It's an epigenetic thing. If
02:11 don't know about epigenetics, that's All right. So dungeon drop,
02:17 ? I like the middle thing a that's driving fast. I'm not talking
02:21 the girl. OK. I could the girl but my wife would get
02:26 little upset. All right. So , so driving fast. So,
02:30 I'm doing here is I'm accelerating and quickly in the car. And if
02:34 ever been in front of me or me, you'd know how much I
02:36 to drive fast. All right. one, this is one that you
02:40 may or may not have done If you've been to the,
02:43 science museum or if you've been over chemo boardwalk or if you've ever been
02:46 a fun place during spring break, see these all over the place.
02:49 is the human gyroscope. What they is they strap you in to the
02:53 . It has three rings, the rings work or uh move in three
02:58 planes. And what these three things representing here are the different kinds of
03:03 your brain detects or your, your apparatus detects. All right. So
03:09 top one represents vertical movement you can up and down. So that's,
03:15 simple. If you can't, if don't like those and never been in
03:17 dungeon drop type thing, think of elevator, you're going straight up and
03:21 . All right. The middle one fast, it's moving in the horizontal
03:25 and the last one is angular In other words, you can move
03:29 any direction, your head is just of detecting that kind of movement.
03:34 so the vestigial apparatus has two different of structures that we're interested in.
03:39 right. And we mentioned them when had the picture and I think in
03:41 next slide, we'll have the picture . We said we had the snail
03:45 that was the cochlear that was for . And then we said everything else
03:48 wasn't the snail shell is for detecting . So the region, so the
03:56 that contains in it, the utricle the saccule, the utricle and the
04:00 deal with the horizontal and the vertical . All right, when we're talking
04:05 moving in an angle or angular this is where the semi circular canals
04:11 in. All right. And so truth is is we're going to describe
04:15 in those kinds of simple terms, all movement is detected using all three
04:20 all times. All right. Now me just give you the quick explanation
04:24 then you can just nod your head say, OK, I get
04:26 Do you guys remember Vector's way When did you guys learn Vector's?
04:30 ? If you watched the movie Despicable , you know who vector is?
04:34 right. So remember what was Vector's motto? I do crime with magnitude
04:41 direction. So strength in a particular . All right. So if I
04:46 a magnitude of zero, do I have a vector? Yes, I
04:52 . It's just zero, right? I may not be moving but I
04:58 a direction that would be or counted terms of uh magnitude of zero.
05:04 for example, if have a I have direction in one in one
05:10 . Right. That would be But I have a direction of zero
05:15 the other direction. The vertical. right, it's, it's there,
05:18 just zero. So we just ignore . All right. And so you're
05:23 in an airplane or taking off in airplane, you have, you can
05:26 the horizon, you can see the because I'm moving off at an
05:30 But when I'm horizontal or vertical, at 90 or zero. So you
05:34 of ignore the other one but it's . All right. So our
05:38 even though we might be moving in horizontal, all of these systems will
05:43 active. But for the purposes of exam to make our lives easy when
05:49 talk about the utricle and the saccule it's defining specifically the primary direction,
05:56 . It'll just make our lives much easier. All right. So
06:01 we're looking at here, we're going start with the uh semi circular canals
06:04 I'm gonna have to move back and because my little pump pointy thing,
06:09 battery died and I forgot to change before it came over. All
06:12 So with regard to the semicircular what we're looking at here are three
06:17 canals that are basically circular in not fully circular, but they're mostly
06:23 . And what they do is they're set at three different angles.
06:26 have one in this direction. One that direction and one in this
06:30 Now, if you know anything about dimensions, you have an X or
06:33 and a Z plane. And that's what we're doing. We're detecting in
06:38 three of those planes. And what looking at is we're looking at the
06:42 movement of the head. Now, example that the picture shows up here
06:46 saying no, when I do I am moving my head in that
06:52 plane, right? And I'm causing of fluid inside that structure and it's
07:00 movement of that fluid that I'm going be detecting. Now, how is
07:04 possible? Well, structurally at the of each of these. So I'm
07:09 go ahead and just circle stuff and at stuff like this at the base
07:14 your semicircular canals. So each one them has a structure called an ampulla
07:20 . When you see that term in just means a space that is
07:24 all right, it's amplifying getting So there's lots of ampules in the
07:29 . But in this particular case, ampulla is at the base of
07:32 the semicircular canal and inside that Amla a structure that is made up of
07:38 gelatinous goo that kind of sits up a speed bump, it's called the
07:43 . Now, I'm gonna just warn . Now, we're gonna have a
07:45 of words that it would love So it's Aula cupula, macula,
07:48 gonna keep popping up. So you make sure you know which one goes
07:51 which. So we have an ampulla inside that we have a cupula and
07:55 can see that being drawn here, cupula just sticks up and it kind
07:59 sits there and it's really gelatinous and , but it sits up in that
08:05 . So when you turn your the inertia of that fluid causes movement
08:11 that cupula, It causes it to one way or the other. And
08:15 inside the copula are the hair So when the copula moves, the
08:20 cells move, and so that's what detecting. We're detecting the movement of
08:24 copula as a function of the movement the uh fluid. And so you
08:29 one on each side of your heads those, those uh semi circular canals
08:34 faced in opposite directions. So you see like this at the end of
08:37 fingers are the ampulla, you can they're like this. So when I
08:40 my head, the hair cells are in opposite directions. So one side
08:45 my head is firing faster, the side of my head is firing
08:50 And those signals combined tell my head way my head is turned. All
08:56 . But that's really the idea. all I'm doing is I'm looking at
08:59 angular motion of the head. So I'm doing this, that's another semicircular
09:05 and put myself in that horrible nasty device and I spin myself in this
09:10 or when you guys were kids, you ever lay down on the merry
09:13 round head in the middle? Spin fast. Yeah. OK. I
09:19 one person nod their head. All . Right. It's the same
09:23 It's just how am I spinning. so this is how your brain knows
09:29 and how it understands that angular All right. So this is what
09:36 slide is just describing. It's just it. Very simply. Look,
09:39 turn my head cause the cupula to . When the cupula bends, the
09:44 cells, uh bend. And that is what's sending a signal through the
09:50 nerve up to the brain to tell what's going on. Now, I
09:57 like this picture here that they're but it's, it's an accurate
10:01 right? It says, look when nod my head up and down,
10:04 moving my head. I just Did anyone to hear that?
10:08 I'm just just making sure, you , if I'm doing this, I'm
10:12 in the horizontal plane, right? I'm moving in the vertical plane,
10:16 ? And I'm also doing angular which is why I don't like this
10:20 . All right. So this is I want you to think about the
10:23 drop and I want you to think speeding in a car because it keeps
10:26 simple if I'm being dropped from a , very uh, high height,
10:31 moving only in one direction. If I'm speeding in a car,
10:35 moving in one direction. So I that's the easier thing to think
10:39 All right. But it's true when nod my head, I'm gonna activate
10:43 of, uh, utricle and the , they're both gonna be playing a
10:47 . All right. So, what refer to when we're talking about the
10:51 apparatuses or the ones that are found the vestibule. So, not the
10:54 circular canals, but the ones that in the vestibule itself, these are
10:58 the otolith organs and they're called the organs because they have these little tiny
11:03 embedded in that gelatinous goo that's associated them. That gelatinous do is called
11:09 macula. All right. So the is like a cupula. It is
11:14 a cupula cupula. Remember is a bump that stood up and is in
11:17 way for fluid to go. The is like taking a uh nine by
11:22 tray of jello and then putting a bunch of fruit in it and then
11:26 it that. Now you have a tray that you can take to a
11:29 and that's how it kind of And you can see up there,
11:32 a gelatinous goo. You can see little tiny crystals, the otoliths that
11:35 in there and they're just calcium carbonate . They're just embedded in there.
11:39 what they do is they provide mass that gelatinous goo and then you have
11:45 hair cells sticking up in the So now when you move, uh
11:51 inertia is going to pull the, Odalis because they have mass, which
11:56 gonna pull the macula, which is to affect the hair cells and their
12:00 . Now again, you can think this if you get in a car
12:03 someone like me and we press on gas. What does it feel
12:07 Are you pressed back into your All right. That's the inertia.
12:12 . That's the idea is my body not want to start going 60 miles
12:16 hour. It wants to slowly move way up there. But because I'm
12:21 faster than my body is ready to , I get pushed backwards. That's
12:25 inert. Ok. And so it's same thing is as you begin to
12:30 that those Odalis are sitting there I'm not supposed to be moving,
12:34 here I am being pushed backwards. want to sit back and so I
12:37 but the macula stay or sorry, stay, but the macula goes.
12:41 so that's why it bends backwards. about when you slam on the
12:45 you know when you uh come up that light and it's yellow,
12:47 yellow. So you accelerate and then turns red just about before you go
12:51 . So you slam on your brakes you slide in. What do
12:53 do you feel yourself go forward? . And that's when the odor lists
12:56 going, I'm moving at 60 miles hour because that's how fast we're
13:00 Right. I slam on the So it's supposed to be stopping.
13:02 my odor lists keep going. That my macula forward and that's my perception
13:08 me moving forward is the idea ok, I'm, I'm coming to
13:11 stop. All right. So that's the odor lists do is they provide
13:16 mass to the macula. The macula what's moving kind of like the
13:21 it's not fluid. Now, it's weight and it's the hair cells inside
13:25 we're using to detect the hair cells associated with the vestibular nerve which send
13:31 information on up to the brain and just tells you your position of your
13:35 . So we have two of these . One sits like this, one
13:42 like this. The one that sits this has hair cells sticking up.
13:47 right. And so what I'm doing I'm bending the hair cells forward and
13:52 . And so giving the sense of acceleration and deceleration. All right.
14:00 structure is the utricle. OK. other sits up and down like,
14:08 that means the hair cells are gonna sitting in this direction, which means
14:14 bend up and down like so which me a sense of vertical acceleration and
14:21 . That's the saccule. OK. it's a little bit more complex than
14:26 . We're not gonna go into the complexity about how the hair cells face
14:30 so on and so forth because it's a little bit more complicated than
14:34 But if you can remember these the utricle is horizontal, sacal is
14:39 structurally, what we're doing in terms setting it up the Odalis embedded in
14:45 macula, the hair cells embedded in macula itself. And this is what
14:50 detecting when I hold my head up . What's gonna happen is I'm not
14:56 detect any sort of changes. All . So in other words, there's
14:59 movement of the macula in either the or the vertical direction. So I
15:04 detect any movement. So I don't that acceleration or deceleration. All
15:10 So if I'm going 100 miles an , me moving at 100 miles an
15:14 , like in a train or in car, I'm not feeling that
15:18 right? Because I no longer have inertia. Notice what I'm dealing
15:22 I'm not talking about velocity. I'm about acceleration, right? When I
15:30 my head forward, I can tell I bent my head forward.
15:33 Because both the utricle and the saccular being affected here, I've tilted my
15:38 . So the Odalis fall forward and with regard to the saccule, they're
15:43 a different direction slightly. And so that that movement that my head is
15:48 . So when I'm doing this, get my angular acceleration, but I'm
15:51 getting my utricle and my saccule but we're keeping it simple utricle acceleration
15:58 the horizontal plane, saccule acceleration in vertical plane. If you know that
16:03 good to go. Ok. Does make sense so far? It always
16:12 me when you guys are dead silent this point. Do we understand?
16:18 , great. So that allows us move into the fun stuff. Did
16:24 have breakfast this morning? I'm so . We're gonna talk about food.
16:31 right. It's this, this part the lecture is very dangerous for me
16:36 I get really excited and I go on tangents and I could probably miss
16:39 on stuff. I'm just warning you . So I'm gonna try to just
16:42 it straight and try not to follow rabbit trails that I can follow.
16:47 right. So what we're gonna do is we're shifting gears. So we
16:51 with uh uh electromagnetic radiation. That the eyes, we dealt with me
16:57 reception that was both hearing and And now we're moving into a different
17:02 which is chemoreception. All right. so both the gustatory and the olfactory
17:08 detect chemicals, right? So we're have chemo receptors with regard to
17:15 Olfaction simply is a sense of We use it to detect chemicals in
17:19 air to tell us about the environment us. And what does that
17:23 well, it doesn't mean just food food is helpful. Like when you
17:27 by a barbecue joint, I does that just not excite you?
17:30 that your brain just not wake up go? Hm. That smells really
17:34 . Even vegetarians? Go? That smells good. But I'm not
17:36 eat that. I know. That's . Have you noticed that people have
17:43 unique smell to them? Yeah. I'm just gonna tell you now,
17:48 , your sense of smell is a times greater than males. All
17:54 it is a fact of life. who have babies can detect the
17:59 the distinct smell of their own It's crazy. And when I say
18:05 you guys have a sense of smell great in the minute, this is
18:08 exaggerated. This has actually been studied it's a real simple test. All
18:12 do is you take a chemical, put it in a fluid and you
18:14 it out multiple times so that you , you know, like let's say
18:16 have mils, you take out a , put it into another nine
18:20 mix it up, take out and just work it down and guys can
18:24 down to a certain point and then that, it's like I can't smell
18:28 but women, I could smell I could smell this. I could
18:30 this six times six fold dilution. it's a million fold. It's
18:36 All right. We walk into the , my wife and I will walk
18:39 the house and she'll, you smell I'm like, no, don't
18:41 it's not even, don't even try I'm not gonna smell it. I
18:46 , you know, when, when got the milk carton, she's like
18:50 . This, does it smell Honey? I don't know. I
18:53 , it's, it's milk, it like milk. I don't know if
18:56 might be a molecule in there that's off. I don't know. All
19:00 . So we can use to identify , we can identify danger and of
19:03 , the danger there is the stinky . All right. Now, the
19:07 is, is as, as good our sense of smell is it's still
19:10 the best sense of smell. We this dogs smell far better than we
19:14 . There are some dogs that can cancer. I mean, that's
19:17 but it's true. You know, can actually use it to detect things
19:21 are off in the body. with regard to the olfactory system and
19:26 olfactory epithelium, it is specifically located the upper nasal cavity and we kind
19:32 brought this up when we talked about skull structure and the nasal cavity.
19:37 the place that we're looking you can over here is at the very,
19:42 there we go, very tip top your nose. Now, normally,
19:45 you breathe, your air sits down , right? It's just you bring
19:49 and it comes in and gets sucked your lungs and you breathe back
19:52 But when you smell something interesting, do you, do? You notice
19:57 you, you pull it up higher what you're doing is you're pulling it
20:00 near the olfactory epithelium so that you detect the odorants that you think you're
20:06 or you're trying to detect. You may even go, you
20:10 I don't know why we do but it's like you lift your head
20:12 to try to get the air to right place. Now, the thing
20:16 we're interested in here are three specific types. All right, there are
20:21 than this and it's far again, more complex. But we're gonna keep
20:24 simple. Again, the cells that most interested in are what are called
20:28 olfactory receptor cells. You'll see them in some places as or CS don't
20:32 that confuse you. These are the that actually detect the odors. This
20:36 why we are most interested in This is a type of neuron.
20:40 right. It's an a fern neuron then supporting them are the support
20:46 And then the things that make olfactory or receptor cells and the uh the
20:51 cells or the mucus producing cells are basal cells and these are just stem
20:56 . So these are cells that can and you can replace them. The
21:01 receptor cells, their sole job is detect odorants. The supporting cells produce
21:06 and help uh keep the environment Um And basically play a role in
21:12 . I have a hard time starting drink here uh that play a role
21:17 supporting the cells. In other providing nutrients and other materials to the
21:21 . All right. Now, there's things in the olfactory epithelium, there's
21:26 glands that aren't going to be represented and we're not gonna worry about.
21:30 , what we're doing when we're talking mucus is we're talking about creating a
21:33 thin protective layer of watery mucus that covers the surface of the epithelium.
21:40 what we're looking at here, this the olfactory receptor cell. If you
21:44 at it, it looks kind of a green onion. Well, let
21:47 show you, I see that look . Green onion has these weird stalks
21:54 the top, right? And then the bottom, you have a bulb
21:57 at the bottom of the bulb, have a bunch of little tiny
22:00 right? That look like a green ? I know I'm not the best
22:04 . But does that kind of look a green onion to you?
22:06 Ok. Well, notice what we here. We have our bulb at
22:10 bottom. We have a series of hairs and then we have this long
22:15 that goes up. Now, granted has lots of, of leaves.
22:19 you know, that's the idea here that it's his large stock. All
22:23 . And so what we're looking at , the olfactory hairs are the dendrites
22:27 the cell and they con, converge and they form a kind of
22:31 thick dendrite that goes up into that of that neuron. And then that
22:36 the opposite side is the axon that upwards through the crim plate and forms
22:41 connects to a structure called the olfactory . And it's actually specific structures in
22:46 olfactory bulb that we're gonna be dealing in just a moment. All
22:51 So, um actually, uh I point out. So I don't know
22:55 you can see there, there's what we're saying is that these nerves
22:59 of converge and that's what, what forms the olfactory nerves. So,
23:04 we said it was a plural kind looks like brushes on a toothbrush.
23:07 that's what we're looking at here. the place where the chemo receptors are
23:15 are down here, they're on those hairs. All right. So those
23:21 are the receiving end and they basically or cover the surface of the epithelium
23:27 they're protected by this layer of Now, each one of these cells
23:32 specifically to one discrete portion of an . All right, an odor is
23:39 up of multiple molecules. What we these molecules in an odor is an
23:46 . All right. So you have and then you have an odor.
23:49 when you smell something like strawberry, not smelling one molecule, you're smelling
23:55 different combinations of molecules in different And it's that collective concentration of these
24:02 that give rise to the overall So, we're interested in that
24:07 right? The one little molecule that up the part of the larger uh
24:12 of smell. All right. So happens? Well, you take a
24:20 bunch of the olfactory receptor cells. can see those neurons, they're converging
24:24 , forming the olfactory nerve and they into this olfactory bulb. The thing
24:29 looks like the head of a All right. So all the little
24:33 hairs, those are the nerves themselves then inside the olfactory bulb, what
24:38 have are we have these weird structures are basically balls of cells. All
24:43 . So they're called glomeruli because of shape. We don't have any
24:49 All right. So the idea here that they're not actual balls. What
24:52 is is you have a nerve that in and then there are other cells
24:57 there and then those cells have neurons they form other relationships. And then
25:02 you look at the whole structure, kind of a ball like shape and
25:05 are thousands of these in the olfactory . So if you can see here
25:10 the little cartoon, it's showing you of them. But you can imagine
25:13 like this and there's, they're all there like, so, so what
25:20 have is you have nerves coming in then what these are doing is they're
25:24 nerves onward towards the brain. All . So they're going on to the
25:30 cortex. These structures, these all right. So the round structure
25:37 cells inside them called tufted cells and cells. Our first order neuron then
25:44 the olfactory receptor cell. Our second neuron then are these tufted and mitral
25:49 and they're the ones that are sending information on up to the olfactory receptor
25:54 the olfactory cortex. Now, we're first project to the cortex in the
26:02 . That's where we detect the the itself. So when I smell an
26:06 , my brain is going oh this is present whatever that chemical happens to
26:11 . But we're also gonna send it to the hypothalamus and the amy
26:15 That's the limbic system. What is limbic system for emotion? Right.
26:20 if I smell something, it might me happy, it might make me
26:22 , it might make me grumpy whatever is. So like, for
26:25 if you smell the uh cologne or perfume of your significant other, you
26:31 that. What's that gonna make you happy, right? So that's what
26:35 limbic system is doing. And then also or it doesn't, this is
26:39 one place that doesn't project to the . All right. So it's kind
26:43 this weird one where it just bypasses . Now, I love this
26:51 Love both these pictures. So what you see up in the top job
26:58 ? Uh What do we have? have a bunch of ladies in lab
27:05 and what are they doing? And pits on what kind of
27:10 Fat men, not just men, fat men. And so what are
27:14 men doing during this period of Sitting in? What looks like basically
27:18 or towels maybe? What do you fat men? Do? They get
27:26 when Batman get sweaty? What do do? They stink? So what
27:31 you think these people are doing? testing deodorants. How do you know
27:39 a deodorant works just like you Yeah, it's working now. They're
27:47 to see whether or not this deodorant working and here's the best part who
27:52 doing the testing the women? Better sense of smell? That's exactly
27:59 I'm sure they make good money. I It's awesome. All right.
28:04 then on the bottom here we got scene from the Simpsons. This is
28:07 Mo opened up a family restaurant. kid says, hey, Mo,
28:10 drew a picture for you. I a picture of you, not picture
28:13 you, picture of you. And the picture he received Mr Stinky.
28:19 right. Now, I use this for a reason because what I'm trying
28:24 describe here is the characteristics of an . All right. First off,
28:28 said odors are not just a single , they are many, many
28:32 And so it's the combination of the that are detected that we call an
28:37 . So the individual molecule is what receptor cell is detecting. I think
28:41 reiterated that enough at this point. in order for you to be able
28:46 detect that odorant, that odorant has have a characteristic, first characteristic,
28:50 has to be volatile. Now, we hear the word volatile, we
28:53 explosive and that's not what it It means something that is easily
28:58 something that goes from a liquid state a gaseous state quickly. All
29:04 So if I took a drop or for a moment, right. So
29:08 in its liquid form and I put on this table, it would evaporate
29:12 quickly and it would disperse into the and eventually that odor would then permeate
29:18 from this point because it has vaporized the point where we actually put
29:24 Right. That's why why perfumes exist they do because they are already something
29:31 wants to go to a gaseous All right. The second thing that
29:36 to happen is that they need to , these odorants need to be sufficiently
29:39 soluble to penetrate through that very thin of mucus, to find their way
29:45 those olfactory hairs on the olfactory receptor . So, remember we've got these
29:50 tiny hairs and they're protected by a of mucus, right? So mucus
29:54 water plus a couple of proteins called . And so if I can move
29:59 that water, I can find my to one of those receptor cells and
30:04 detected. So those are the +22 for a deodorant, right? So
30:10 example, there are molecules in this , but I can't smell those
30:14 Why? What do they lack? not evaporating? Are they? It's
30:20 nice solid piece of wood. So molecules aren't escaping and finding their way
30:26 through the mins, right? But perfumes and your colognes and all those
30:31 , even though you put them on surface, they've already evaporated away and
30:34 why we can smell them. All . Yeah, we've already talked about
30:43 deep breathing. So what we're gonna is we're gonna inhale the air,
30:46 down low. It's not gonna come way instead it comes up and
30:52 And what we're doing is we're passing air along those turbinates. Remember we
30:57 about the nasal concha, right? sit in the nose and what they
31:00 is they take air which is moving a laminate fashion. In other
31:05 in a straight line. And what doing is we're crossing it over these
31:08 uh turbines and that what happens is create turbulence. And so what that's
31:13 do is it's gonna expose more air the olfactory epithelium when we breathe in
31:18 and uh in deeply, that air gonna in and it starts roiling over
31:24 . All right, bending and So this is why we breathe upward
31:29 why we have these structures and then odorants themselves are going to dissolve through
31:35 mucus. And then there's gonna be couple of proteins that sit in the
31:39 . These, this is the one the things I found fascinating. I
31:42 understand how this works. I've never it that deeply, but there are
31:47 odorant binding proteins and what an odorant proteins, it detects molecules in the
31:53 or recognizes these molecules in, in mucus detects them and then drags them
31:59 the olfactory receptor cells. It says is where you're supposed to go and
32:03 hands it off and it releases it it goes and looks for another
32:07 All right. Now, think about fast that's going on because when I
32:11 smell stuff pretty quick, right? these odorants are being picked up and
32:18 to the olfactory receptor cells. So happens when it binds to a
32:31 Well, again, or a receptor on the receptor cell, we have
32:36 signaling cascade. Does this look different anything we've learned about? So
32:41 we have a G protein coupled we have a G protein, we
32:46 an enzyme and then we have a that's gonna be activated by the
32:51 I'm not gonna make you memorize it you already know it. All
32:55 they just have their special name. the G uh protein is called
33:01 golf. Why? Because it's a olfactory and this is why we have
33:08 many of these is because in the cavity, in the olfactory epithelium,
33:13 have between four and 5000 different G coupled receptors to detect different molecules.
33:24 right. A dog, for has 40,000 of them. All
33:30 So that's why they have a broader . And so what we're doing is
33:34 have a very specific receptor that detects very specific molecule that activates a pathway
33:40 so and each cell is going to to its specific odorant and activate this
33:48 . When you activate the pathway, open up the channel. When you
33:51 up the channel, sodium and calcium into the cell. When sodium and
33:55 come into the cell, what are doing to the cell depolarizing it?
34:00 so that activates the cell to hey, I've detected this chemical and
34:06 your brain says, oh OK. it sends that signal up to the
34:11 cortex and in the olfactory cortex, says, oh when this signal comes
34:16 this point, this is the type smell that I'm getting. Now.
34:20 you ever smelled something you've never smelled ? Like you come across? I
34:25 know what that is right. And you learn what it is. And
34:28 the next time you smell that, know, then you can now recognize
34:32 . That's, that's the smell That's the olfactory memory, right?
34:37 let's say you're driving down in, , in Pasadena and you're, for
34:42 first time, you've never been down Pasadena, but you're driving by all
34:45 natural gas plants and you smell things , what do I smell? It
34:50 like rotten eggs and you're smelling the , right? So what are you
34:56 ? You're now connecting dots. You're your olfactory memory by associating the same
35:02 of chemical smells, right? The types of chemicals and you're associating with
35:07 things. So the next time you something like a rotten egg, you're
35:09 , oh yeah, that's kind of sulfur free, right? That's what
35:12 doing. So, in essence, time you smell something you are creating
35:19 unique combination of receptors that are being at different degrees of activation and it's
35:27 combination that your brain now associates with new smell. Another way to represent
35:34 is something like this. All Now, this is not something you
35:38 to memorize. I'm just trying to of like why? Like if you
35:42 strawberry and then that's like strawberry lip . Do they put in strawberry lip
35:47 ? What do you think? it's a different or unique combination of
35:52 they pulled out of the lab and unique chemicals smell like straw,
36:00 So are the same types of odorants are found in just strawberry and it's
36:07 enough. So your brain goes, , this is like strawberry and this
36:11 why it happens. All right. we're using a real simple model
36:15 You can say like, let's say have five odorants or five different uh
36:20 receptors. We have what is that different odorants? And what this little
36:24 is trying to show you is look that red seor, it detects
36:29 of the seven different odorants, but detects them at different strengths. So
36:35 when A binds to red, it's , really activated. But when D
36:39 to red, it's not activated that . Do you see that? And
36:44 if you look at, I uh the blue one, it's,
36:47 detects four different ones, whereas the one only detects one, but it
36:50 it really well or gets activated really . So you can imagine with this
36:56 because it's not just binary, it's on and off. It's actually different
37:00 of activation. Just with those, have almost an infinite combination of ability
37:08 detect stuff, right? And that's of what why you're able to detect
37:13 many different things is because all the of all the molecules that we can
37:19 is pretty much everything. All That's the idea. All right.
37:26 each odor is com is basically a of different odorants and we have these
37:32 receptors. And so you can imagine activating which receptors at which time and
37:38 much gives rise to that specific Right? That's the idea that this
37:44 trying to get to. Um we've about the sense of touch, sense
37:52 touch. We had a homunculus You remember that the, so we
37:56 it the somatotopic map. When we about the eye, we said it's
38:01 the light is hitting the retina. so in visual one, we had
38:04 retin topic map. Do you remember kind of is like where the light
38:10 the brain gets stimulated in a specific . So it's a retin topic
38:13 When we've talked about the ear in sense of sound, it's like the
38:16 . It's the mapped in the auditory just like the keyboard. Is it
38:23 or basically high notes to low So it's, it's tonotopic. All
38:28 . Well, here we have a an olfactory topic map. It basically
38:34 the same as your olfactory epithelium, olfactory cortex is mapped the same
38:38 So if you're detecting things in the , there's a specific location in the
38:42 that that goes to. If you're things in the back, it's gonna
38:46 a specific location as well and it's very similar. So it's kind of
38:51 somatotopic, but it's based on there, there's a chemical map that
38:57 maps to. Not. So but I thought it was just
39:01 All right. Now, we don't have 4000 receptors. We have hundreds
39:07 thousands of receptors, but we have 4000 to 5000 different kinds. And
39:12 one of the things that you can that you'll notice when it comes to
39:16 is that each of those glomeruli are to a specific olfactory receptor cell.
39:27 , if I have hundreds of thousands olfactory receptor cells, it means I
39:30 many of the same type of receptor , right? 100,000, I'm just
39:35 a simple math. 100,000 divided by is 25. You that should be
39:42 easy math, right? So just average, you can say there's something
39:46 25 receptor cells for each odorant. what that means is I may only
39:53 one or I can activate 10, ? Depending on how much of that
39:57 odorant is available, right? That may miss the one in the
40:00 but it can hit the one in back, that sort of thing.
40:03 those fibers are all going to the glomerulus for that particular smell. And
40:10 like in this particular example, we're gonna use red, uh
40:13 blue and green. You can think it as sour apple, blueberry and
40:18 . Does that work? Right? you can imagine all the sour apple
40:23 cells go to the sour apple all the blueberry uh uh olfactory receptor
40:29 go to the blueberry glomerulus and all cherry olfactory receptor cells go to the
40:35 glomerulus. And so that's how that is going to that very specific region
40:40 the olfactory cortex because you're actually presorting before it even goes up there.
40:47 is where we're gonna see lateral for example. So let's pretend that
40:52 have a really strong cherry smell. then within that uh one of those
40:57 receptor cells gets activated accidentally, maybe a blueberry molecule, right? Are
41:02 gonna detect the blueberry molecule? Probably the glomerulus probably gets activated but it's
41:08 repressed or suppressed by the cherry It says don't even worry about
41:13 What you're smelling is cherry. And it basically represses or suppresses the
41:18 So that blueberry brain only cherry goes to the brain. So the glomerulus
41:23 an important role of refining and processing by those secondary neurons that are located
41:31 . So you're actually pre um deciding you're actually uh recognizing. So kind
41:41 important. Finally, olfactory bulb moves the olfactory track. So that's just
41:52 arms of the toothbrush. So, if here's your head, that's the
41:57 , all right, going to the cortex specifically for that conscious perception of
42:04 helps you identify the smell limbic We've already mentioned visceral reactions. If
42:09 smell a stinky sock, right? about it when your brother grabbed that
42:14 nasty rotten sock and he shoved in face. And what did you
42:17 Yeah. Right. It's a visceral , right? Hypothalamus, amygdala helps
42:28 recognize odors and gives you that odor . Right? You go home,
42:34 smell those brownies. What does it you feel like? Happy?
42:39 So, those are, the is olfaction pretty straightforward. Ok.
42:48 is, is not particularly difficult. , you know, just understanding
42:52 the complexity there, the purpose of glomeruli purpose of the Miral and tufted
42:58 . All right, for the last bit here. And I feel like
43:02 kind of running through it because I'm I'm gonna go off on these wild
43:05 . All right, I usually do because Gus Station, I love these
43:09 . I just go on the internet hamburger just looks like perfect. All
43:17 , what we're doing with the sense taste is we're detecting the presence of
43:21 in our oral cavity. All This allows us to understand what's in
43:26 food and to determine whether or not something we want to be consuming.
43:30 right. The thing is, is gustation is heavily dependent upon olfaction.
43:37 , I'm just gonna try to use as an example. Have you ever
43:40 sick? And someone like gives you that you really like? I
43:43 it's food that you actually enjoy and like it doesn't taste so good.
43:48 don't like this. I'm not Why? Because my dog have popped
43:52 and I can't smell it. And why is soup so good?
43:56 , one, it actually has a of good stuff in it. Chicken
44:00 for some reason is like the magic . There's something in chicken broth
44:04 that is just good for you. right. So if you're ever sick
44:08 broth, chicken and stars, chicken rice, chicken and noodles, whatever
44:12 you happy. But chicken soup, . But it also heats up and
44:18 break down the mucus. So then can smell the food and smelling food
44:23 us happy. All right. So factory helps gustation. All right.
44:32 , the gustatory system is dependent upon presence of these papillae in the oral
44:38 . And the papillae have within them that are called taste buds,
44:44 So the papillae is not the taste . It's a structure on which the
44:48 bud is found. All right, are basically four different types of papilla
44:52 your mouth. Three of them are . One is the most common and
44:56 has no taste buds associated with it all. All right. Um The
45:01 bud, I'm just going to use again. It looks like an
45:03 When we look at pictures here in a moment, you'll see what I'm
45:05 about. It's not a green it's just a regular onion. All
45:08 . So the gustatory cells are located the taste buds. So you can
45:13 of see a hierarchy here at Pilla uh on the surface or embedded in
45:18 Pilla are the taste buds, part the taste buds are or the taste
45:21 are made up of gustatory cells. it's the gustatory cell that is actually
45:25 the detecting here. So there are types we're gonna do this. I
45:31 them around this morning. I was at this and I'm like, why
45:33 I ever flip these? So yours like flips. So just make
45:37 you know, foliate, fill a just to make sure your pictures are
45:42 . I know yours are flipped. right. So foliate, um these
45:47 the uh ones that are found kind on the sides of your mouth.
45:51 right. Now, you can't go there and really kind of see
45:53 They're like over here on the They're really, really active when you're
45:57 child. They predict a lot of because of your carotid glands. And
46:02 any sort of thing that gets dissolved that saliva is easy to uh to
46:07 here and you can see what it of look like. It's this big
46:10 and then those little gray things on side, those would be where the
46:13 buds are located. So you kind had this environment that indents downward.
46:18 if you look on the side of tongue here that the artist has
46:21 it kind of looks like gills and I said, you can go try
46:24 look for these things. You're not see these slits on your sides of
46:28 tongue. It takes a little bit effort. They're really, really
46:31 All right. So right now, aren't particularly useful to you. You
46:35 use these as much as you did when you were like a little kid
46:39 think about what a little kid Does they do, they pick up
46:42 that they can get their hands on shove it in their mouth,
46:45 That's how they learn about their You know, whether it be keys
46:49 cat poop, they're gonna pick it and they're gonna shove it in their
46:53 . They're gonna learn very quickly. poop is not something you want to
46:56 . All right, the filiform is most common. Now, I would
47:00 you to go home or even take phone and take a picture of your
47:05 and look at your tongue, Like to go, ah, and
47:08 , and you'll see on the, your tongue is you have a whole
47:11 of rough bumps. These are the . All right. So the name
47:17 foliate. It's leaflike. Filiform is like these are the short and spiky
47:22 that cover everything. And so they up the majority of the surface of
47:25 tongue and the purpose of this is grip food, right? Think about
47:30 when a cat drinks milk. What they do? They stick their tongue
47:34 and it dips into the milk and that milk gets trapped between the filiform
47:40 allows them to bring milk in by . When you eat ice cream.
47:43 the same thing as a cat drinking . When you lick an ice cream
47:47 , you're scraping the surface with these papillae and you're pulling onto the surface
47:54 your tongue so that you can enjoy if it was smooth, like
47:58 Yeah, you might get a little of ice cream, but it's only
48:01 melted stuff right here. You can scrape when you are moving food around
48:07 mouth. This helps your tongue, the food. So that's the purpose
48:13 . They don't have any taste but they make up the majority of
48:16 surface of the anterior two thirds of tongue. That's the portion that you
48:20 see. The posterior one third. can't see the biggest group of taste
48:27 are located in the circum valet Now, you can't see these.
48:33 right. And even if you had friend, uh and you basically grabbed
48:37 their tongue and pulled it, you see them. They kind of sit
48:40 here. So you can think if tongue wraps around and connects like here
48:45 comes around this, sorry, it be helpful with my hands on this
48:48 . Your tongue comes like this basically bottom third is what you can't see
48:53 then the dividing line between that third and that front two thirds is
48:58 you're gonna see these circum valet. you can see on the tongue,
49:02 actually dissected the tongue out, basically at the bottom and pulled the tongue
49:06 you can see the little bumps that kind of this flying v between the
49:10 and the posterior. Do you see flying v? That's right there like
49:20 inc So there's your circum valley. there's about 12 of these and then
49:26 they do is they're fairly large and is where the majority of the taste
49:30 are actually going to be located. can see them again, they're on
49:33 side. Notice they're not on the just like we saw on the
49:37 they're on the sides. They're not the surface. C the last group
49:44 the fungi forms fungi mushroom. All . That's kind of where it names
49:48 they do look like a little tiny mushrooms. And again, you can
49:51 that picture of your tongue or go in the mirror and you can see
49:54 , they, they are on the of your tongue, but there's only
49:57 100 to 300 of these on the of your tongue and they're scattered all
50:01 the place. In the little You can see like the little tiny
50:05 bumps in the, on the You have those and that's, those
50:09 the fun of forms. So they're scattered over the, uh, the
50:13 two thirds, they have very few buds and notice where they're located out
50:20 on the top side. All Have you ever had that,
50:24 that papilla that sticks up on your ? It hurts. You know,
50:27 can kind of, you feel it the surface of it and you're
50:30 ow, ow. Have you ever that? Yeah, that's probably a
50:33 form. All right. So sub has happened to it. And so
50:40 why it's kind of sticking up. this structure or these three structures minus
50:47 uh fili forms are where the taste are actually located. So the sense
50:52 taste is all over the surface of tongue in different locations. All
50:59 Now, a taste bud is a thing that's embedded into the side or
51:04 the surface of those papillae. And you can see it kind of looks
51:08 that onion. All right, I'll go to the next slide. You
51:12 see it really looks like an onion all the cartoons. That's really kind
51:14 what it is. Now, these embedded in the surface of these
51:20 So that basically it, they're encased the papillae and what they have is
51:24 have a little tiny opening from where taste bud is where they push out
51:29 s their ap apical ends into the environment. So there's a very,
51:35 small hole we call that the taste . The uh the uh uh apical
51:41 we're gonna see have little tiny hairs them that increases their surface area.
51:45 this is where the detectors are, is where the receptors are located.
51:50 all these gustatory cells, the cells are gonna do the detecting are located
51:55 that taste bud. And again, very similar to the gustatory cells.
51:59 the ones who do the detecting. a basal cell or stem cell and
52:03 there's some support cells that are found as well. So it's very similar
52:07 style as you saw in the olfactory . The thing is, is that
52:14 mouth is a very, very rough to live. All right, think
52:18 all the horrible things you do to inside of your mouth. See the
52:21 there, you know, hot we eat things like Doritos or
52:26 you know, rough foods and stuff that. So we're just constantly abusing
52:31 , the surface of our mouth and designed to take it. But what
52:34 means is that these olfactory cells or olfactory, these gustatory cells are being
52:40 all the time and so they're actually and turned over at a pretty rapid
52:45 , roughly every 10 days. All , that's rough lifespan. You can
52:49 about this. Have you ever burned inside of your mouth? You
52:52 got yourself that nice little Starbucks took sip and it was at 100 and
52:55 degrees. Yeah. And everything tastes copper for a couple of days and
52:59 a couple of days it stops tasting copper. It starts tasting like real
53:04 again because those cells that you damaged have been replaced and they're being replaced
53:09 other cells that do the exact same they did. Ok. So this
53:14 a common normal turnover uh event. , very, very short lives.
53:24 , gustatory cell is a type of uh epithelium. All right. So
53:29 a specialized, that doesn't mean it's nerve. It means it comes from
53:32 nervous system, but it's not a in and of itself, they have
53:37 little dendritic ends, uh these micro they call those taste hairs just like
53:42 saw olfactory hairs, same sort of . This is where the receptors are
53:45 be located. They extend outward of pore. And so they're exposed to
53:50 salivary content. So they're exposed to watery mucus as well as the stuff
53:54 floating around in it. And what doing is they're looking for the molecules
53:59 the materials that are found in the . These are called the taste
54:03 So if we have odorants, we tastes and there are four basic types
54:07 cells that we're gonna have to deal . All right, type one cells
54:11 , very simple. They respond to . All right. So they're looking
54:17 the specific ions that you find in . We have the type twos.
54:22 are the complex ones, they cover gambit of things. They detect
54:27 the uh molecules that give the sense bitterness. They detect things that give
54:31 sense of savory and they detect those that give the sense of sweetness.
54:36 all g protein coupled receptors. So a unique class and there's multiple types
54:42 these, the type threes sour. right. And we'll look at
54:47 how it does this. And then type form four are the stem cells
54:51 give rise to the other three. right. So what do we do
55:00 we're talking about the gustatory pathway? , we have two nerves, cranial
55:04 number seven, which is the facial nerve number nine, which is the
55:09 glossal is tongue pharyngeal throat. the tongue and throat, right,
55:18 and throat nerve. So, what doing is we're gonna be detecting our
55:23 and we're gonna be sending signals through the facial or the Glossop fringe.
55:28 are gonna uh uh I I, pointing out here in that second
55:32 uh the vagus nerve is going to epiglottis and la pharynx. Um We
55:37 have taste receptors located through our We even have taste receptors in our
55:44 . All right. And they're looking the presence of specific molecules to help
55:48 in the process of digestion or with to like the, the esophagus,
55:53 be like, if something noxious is down your throat. Have you ever
55:57 something? Like you can feel it the way down here? Yeah.
56:01 probably what you're activating. It's basically you something bad is going down.
56:05 , stop doing that. All But anyway, so what we're gonna
56:09 is we're gonna go to the medulla the medulla to the thalamus. All
56:13 . And what we're gonna do is gonna send information to the hypothalamus.
56:18 the hypothalamus? It's gonna give us sense of dimension to the food that
56:23 eating. So I may have told story here. I know I've told
56:28 to my other class. Uh, gonna demonstrate how stupid of a man
56:31 can be. All right, because all have that genius every night.
56:36 , every Friday I meet, with the other instructional faculty and biology
56:40 we talk about, uh, you , um, really we talk about
56:44 courses and, you know, problems stuff and things and ideas and
56:49 And one of these days, one of these luncheons, Doctor Cheek
56:53 showed up late, she was very . Oh, I'm so sorry.
56:56 was over at the library and I watching a red tail hawk eating a
57:00 and I was like, you yeah, I mean, it's for
57:04 biologists were like, yeah, you've that. It's like, cool.
57:06 like sitting there ripping the thing And I said the dumbest thing I
57:09 could ever say to another biologist as biologist, you know, especially since
57:13 teach this course. I'm like, , I can never understand this is
57:16 I, I can never understand how these animals can eat raw, you
57:21 , uncooked, gross things. I mean, they're literally ripping out
57:24 muscles and the intestines and they're, know, just gobbling it all down
57:28 they're the happiest animals ever. Have you ever watched an,
57:32 an animal eat another animal? They're , awesome. Go to the zoo
57:36 them at feeding time wa watch how they get. You know, it's
57:39 the seals and the, you throwing the, the fish at
57:43 they're like, oh, swallow the thing. It's not, it's not
57:46 cut right and rolled in rice and or anything, you know. And
57:50 like, ii, I just don't it and she looks at me
57:53 I'm the dumbest person on the planet rightly so, and she's like,
57:57 they have the right receptors to te them that the things that they're eating
58:01 the materials that they want in order survive. And I'm like,
58:05 of course, I mean, I that, but again, I think
58:08 food in terms of dimension and flavorful how exciting it is. When I
58:14 in college, I dated a girl ate food only because it kept her
58:19 . Right. I mean, you , that person or are you that
58:22 ? It's like I, food doesn't me. I have to eat it
58:25 if I didn't, I would That, that was her, that
58:29 her thinking. And then she met and then she learned that food actually
58:32 good because, you know, if I have bad food I'm,
58:37 , life sucks. And that's the of that. So, food has
58:40 be good. All right. So dimension part here, that's the
58:45 And so your hypothalamus is telling you is good and we all have different
58:51 of good. How many of you like oysters? One person was raised
58:57 23 good. All right. I to school in New Orleans. This
59:00 the home of good food and I grew up in the middle of
59:04 desert. I hate seafood. I , seafood to me smells like nitrogen
59:09 rotting because getting seafood in the desert nothing but old gross fish.
59:16 So, even in the home of best seafood on the planet, I'm
59:20 , uh, uh, and they're like, you have to try
59:23 . I'm like living boogers. because they are living when you eat
59:29 , right? You swall. So just like that, that, that
59:33 and they're, you know. Oh, I did. You threw
59:40 ? Oh, see, I did . I was much, much
59:43 Yeah. See, I had lots lots of beer first and then I
59:46 that oyster and I doused it in . So you already, you already
59:50 about this, about me? I eat spicy beyond spicy. So it's
59:54 like, I'm just gonna make it like something I actually like put it
59:57 my mouth. It sat there. went away. Then I could start
60:01 oyster, which made it even worse it just took every fiber of my
60:05 to just go. But I got down and it stayed down and I
60:10 I could eat it and that was . That was the last oyster I
60:14 had. And it screamed all the down. Don't eat me. All
60:22 , behavioral aspects also are gonna be with regard to the Olympic System.
60:27 you ever eaten up some food? it's just like, have you ever
60:32 that or like my kids every time serve them anything remotely green? They're
60:38 , I'm not eating that and then like, that's a behavioral aspect.
60:45 son is the worst he did. refuse to eat onions. You do
60:48 everything in there is an onion, ? He doesn't know all the food
60:52 tastes good to him is oniony. . So that's, that's the idea
60:58 the limbic system, hypothalamus. All . So I'm gonna give you the
61:01 primary tastes. When I sat in seats, there were four primary tastes
61:05 the time you're up here, if doing what I'm doing, maybe in
61:08 couple of years, there'll be probably seven. There might even be
61:11 every time you turn around. They're , here's a new flavor, here's
61:14 new taste that our body can All right, but five is all
61:18 need right now. So first is . Salty, surprisingly is stimulated by
61:22 presence of chemical salts. Yeah. specifically what we're doing is when salt
61:30 in your mouth with anything with what it does is it dissolves immediately
61:34 and then it's that sodium and what does, it goes into those type
61:39 cells and causes that type one cell , to polarize. And so that's
61:42 detection of saltiness. And so just remind you what salty is there,
61:47 got some salty, you know, salt up there and there's some salty
61:50 . OK? So in terms of , what you think of sour
61:56 what's something that sour that you Sour candy? This is the best
62:02 here. Sour candy name a sour . Huh? Airhead Extremes.
62:08 Can you come up with another We're gonna see how many sour ones
62:11 see how much we like sour. we have Airhead Extremes. Sour Patch
62:16 . That's the easy one. Oh, yeah. Warheads. What
62:20 all these candies sour citric acid There's also another type of acid,
62:29 acid. All right. Think of sour foods like pickles. You ever
62:34 sour pickles. Right. Dill All right. Acetic acid.
62:40 notice what we have here. When talking about sour, we're talking about
62:44 foods. And what's happening is, or not acidic, acidic. Uh
62:49 brain was seeing acidic, um, foods that's basically acids. And when
62:53 acid gets in the water, what does is it dissociates, it releases
62:57 proton and then you have your negatively . So you have that proton in
63:02 base, right? And what's happening is that that proton is binding up
63:07 a receptor and it's detecting that receptor activated, it causes depolarization.
63:14 they've uh what we've done, I'm just go to the next slide.
63:18 you can see it. And this picture right here, what do
63:20 have is we have citrus to remind and then over here pickles. So
63:26 acetic acid. Um But what this just kind of showed you here with
63:30 is it's the hydrogen uh ion binding this channel, this receptor. And
63:36 it does is this receptor is actually potassium channel. And so potassium is
63:41 just moving out of the cell and a uh hyper polarization. And so
63:46 you stop that hyper polarization, you move towards depolarization. And that's what
63:51 detection is. I'm not gonna ask that I just wanted to kind of
63:55 um I've seen different receptors named in and the, the type of receptor
64:01 is not so important. But the here is I'm detecting the protons in
64:05 acidic solution in the acidic food. what, that's what gives me that
64:11 of sour. We have sweet What we're looking at is specific configurations
64:18 glucose. Now again, I know is not a biology class, it's
64:22 a chemistry class. So if you know what glucose looks like, that's
64:25 . But basically, it's a ring . Normally, it can be split
64:29 made into a longer six carbon But normally it's this kind of ring
64:33 . And what we have here is have a G protein coupled receptor that
64:37 recognizes that ring structure. When it bound, it activates a cascade of
64:42 that then tells you this sweet cell been activated. So to remind you
64:48 sweet is, I have a brownie there, right? And I have
64:54 fruit tart. OK. So that's sweet portion similar to the sweet is
65:01 umami. Now when I was in seat, I did not have
65:05 OK. Umami did not exist. was discovered a long time ago,
65:08 only recently has it been allowed into pantheon of tastes and probably had to
65:14 probably at the time it being discovered Japan. And this was like in
65:18 fifties and forties. And we can't those Japanese and yada, yada
65:22 So we've known about Umami for a time. We just didn't include
65:28 And so what does it do? sort of thing? G protein coupled
65:32 . It is looking at the presence amino acids. All right. And
65:38 the presence of glutamate. And so binds to our amino acids bind to
65:43 G protein co receptor and gives you sense of savory. I'm giving you
65:48 stake up there for the sense of . Ok. Amino acid steak should
65:54 pretty straightforward because it's all protein. right. So that's the type two
65:59 cell. So we did the we did the twos and the other
66:04 of two deals with bitter. we're gonna walk through this a little
66:08 slower. What do we have up the top left corner? Where does
66:13 come from? Cocoa? Which is , right? Which is, what
66:22 it come from a plant, a or mineral? Or it said
66:25 vegetable, plant and animal mineral? it comes from a plant good?
66:28 . Up there in the top, . What do we have? Brussels
66:33 ? Ok. Where did Brussels sprouts from the ninth plane of hell?
66:38 mean, they come from, they from plants, obviously, it's a
66:43 and then down here in the what do we have? Good?
66:47 guys can recognize it? All OK. What in beer? Apart
66:55 the, um, what I wanted to focus on here is the sharp
67:00 , the bitter flavor that comes from ? Where did that come from?
67:04 you guys know what beer is made ? That's the first question, you
67:06 what beer is made? Ingredients are in beer. Unless you drink that
67:12 stuff from Anheuser Busch. In which , they put 400 to 4000 different
67:17 in it. Don't drink that stuff for you. All right. Good
67:20 has four ingredients. First ingredients, simple water, second ingredient, some
67:30 of grain. So barley or All right. And then what,
67:38 do you think? Golly hops? . And then we have some sort
67:47 malt. OK. The malt is coming from the wheat. All
67:52 Or from the barley? All And then as, oh,
67:55 And yeast, that's what, really the malt is with the grain
67:58 so yeast, what's her? The make the alcohol, right? It
68:04 the alcohol. It takes the sugars the malt. The malt, it
68:08 , oh, sugars from the And it converts it into alcohol,
68:13 makes beer palatable. Because if you taste a beer, if you have
68:18 first time you ever had a if you've never had a beer,
68:21 OK. Wait till you're 21. the rule. Unless you go to
68:25 or Louisiana. All right. And we had that beer and the first
68:29 you're gonna have a beer for those you who had your first beer.
68:32 it like the sweetest most yummy thing ever had? No one's gonna admit
68:37 here. I'm, I'm, I'm not an arc, man.
68:41 was it like, uh, it gross? That's, that's, that's
68:47 . You can say it's gross. right. It's kind of bitter.
68:52 does the bitter come from? Did know? All right. It comes
68:59 the hops. What is hops anyone that? See, there's lots more
69:07 when you guys know stuff. All , hops is a flower. All
69:13 . It's grown on a vine. a very tall vine. Usually they're
69:17 30 ft tall. And what they is they grow them up there and
69:21 they go and collect the flowers and use that flower to add to the
69:28 to give it. It's kind of tangy taste, right? Um Hoppy
69:35 are things like pale ales, like India pale ale. If you've ever
69:39 an IP a like, oh it kind of makes you the bitterness
69:44 it. All right. Now, reason they add this is not just
69:48 make you go, it's actually a to the beer. It allows the
69:52 to, you know, ss sit for a longer period of time.
69:57 in fact, the reason India pale are so hoppy is because they would
70:02 them in England and they put them ships and those ships when we're not
70:07 like with an engine, they would to sail all the way around Africa
70:12 go to India to give them to soldiers that were living in India at
70:16 time. And so in order to that trip, they had to last
70:19 , in order to last long, need to have a preservative in
70:22 So the hops is the preservative. a bitterness. Now, I pointed
70:26 three different things here we have, is a flour. We have
70:34 which comes from a plant. It's from the seed of the plant,
70:40 ? And then we have Brussels sprouts are leaves to a type of
70:46 All right, this is actually the plant. It's a member of the
70:49 family. The brassicas are the uh that humans have domesticated to the point
70:55 most of our vegetables come from You want a list of the
71:00 the, the. So we got sprouts, cabbage, radish,
71:06 cauliflower. And uh most of the the greens like um mustard greens.
71:14 of those are the same plant mutated a particular appearance and improved over time
71:22 create that thing that you're looking So the broccoli is the flour.
71:29 Brussels sprout is the leaf and each those are unique and different in how
71:36 look, right? I mean, if you've ever seen a radish,
71:39 is a radish? It's basically right? So they tried to cross
71:44 try to get like, hey, save up space, we can grow
71:48 roots and give them cabbage heads. tried to cross them so that they
71:52 get the big head, the big head and the big radish root and
71:55 know what? They got? The radish head and the little cabbage
72:00 So it's not an easy thing. of these things come from plants.
72:07 so what are these plants trying to us? Do you think?
72:13 don't eat me? All right, you gave chocolate to a dog,
72:17 did it do to the dog kills ? All right. You've heard that
72:21 feed chocolate to dogs, please don't to your dogs. All right,
72:26 these things are saying is they're producing alkaloid, that alkaloid is there to
72:33 , please do not eat meat. that's what each of these things are
72:38 . See, even the Brussels what's the Brussels sprouts saying don't eat
72:42 ? I will poison you and you die, right? Even the
72:49 but some of these don't kill And it actually provides a certain degree
72:54 pleasantness. But for the most imagine, you know, 50,000,
72:59 , 500,000 years ago and you're a and you're going along and say,
73:03 , look these berries look good and took, took these berries and shoved
73:07 in your mouth and they're all What's that? A signal of poison
73:12 kill me? So, what do do? Let's spit it out before
73:15 gets into your system. That's the of these, we have about 50
73:20 100 different types of type two receptors detect different types of bitterness. Some
73:25 them we use to our advantage, others of them are there for the
73:28 of protecting us. All right. , this is just a picture showing
73:33 the type two cells. We're down the last two slides. All
73:37 or three slides. All right. Notice I put the b do not
73:41 anything. This is just kind of fun stuff. Um So we've known
73:44 uh different uh tastes for a long , but I show this to you
73:50 show you this came out of uh around 2012, I think um out
73:54 nature and what it was doing was the history of uh taste receptors because
73:58 had just discovered one, maybe it 2020 10. Um And basically
74:03 this is how recently they've actually discovered specific receptors they've identified and localized
74:09 right? So the furthest one the bitter receptors, those T two
74:14 receptors discovered in 2000 salty, we what salty is. We've always known
74:20 salty is, but in terms of receptor, no idea. It's the
74:23 receptor was discovered in 2010. It's . Second thing you don't need to
74:31 here. This is just information. There are lots of different types of
74:36 that are located in the mouth and of these are are going to provide
74:41 and other aspects to the food that eat. Right. So your
74:45 remember how I see the world is on the receptors that are being
74:50 And so there are other types of receptors and um gustatory receptors that are
74:56 in and around the oral and nasal . So for example, uh a
75:01 receptor uh that we know of is car four receptor that's located in the
75:06 that detects carbon dioxide. Probably the of which is to detect the presence
75:11 carbon dioxide in the food, which a sign that it's contaminated with active
75:16 . But think about, do you sodas? Yeah, the fizz inss
75:20 the soda that's activated receptors. So actually has can provide a pleasant
75:26 Do you guys like fatty foods like ? Yeah. All right, cheese
75:32 protein in it, but it's predominantly and it's that fattiness that kind of
75:36 our mouths. There's, there are receptors located in the, in the
75:41 , there's likely fatty receptors located in mouth. And so I wouldn't surprise
75:45 if that is also true. The little slide here, this I think
75:50 , is important and again, not the purposes of being on the
75:53 but you will hear people tell you lie and I mean, even uh
75:58 will do this, they'll say, , um you know, if you
76:02 at your tongue. There are specific in the mouth where you will detect
76:07 things like sweetness is in the front the tongue and uh sours over here
76:10 the side. That's what the thing that have crossed out. And this
76:14 all based on the original study of mouth, which was done in 1901
76:18 this German Hannig who published this paper Germany in German about the structures of
76:25 mouth. And he basically said these the locations of where the receptors
76:29 All right. And so notice where he said the receptors are
76:32 said up here on the anterior surface here on the sides and way back
76:36 in the back which corresponds to the valet the foliate and the fungi
76:41 right? But when that paper was translated, it was misinterpreted as me
76:48 the the different areas that he identified specific to very specific types of
76:56 But we already know each taste bud all those different cell types in
77:00 And an easy way to prove that is not true is take food,
77:05 it in your mouth and roll it your mouth, like like a
77:08 Does it change its flavor as it around your mouth? No. All
77:13 . It basically is the same no where it goes. And that's actually
77:18 the taste map is really supposed to . All right guys, I actually
77:23 the whole class. I didn't I thought I was gonna miss,
77:28 have class next week. Then you to go on your vacation. I
77:33 it's the way it
-
+