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BIOL 3324 Human Physiology - 3324_lecture22_1116
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00:04 All right. What? I think ready to get going and we're just
00:10 jump back just a couple slides to ourselves what we're talking about? We
00:16 talking about there being three different phases terms of signaling or regulating digestion.
00:23 right. We have the initial which is the same phallic phase followed
00:27 the gastric phase, followed by the phase. Oh, by the
00:30 we're gonna be talking about the digestive today. Mhm. You guys remember
00:33 we were eating? Do you No, no, not just a
00:40 because the big burger, the big burger with the cheese and the
00:44 , except if you're alone and you eat the bacon, right? And
00:49 if you're a vegetarian, you're kind screwed. But we're going to go
00:51 and just pretend like all right, , whatever. And then we're just
00:54 stack whole bunch of stuff on top it, plus the fries with
01:01 What's that? And a cookies and , milkshake extra large. So we
01:05 the extra thing on the side because the only way to live,
01:12 So, with the phallic phase we said, hey, look, when
01:16 smell food, seafood taste, you , just anything, any kind of
01:20 with the food, our special senses , hey, you know what,
01:24 let's go ahead and signals through the and tell the stomach that foods are
01:29 , Right? So that's like when smell food when you walk by these
01:33 trucks between classes and you take that old whip and you're and you just
01:37 your stomach. It's basically what's it you? It's telling you it's time
01:42 eat that food right now. All . And so that's what's going
01:47 And so we're doing is we're preparing stomach for the incoming meal. And
01:50 we're doing is we're starting to create hydrochloric acid in the event that the
01:55 shows up and we can start causing Dean maturation. Now again through the
02:01 nerve. We're primarily working through a of Colin. But this is also
02:04 to signal through these other mechanisms that already talked about. All right,
02:08 we're talking about the gastric phase now said the gastric phase, the food
02:14 there. Okay, So what we is we have barrel receptors, they're
02:18 the distension. Alright. We're looking the increase in ph and I say
02:25 . It's really the drop in the as your acidic levels rise. That's
02:29 I was trying to get as acid rise to ph drop. So,
02:33 chemo receptors are indicators of food is our bellies. And what we're doing
02:38 is we're sitting against signals back to medulla and saying, hey um let's
02:43 ahead and keep promoting this process of for digestion. Now, when you
02:48 proteins. We talked about the G G cell signal for gastric to be
02:53 . We're also going to see that is uh these particles are going to
02:57 on into the intestine, they're gonna uh to the duodenal isosceles discrete polycystic
03:03 , and they behave in the same . All right. So simulate muscle
03:09 , the churning right, more hydrochloric , and then contractions in the pilot
03:16 . Now, why would I want contract the pilot sphincter? You know
03:19 the pilots shrinker is? Right. between between the intestine the stomach.
03:23 ? So why would I want to that? What do you think?
03:29 huh. Here, you did not jump. All right. Have you
03:34 eaten food so fast? You're just even bother chewing. I mean,
03:39 not I'm not judging. This is judge free zone. Right? I
03:42 , you have a food in your when you see it. It's just
03:45 you know, just hawking the food . Right? And what has to
03:50 is you have to break that down enough so that it can spend some
03:54 being chemically digested. And so what's going on in the stomach saying
03:59 that is too big? You didn't the proper mastication. So we're not
04:05 that go forward until it gets broken to the sizes that we need to
04:08 going to spend a little bit of . They're a little bit All
04:12 But when we were deal with the phase now, this is only about
04:16 of the gastric response. Alright, notice the intestine is talking back to
04:23 stomach and basically as the peptide start up come the pep tones,
04:28 What they do is they cause the to signal back to the parietal
04:33 Hey, let's start secreting hydrochloric acid break things down even further. All
04:39 . So we do have a signal the intestines. So that's what the
04:42 phases and so after you've eaten a again, you can, if you
04:46 want to think about the cheeseburger, can think about what's coming up here
04:49 thanksgiving all that, all that food gonna be in your belly with your
04:53 pants. And then he said after meal, that's when the intestine is
04:58 its job, right, stomach is its job. But the intestine has
05:03 be speaking back to the to the as well. So the first step
05:08 is the gastric empty. This is space that we want to get
05:13 But we haven't actually reached when we've eaten, right? When you're feeling
05:19 , that's the gastric feeling. Or the gastric full. Right? And
05:24 what is Castro Company emptying? we're going to start with the process
05:28 churning and so there's three steps, a propulsion step of grinding step in
05:31 retro propulsion step. So, I you to envision All right, We
05:35 about the different parts of the We said primarily the body is where
05:39 of those food is stored. But we have here is we have thickening
05:43 of smooth muscle. So up here the fund us and working our way
05:47 the body, it starts off thin it gets thicker and thicker and thicker
05:50 thicker. All right. Now, know how muscles work If I don't
05:53 a lot of muscle? Do have lot of strength? No, If
05:57 have lots of muscle, do I lots of straight? It's just you
06:02 . That's that should be an okay . Yes. All right.
06:05 you can imagine imagine I'm creating these tick waves and I'm starting off with
06:11 little smooth muscle. So I get little squeezing. But as I go
06:15 to get greater and greater strength. so what I'm doing is I'm squeezing
06:18 further and I'm pushing that material forward the pile oric region into the
06:23 Right? And I'm slamming it up that pile. Oryx sphincter. All
06:29 , carol, Make a fist, can do it like this if you
06:31 to eat meat. But then I you to turn it. I need
06:33 to look at that little tiny hole you've created that is about the size
06:38 the hole in the pilot sphincter. looking at it. So all the
06:42 have to be small enough to squeeze there. But Dr. Wayne.
06:45 I was a kid, I swallowed 3/4 and I pooped them out
06:49 Well, yeah, it's not going break down the quarter. It's going
06:52 push that through. But most of food basically doesn't have the strength that
06:57 quarter does. And so what it's to do is it's going to hit
07:02 and then it's going to bounce That's the retro propulsion and it's running
07:07 the food that's coming towards it. so basically, if you take two
07:10 that are grind, blowhard picture in hand cupcake over here, in a
07:14 over there and you jam them Are you gonna have to solid
07:19 No, you can have lots of and that's what your food is
07:22 It's basically bashing food against food. your stomach stone. All right.
07:28 , if you can't picture this, want you to think back when you're
07:32 , oh, I don't know, years old, you still took baths
07:35 . I know you still take Men do not take baths were not
07:39 to because we behave like six year in our bathtubs. Right? And
07:43 remember being in the bathtub, you in the bathtub, you start rocking
07:45 and forth. Guys remember that. get that wave going, you never
07:50 this. You never got the waves . All right. And so like
07:53 get it going good enough and it starts moving with your body and you
07:56 that way that's big enough and it blues and it's like, yes.
08:02 then your mom comes screaming in at going, what are you doing?
08:06 is dripping from the ceiling. All . And that's the last time you
08:11 a bath. You don't remember that that was so long ago. But
08:17 why you don't take baths anymore. doesn't want you taking baths because you
08:20 messes. All right. That's what's on here is you're taking all those
08:26 juices and all the stuff in there you're slamming it towards the pilot sphincter
08:30 it slams up against there comes back the food that's coming into it,
08:34 it down mechanically. And then when getting small enough, it squirts through
08:40 pile or sphincter like perfume through an . You know, an atomizer ist
08:46 looking at me like the game you knowing an atomizer is all right.
08:51 many of you guys use perfume or ? All right. When you press
08:56 body a little scorcher, right? about what's in the bottle. Is
09:01 liquid? And then when you press out, what is it? It's
09:04 mist that's called an atomizer. see you thought you were just learning
09:13 in here now I'm teaching you stuff you should know already atomizer. So
09:18 it's small enough here it goes and gets slowly spilled into the dewan.
09:29 right, Particles at a really less than two are the ones that
09:33 through, I guess I put it . All right. Now how do
09:39 affect this? It is easier than think there's a big long list of
09:43 here, but it is really Right? First off the amount of
09:46 in the stomach and the fluidity of stuff is going to determine the rate
09:50 gastric campaigning. All right. You hear like fa Alright, fuzz
09:57 Right? We all get the large , right? We eat it and
10:00 we eat it, we're like, , I can't believe I ate the
10:02 all of the fun, right? then about 15 minutes later, it's
10:05 , I'm hungry. Why? What's , primarily bra It's liquid. It's
10:12 liquid food. So you take the food in, it goes through the
10:15 sphincter just fine. And that's why get quick gastric emptying. All
10:21 Think of something that's more solid Here we go. Steak with
10:27 I'm not saying eat the steak with , I'm just imagining what stick with
10:30 . It's a cheeseburger. All uh huh. Put that in
10:36 And what you have to do is have to grind it down, breaking
10:39 , tearing apart stuff like that. gonna take forever. Think about what's
10:43 in a couple of days. Many you are going to celebrate with turkey's
10:47 , you're going to eat so much that you can feel it up against
10:50 eyeballs because you're really you're an empty right? Just build and you're going
10:55 sit there and you're gonna be uncomfortable Oh, I don't know, pretty
10:58 most of the half of the first , whatever they're showing, right,
11:03 you're just going to lie there and for death. And then you're going
11:07 hear it's time for pie. And like, I will find room,
11:12 ? And you'll have the pie and you'll sit there and pray for death
11:14 longer, Right? But again, that's solids, it's going to take
11:19 to break it down. So that's one, that's what that's going on
11:22 the stomach. But in the small and it's on the other end,
11:24 been it's basically looking, seeing what receiving. Alright, so the first
11:29 it does, it looks for fat because notice how much fat digestion have
11:32 done so far. Little right? did a little bit in the
11:36 You know, we need a little in the stomach, but we really
11:39 actually broken down fats. So if a lot of fat content, it's
11:43 slow down the rate of digestion because still need to break down fats.
11:47 so it's going to say, oh giving me lots of fats time
11:51 I need to deal with the fact you're giving me before you send me
11:54 fats as an example. All right the vicinity of the ph is really
12:00 . That's an indicator that you're sending lots of uh digestive juice with lots
12:05 materials in it slow down. I've to deal with what you just sent
12:09 . So let me neutralize this and me deal with what you sent me
12:14 . Once the ph rises, that's indicator that I've kind of been dealing
12:18 what you've been sending me. So can go ahead and send me
12:21 What about hyper Tennessee? Here's a one, right? Think about a
12:26 . You've all taken your chemistry classes you can think about a protein.
12:30 is a long chain of amino If I give you one chain,
12:34 not a lot of that's not a of material is just one thing,
12:37 ? One item. But if I breaking it down right then I end
12:43 with a lot of peptides. So tennis city goes up, right?
12:48 so now what I'm dealing with is dealing with the process of digestion.
12:51 haven't absorbed it yet. Slow I still need to deal with what
12:55 sent me to see. So you're with that. The question of what
13:00 I being delivered? And lastly, distension basically if there's too much time
13:05 if you if you send me too time out, let me deal with
13:08 you sent me now you can think that this like an inbox. When
13:11 inbox is full. Please don't fill inbox any further, Right? That's
13:15 idea. Okay and again those are all those neuronal and those hormonal.
13:21 vagus nerve and other stuff. Those through those mechanisms that were regulating all
13:26 stuff. So that takes us to latter or the bottom part of the
13:32 system. Right? The lower gi . That's the small intestine and the
13:36 intestine plus a bunch of accessory organs there. I don't think I need
13:40 read them off to you write small in three parts. Right, William
13:46 . Um We're sorry, doing backwards on june Emily. Um All
13:51 And then large intestine. And we're going to do all the different
13:54 And we're just gonna just called large . And so then we have these
13:57 organs. When we talk about the digestive tract. We talked about an
14:01 organ in the mouth. What was ? Salivary glands? All right.
14:06 these are like salivary glands are sitting the side and they're the ones that
14:09 produce the enzymes necessary to finish up process of digestion. All right.
14:15 that's what all these are. The produces the pancreas produces the gall bladder
14:19 a place of storage. So, wants to be my mathematician today?
14:27 right. Good enough. All So you're just gonna do a little
14:29 of math. You might not want pull your phone out. You can't
14:34 calculus on your phone. Right. , I'm just teasing. Real simple
14:37 . All right. You have a because you have that look like I
14:41 to ask a question right here, if you want to put all the
14:47 extend all? So, the actual if we went cut you open,
14:51 out your small intestine, be about ft long. Put in 20
14:56 Okay, That's not very long, it? So that's good. And
15:00 , here, you can see the lengths. Right? And so,
15:03 we're talking about is from the where's my stomach? It's gone.
15:07 it's basically right there. And then all this stuff that goes with it
15:11 then it ends right there at the um Valve. All right. So
15:16 the system is? So that's all tests. That's about 20 ft,
15:19 ? All jammed right in your Now, you can look, they
15:22 different links. I'm not going to you, how long is this?
15:24 it basically shows you do want them . Its job is to receive the
15:28 from the liver and the gallbladder. sorry, and the pancreas,
15:33 The jejune um is where we're gonna be dealing with the process of chemical
15:37 , as well as beginning the process absorption. And then we continue on
15:41 ilium, where that's where we're going finally do the final stages of
15:47 Alright, So everything that we're primarily to get from that cheeseburger? That
15:52 of fries, that big giant massive and cream shake, we're gonna absorb
16:00 . Okay, so, what sorts characteristics of the small test and
16:07 Well, first off, it has folds. All right. So,
16:10 start off with about 20 ft. these circular folds are like the ones
16:14 if you think about the tube, this they're basically, creating like.
16:20 is going like So instead of it a tube like this, it's a
16:25 that goes up and down, like so and so you can imagine
16:28 I stretch that all out, this come out about this long, actually
16:31 three times longer. So three times is good. Just keep the running
16:39 . Right? So that's the first . And so we're increasing surface
16:43 So instead of having 20 ft of , we really have a 60 effective
16:47 of intestine because of these folds. right. Now, what this
16:51 They're like speed bumps. And hopefully you do is when you come across
16:54 speed bumps, you slow down. don't swerve like I do. And
16:58 to discover one of them at the speed. Right? And these are
17:02 over the place there throughout the duodenum the jejune. All right,
17:07 that's the first thing. That's these that create that kind of pattern.
17:12 then if you look at the what you can see, is there
17:15 little tiny finger like structures, these called the intestinal ville I All
17:20 And that increases the surface area. tenfold. So, how many feet
17:24 ? 600. All right. we're an effective Length of 600 ft
17:29 of these little tiny fingers. And what we've done now is increased surface
17:32 . So we increase the ability to materials as well as increase the surface
17:36 for secretion. Right now, within structures, you're going to see a
17:40 tiny arterials. You'll see a capillary . You'll see vineyards as well,
17:44 well as lymphatic capillaries. And we a special name for the lymphatic capillaries
17:48 these locations called lacked eels. basically the little tiny structures. And
17:53 you do a dissection, you're going see that there's this like white fluid
17:57 in black tails. Hence the It looks like milk. It's not
18:01 . It's basically how fat is being into the into the body because the
18:08 they use to transport fats are too to get picked up through the
18:13 That's why we need the lack All right. There's all sorts of
18:18 out here on the surfaces of these . We have the absorptive cells are
18:23 billets. Absorptive cells we have goblet , goblet cells are simply single or
18:28 cellular mucous glands. All right. , these produce mucus And what that
18:33 . It creates this protective barrier against indigestible material in our foods. All
18:39 . Let's think of an indigestible indigestible that we eat celery. All
18:46 Think of the little tiny particles that up the walls of celery. There
18:49 these little tiny pokey things that your don't like. Now, we could
18:54 ourselves all day long with celery and doesn't hurt. But you take one
18:58 those little tiny particles and poke a . It's not going to like it
19:01 that much. All right. And lot of the food that we
19:04 especially vegetable, vegetable based or vegetable foods have a lot of non absorbable
19:13 in them, which can be damaging your tissue. They're also good for
19:16 . But you can see they're damaging your tissue. All right.
19:20 that's what we're protecting against. And the smooth muscle and they're basically makes
19:24 fingers go up and down. That massage the food as it's traveling
19:27 helps to milk the lack teals. so basically moves, helps move
19:32 The parts that are down below the are called the crips of libre
19:37 It's a fun name to say not fun as canal of slim, but
19:41 know, still fun one. All . And so these are where you're
19:45 to find the structures that are responsible secreting things. So, if I
19:52 actually there's lots of fun little things there. I think we're going to
19:55 back to that second on the surface the micro of the villa on these
20:01 cells And on the goblet cells. going to see these micro Valli.
20:06 right. The micro ville. I here, you can see it
20:09 That's just the a pickle surface and goes up and down and creates this
20:12 border that creates an effective length increase about 20 fold. So, how
20:17 does that make us now? 12,000 . How long is a mile?
20:26 something? So, you have an length of your small intestine of being
20:31 two miles long. Think how big have to be if it was a
20:35 structure. All right, These are . And so all these adaptations are
20:41 to increase the surface area. That's the math. I need it.
20:44 , 12,000 ft. I always just sure that I do the math.
20:47 . Cause you know someone coming. not supposed to be two miles.
20:50 it's like, well, I think 12,000, you know. All
20:55 So, this structure these brush borders enzymes in them. So, there's
20:59 be enzymes that are being excreted or into the digestive tract. But there's
21:04 gonna be enzymes actually embedded on the of these cells that are gonna be
21:08 a role in the process of All right, of course. To
21:14 these things across the absorptive subjects. also have transport proteins now down here
21:20 the crips. Right. So, would be the crypt up here is
21:23 Villas. We have a whole bunch cells. So, you can see
21:25 have endocrine cells that are producing polycystic in all right. We have pan
21:30 sells their their to secrete antibacterial Why do you think we need to
21:35 the antibacterial peptides in our intestines? a good place for bacteria to
21:44 But also five second rule. We have crypt cells that can basically
21:53 absorptive cells and we have stem cells there at the bottom. All
21:56 And then there are also every now then you'll find sub mucosal glands that
21:59 found in the proximal regions of the again producing mucus to make it nice
22:03 slimy and slippery so food material can without damaging cells. All right.
22:09 really the key thing here is I've a mechanism to signal back to the
22:15 to tell it what to do. I have a mechanism to communicate with
22:20 accessory glands to tell them what to . Right? Remember we said whenever
22:29 looking at these things were going to four questions, what's being secreted?
22:32 the motility? What's the absorptive? are they digesting? So that's kind
22:37 how I'm walking through all these Right. So in terms of motility
22:41 have um peristalsis and segmentation. The of which is first to mix the
22:47 with the juices that are being secreted the pancreas and the liver. The
22:51 thing that we're doing is we're moving time forward through the tube tubes.
22:56 ? So we're starting to autumn. moving towards the june. Um
23:01 so we're pushing things through. And , that's I guess that's what we
23:04 . And then lastly, what we're is we're gonna be mixing. So
23:07 want to turn things over. So use the example of the gobstopper,
23:11 jawbreaker to get to the center of jawbreaker. You have to literally lick
23:15 top layer all the time. And easier to do if you want to
23:19 all that sugar in your body is crush it first and then just constantly
23:23 keep sucking on that stuff and you're to break it down faster and that's
23:26 essence what if I'm putting time if putting digestive uses on the surface of
23:31 time, if I'm mixing it, pushing the time into or the enzymes
23:36 . But I'm also bringing stuff that's out onto the surface so that I
23:40 absorb the things that have been So that's when we talk about
23:44 that's what we're referring to. All . Now, when you eat what
23:50 do is you have to make Alright? So the first thing is
23:54 fill up the stomach, if there's in the small intestine, it's going
23:57 push that out further and push towards large intestine so that you can make
24:03 to move things from the stomach into small intestine. You think that's also
24:06 for the small intestine to the large . What do you think? Five
24:11 in my small intestine. Do you I need to make room for food
24:15 in? All right. We're going get a little disgusting here. We've
24:19 to talk about making poop. Have ever noticed that when you eat shortly
24:23 ? About 30, 40 minutes later need to go, poop may not
24:26 to you may not go. You be like I'm not going to
24:30 I've got little kids that do I refuse a poop. Thanks to
24:37 forward to when you're when you have . I'm just I'm just letting you
24:42 . All right. Yeah. Well, because what you've done is
24:45 has to kind of move forward. large intestine you're going to see is
24:48 to kind of serve as a storehouse feces until it's time to defecate.
24:53 ? But if you eat food you to make room for the food that's
24:57 in. So everything has to kind be shuffled forward. And so that
25:01 to defecate is really a function of these different reflexes. You have what
25:05 called the Elias equal reflex. And have this the guest the gas really
25:11 reflex which is basically I'm moving food the stomach to the small intestine and
25:15 using moving stuff from the small intestine the large intestine. And then the
25:19 in the large intestine is just trying find a place to go.
25:24 Like it's a little bit of So primarily what you say is that
25:28 the pressure. So it would be stretch reflex, right? And we
25:32 spend as much time as I do the anatomy students. But when you
25:36 at the large intestine, we have little pouches which are called the
25:40 And so really what you're doing is kind of is really disgusting. You're
25:43 of plopping things from one hospital to next. And what you're doing is
25:47 withdrawing water from them. So there this kind of moon. But you
25:50 have a distinction, right? There's stretching. And so it's that stretch
25:55 the walls. That's a signal. it's time to go. Right?
26:01 let's talk about the pancreas. We're ignore the endocrine function because endocrine is
26:05 thursday. All right. We're going start with that on thursday. What
26:10 wanna do is we want to focus exactly remember were secreted out of the
26:13 . So that's why it's called Even though the digestive track look like
26:17 in the body. It's outside the . We've already talked about. All
26:20 . And so again, we're gonna dealing with a solar cells are gonna
26:23 dealing with duck cells. And what gonna be doing is we're gonna be
26:26 what is called the pancreatic juice. notice wherever we are we're just gonna
26:29 it whatever the juices. Although we call it oral juice. It's just
26:34 but it's gastric juices. And then we refer to the pancreatic juice is
26:39 secreted to produce the intestinal juices. right. It's just it just sounds
26:45 . No matter how you say juices who? All right.
26:50 we want to focus here on the and the duck cells. And so
26:53 a lot of words here, but say the same thing that we saw
26:56 the salivary uh glands. Basically we a senior cells they're there to produce
27:02 enzymes that are responsible for digestion. we have the duck cells which are
27:07 for neutralizing the acids that are found the gastric juices that are being delivered
27:12 the intestine. Remember when we talked celebrating? Like we said the same
27:16 , the Ask ourselves are producing the that breaks things down. The duck
27:20 are producing not bicarbonate, but they're sodium bicarbonate. Right? So it's
27:27 slightly different bicarbonate? But it's still a it's an alkaline substance to reduce
27:33 acidity. All right. And so they're very similar. It's just a
27:39 much larger gland. All right. multiple casino inter global duck. So
27:45 as you can see a duck duck of joining together and they're getting bigger
27:49 bigger and bigger and they empty out join up with actually join up with
27:53 duct from the liver. Now, do they do? Well, pancreatic
27:57 producing about 1.5 liters per day. lot of pancreatic juices. Right?
28:05 produce a lot of proteins. What the most dangerous cancer? Anyone know
28:11 that you're almost guaranteed to die? , pancreatic cancer. If you didn't
28:18 the answer, you can probably guess we're talking about the pancreas right?
28:21 you hear you have pancreatic cancer, mean it is, it is like
28:24 I have a death sentence. It one of the most horrible things to
28:28 if you have cancer. Like if hear, oh, I've got testicular
28:32 , guys, it's like whatever. deal with it in a couple of
28:36 , a couple of months, couple whatever, whenever I have the time
28:39 golf games. All right. And from there they go. Kind of
28:42 , right? Pancreatic is the one it's like, ok, I've got
28:46 start making arrangements right? It's It's horrible. And the reason for
28:51 is because of this type of activity is doing is producing so much activity
28:55 doing so many things that when one these things goes wrong, that's why
28:59 so dangerous. All right. And what is it producing well, is
29:03 these things called Zeus imagines Zim regions the enzymatic precursors. And so you
29:09 probably see here you have the region the end. So trips, Imagine
29:12 trips, imagine these are enzymes that responsible for breaking down the proteins.
29:17 also have a whole bunch of other of proteus is pro car boxy proteus
29:22 our produce that work from the the box the end of the peptide.
29:26 , we got some pep. Today's like the trips energy and climate
29:31 Imagine which is they're breaking down peptides the middle. But what we're doing
29:35 we're saying we're throwing the whole house the peptides to break them down.
29:41 , ma'am. Mhm Yes. And , Why? Why? Why would
29:49 release them in their inactive form? . I can barely hear but I
29:56 what you said because you raise your with such confidence is that your
30:00 If you have them in their active , they break down the cells that
30:04 produced in and the proteins in those . So having them in their inactive
30:10 and stored away in their active inactive doesn't harm the cells that produce
30:14 It's only once they've been released that get cleaved to become active.
30:19 for example, if you have not any of these enzymes trips in,
30:24 example, looks for licensing all it is if I see a license,
30:27 gonna cleave at the life seen. , it's just reading a long life
30:31 listening. Listen, it doesn't care the protein is, as long as
30:36 finds license, it's gonna break those down. All right. And then
30:41 have a whole bunch of other enzymes pancreatic amylase. So you can see
30:45 breaking down proteins. I'm breaking down . I'm breaking down fats. I'm
30:52 down nuke laich acids. So I'm the whole house at what's left
30:58 So, even though I started the of digestion in the mouth and I
31:02 breaking down carbohydrates that began breaking down . Most of the pro uh most
31:09 the digestion is occurring in the trying to find the spot that works
31:14 . All right. And then we to create an environment. I guess
31:19 also producing sodium bicarbonate. So, thing. Alright. We're creating an
31:24 which all these enzymes work. So, remember the kind coming from
31:32 stomach has a very very low ph two. And so, what we're
31:36 is we're putting into an environment where raising that ph up into about
31:41 And what you're doing is you're basically off all the enzymes that were released
31:46 the stomach, the gastric lip You know, the pep senate the
31:51 in. You're just saying we don't you to do your stuff anymore.
31:53 only want these enzymes to work. their job is to break things down
31:58 the digestive track. Mm hmm. , you're always always always producing very
32:06 levels of these digestive proteins. And always being secreted. So, it's
32:11 this constant production. Remember we talked constituent adverse regulatory pathways when you get
32:18 that's when it up regulates everything. so again, this is the ascending
32:22 , the colon cystic kind and the . R. P. All
32:25 And they're just doing the things that already described before. We're acting on
32:31 cells that result in the production of imagines and these enzymes not only in
32:37 pancreas but also in the stomach. we're basically telling everything, throw all
32:44 enzymes we have available to get the to occur. Now whenever we drive
32:52 car we're not just going to use gas pedal. Well so are we
32:57 to use the break? Not so in Houston but we try right if
33:05 speeding up towards that yellow light and turns red if I'm still 100 yards
33:09 I'm probably going to stop right. the only way I'm gonna stop if
33:13 already going 80 miles an hour is I slam on my brakes. So
33:17 everything that turns on we need to something that turns off and these two
33:21 are the two of the molecules that use to turn things up. Now
33:25 aren't the only ones but these are two big ones peptide yy basically when
33:30 have lots of lipids in the distal that's used to block the asner cell
33:39 . Alright, lipids in the in distal small intestine Samantha Staten where these
33:44 produced by the D. Cells as as the pancreatic delta cells that's what
33:49 should be and what they do is serve as that negative regulator. Now
33:53 we're talking about this earlier with histamine status and stuff, we said the
33:57 same thing. Simvastatin is a negative of digestion slows things down slow secretion
34:04 . So what are we doing in of duck cells? So what we're
34:08 about here is asking ourselves, asking . So what we're doing is the
34:14 , How do we tell the duck what to do? Well, the
34:17 important regular is a molecule called secret produced by sl's. What it's doing
34:21 it's responding to increased acidity. All . If I have low ph that's
34:28 sign. I got lots of time it's time to start digesting. So
34:32 start increasing the amount of secret It acts on the duck cells to
34:36 producing the bicarbonate. Which neutralizes the which allows my enzymes to work.
34:43 just secret in is the easy And then you can see what are
34:45 other ones involved to see the cooling GRP which seems to be everywhere.
34:50 ? And then to turn everything off have substance p. So if Secretary
34:56 it off. System P turns it . On off. So I throw
35:04 up here just to kind of remind right. I've got this phallic fade
35:08 we're going to support support or start production of the enzymes. Gastric
35:12 We're now depending on the presence of to continue the process of of
35:18 and then we get the intestinal phase now it's the presence of the broken
35:21 materials, the peptides and the We're talking about lipids. It's not
35:25 triglycerides. It's the break broke the , the monocle Lyssarides and the fatty
35:33 that play a role. We're talking the peptides. It's not just all
35:36 peptides. It's some very specific The ones your bodies can't make the
35:43 . Name Me. one Essential Amino . You should all know this
35:49 This is the one that you should know which is the one essential amino
35:53 . You have to have to have me why it's the start amino acid
36:03 have to have that. It's an amino acid. You fail to make
36:08 failed to get to your body The essential amino acid, I believe
36:12 definition are the ones you have to in your diet. Huh, there's
36:17 amino acids Right? There's 20 of Actually, there's more than that.
36:22 20 of them. We used to all the proteins in the world.
36:25 right. So the essential ones and are several All right back up to
36:35 to I think, I can't Do you remember there was that page
36:40 was talking about the sensual amino acids general? And they have they talked
36:44 vegetarians said vegetarians have to have a diet between the leg umes and the
36:50 greens. Do you remember this No, There's even a picture usually
36:55 a picture of corn and have a of beans. And they're like,
36:58 like in every textbook and it has list of amino acids that each one
37:02 them provide. And there's some overlapping . But legumes have some essential amino
37:07 that corn doesn't have. And the greens and like things like corn contain
37:13 amino acids, but there's certain ones the leggings don't provide. And so
37:16 you don't maintain a balanced diet as vegetarian between the legumes and the leafy
37:21 , you're gonna be missing certain essential acids which will lead to uh sickness
37:28 illness in your body because your body produce these. And it's not getting
37:33 this now kind of sort of It's , oh yeah, that was like
37:36 years ago, rattled my brain a bit. No, I don't remember
37:40 at all. Do you still have biology textbook? Go check it
37:43 It's there. I promise. Every has it. All right. That's
37:48 we're talking about here. Is the is looking for those essential amino
37:52 And so what are we gonna We're gonna absorb them all these things
37:56 we're breaking down through the small Now. How much fluid you get
38:01 your diet is about 1.5-2 L per ? Not that much, is
38:06 I mean how much water you supposed drink every day? You don't know
38:13 know? You see the guys walking with their bottles of water. Big
38:18 . What It's supposed to be? , eight cups. Some people they'll
38:22 you no, no, it's a . Yeah. You know what the
38:26 answer is? No one knows because never done real experiments. So it's
38:31 like, how many steps am I to take in a day?
38:34 Why? Because a company in Japan that was a good round number.
38:39 , it's done the experiments to figure out. All right. That's what
38:43 for. Okay. So we don't how much water, but in essence
38:47 you eat meals and stuff, you water in and there's water in the
38:51 that you're consuming and that's about one two leaders. And so what you
38:55 is you absorb about 6.5 liters out the digestive system. Price. That
39:03 You're going or you're you're going to going to produce water or borrow water
39:08 your body. So your total load about 8.5 Right? So if you're
39:13 too in that means you're probably doing 6.5. If you look at all
39:17 water that was in the digestive If you basically closed it off and
39:20 at how much is there? It's 8.5. And that means you're absorbing
39:24 6.5 back in to your body? means you're getting rid of the rest
39:29 it. All right. Now, are you gonna be absorbing?
39:35 I've already taught you the secret What's secret? Remember about absorption where sodium
39:43 ? Water follows wherever water goes. the osmotic considerations everything else follows.
39:51 learn that you've like said you've mastered unit, Right? And that's what
39:55 saying here. Look, net absorbs favors water, sodium, chlorine,
40:00 and other fun stuff going in. the secretion favors bicarbonate going out to
40:05 . All right. So, if look at sodium, there's both passive
40:08 and active absorption in different places, areas. And when that happens,
40:13 follows and wherever water goes, then else is gonna follow sodium just like
40:18 did in the renal system. All . They're going to use passive transport
40:23 are gonna use coast transporters. There be pumps involved. There's even exchangers
40:28 notice I'm not spending a lot of talking about each of the individual mechanisms
40:33 you already understand if sodium is being , water is going to follow.
40:37 means everything else is as well. right. So digestion. We said
40:45 homer again with his doughnut, Is accomplished by hydraulics. This
40:50 what is hydro assist, basically, put water you split the water in
40:54 , one side, gets a The other side of the bond that
40:57 broke gets a hydrogen. Right. now you have a nice stable
41:01 You just keep doing that over and again. All right. So,
41:05 we're gonna do is we're gonna take carbohydrates. All those policy sack arrives
41:08 the form of starch and glycogen. the dice, aka rides. Remember
41:11 we said they were Remember what they lactose to cross and beer? I'm
41:20 , Mall toes. All right. gonna break those down into the monas
41:27 glucose, fructose and galactose. All . What about the proteins? Were
41:31 break those down into amino acids are poly peptide. What about the
41:35 Well, we're going to consume them the form of triglycerides were ignoring for
41:38 now, the other dietary fats such cholesterol and whatnot. But there
41:44 But what we're doing is we're talking the triglycerides, which is our dietary
41:47 , which we're gonna break down in strides and free fatty acids.
41:50 all this stuff is really, really and simple. We don't have to
41:53 it complex. All right. let's talk about carbohydrate digestion. Look
41:58 all the horrible nasty pictures. Big giant chains of sugars. So,
42:03 do you do with Emily's and We're cleaving them down into smaller
42:08 And then what we do is when get the sugar small enough. What
42:11 have is we have enzymes in our borders that break down those complex
42:16 Like the dice Ackroyd's and the aka rides. And what we do
42:19 we turn them into the single mono rides and then we have carriers that
42:24 move those materials forward. So, example, here is a glucose co
42:31 . What is it co transporting with wherever sodium goes, Water follows.
42:36 what we're doing is we're using a transporter to move glucose into the
42:40 Doesn't cost us anything. All These are showing you some other
42:45 Just showing you longer approach or longer and showing you how we break them
42:51 . All right. So enzymes are secreted enzymes are also being found in
42:56 brush border to break sugar's down from chains down to itsy bitsy tiny mono
43:01 rides for transport. And we have mechanisms for transport. Sugar goes in
43:06 body. We talked about the story Gatorade. Right. Yeah. What
43:18 proteins? Well, we've been breaking down from the from basically the stomach
43:24 proteins into peptides, into pep tones smaller peptides and smaller peptides and smaller
43:29 . And finally we get down to absorbable peptides. So we're going from
43:34 are all ago. So many amino . Right, So individual amino acids
43:38 be transported across using a cone transport . But here we have a series
43:43 peptides that are embedded in the brush . And what they do is they'll
43:47 like Tetra peptides and break down into peptides and there are actually transported for
43:53 peptides. We have di peptides that be broken down from the tri
43:57 And we have transported for the di . And then we can take a
44:00 peptide and bring them down in amino . We already talked about that.
44:04 once you get it down to a enough size, about four amino acids
44:08 length, we can start absorbing. we don't have to absorb force.
44:11 can break them down even further. of cool. Because you learn in
44:16 one you have to absorb amino So it's actually a little bit bigger
44:21 that. All right. And then they get inside well, there's peptide
44:27 in there to break things down as . Fats man, fats are the
44:31 ones. Mhm. You know what we do with fats? Well,
44:37 thing we need is we need to through the process of multiplication. You
44:41 , the modification is all right. going to use an example here so
44:46 you guys can understand you guys don't is see the women are nodding their
44:52 and men are staring at me like like, huh. But uh all
44:58 . There is a way to make tastes better. All right. One
45:03 the things you do is you put on it. Now, the best
45:06 are the nice yummy creamy ones. some of you are like looking at
45:09 like whatever dr Wayne. I like nice light ones. Like a vinegar
45:14 oil. Yeah vinegar and oil, have vinegar. And you have
45:20 And if you put them on they basically create salad soup, which
45:25 gross, which is why men, men don't eat salads, castles are
45:31 , they might be good for but they're gross. Yeah, swear
45:42 just watching and eat. It's really funniest thing on the planet and you're
45:46 because it's true, right? So you go to a restaurant, if
45:55 don't have the vinegar and oil and things where you make your salad,
45:58 usually put the vinegar and oil in bottle together, right? And the
46:03 and oil are one is acquis, is fat and fats put into an
46:07 solution are excluded. So you end with fat on the top and you
46:10 up with that acquis vinegar on the . And if you take that bottle
46:14 turn it over, the fat goes to the top and the vendor goes
46:17 to the bottom, so you end with the same thing, you end
46:19 with, you know, salad So what do you have to do
46:22 order to have a proper 1-1 ratio and oil solution? What do you
46:29 ? I don't know, we're we don't shake anything here, we
46:34 . And what we're doing is we're a big old fat bubble. And
46:38 we're doing is we're breaking the fat into smaller bubbles, right? And
46:42 what you're actually seeing here, here's big old fat bubble. And you
46:45 see there's smaller and smaller bubbles. , there's different ways to emulsify.
46:50 can impulse if I through the process mechanical disruption shaking. Right.
47:00 Or what you can do is you use something that can sit in the
47:04 and tear it apart. All And so that's what we're going to
47:08 to do is we're going to multiply fat because in essence, if we
47:13 our fat, we're going to create surface area. That's number one.
47:17 , it's gonna be easier to digest uh simultaneously it's Well, it's the
47:23 thing about easier digest. I'm trying think there was something else I
47:26 I'm probably gonna come to something here a second. All right.
47:29 the way we do this is we a little space. All right.
47:32 , we started in the mouth that salivary pace. We did a little
47:35 in the stomach. That was the cliff pace. But now, what
47:38 gonna do we're gonna start working with pancreatic lip bases. Right? So
47:45 is the materials that's going to allow to mull sif I facts. All
47:50 . And what's in bio There's a bunch of stuff and bile. But
47:53 key thing here, All right, the bile salts is what we're looking
47:58 . All right. So, there's whole bunch of stuff you can see
48:00 there, and you're making tons of . You know, almost a liter
48:03 day. All right. Which is we have a gallbladder to store that
48:06 up. All right. But it's bile salts that help this process.
48:11 what it does, bile salt is is an anti empathic molecule.
48:16 meaning that it has an attraction to , but it also has an attraction
48:21 facts. And so what it does it adds absorbs itself into the
48:25 Not notice that absorb it absorb. so what happens is is that the
48:30 sinks in and goes into the fat goes, uh this is where I
48:34 to be. But then it has tale that sits out that's polar that
48:38 out in the water. And when have a whole bunch of bile
48:41 what they're gonna do is we're gonna inserting themselves like radiated molecules on the
48:47 . And those negative charges are going do what to one another. They're
48:52 repel. And so, if you repelling and there's no place to repel
48:57 . Then what's going to happen is gonna try to repel away from each
49:00 . So they start tearing apart the . So, notice this is a
49:05 modification. All right. So, is kind of showing you this is
49:09 fat droplet, right lipid DARPA? can see here I am with the
49:13 tiny negative tail sitting out here. what I've done is I've inserted myself
49:18 with a lipid. what you're gonna gonna have multiple layers. You can
49:21 these are multiple by layers. And inside you're going to have what are
49:25 core lipids. These are your some diocese Lyssarides. So basically you're
49:29 it apart and some cholesterol. But , you're gonna have these by
49:34 And then if you start inserting salt those, what's gonna happen is you're
49:37 start repelling each other. They're gonna each other apart and you're gonna have
49:41 that are but off. All So this is this is not the
49:45 , this is trying to show you I'm tearing this part off and I'm
49:48 end up with a smaller bubble. I'm gonna keep doing that until finally
49:51 the bile salts are equally distributed so all the negative charges are far away
49:55 each other. Now, I've got nice happy fat bubble. But that
50:01 that negatively charged tail is also a site for collapse and olympics. So
50:07 is there's it's a co factor that lips do its job. And so
50:12 comes and hangs out on that tail says, look, there's fats and
50:15 starts breaking down the fats. And what you do is you start tearing
50:20 these multiple by layers, right? they become from multi laminar to uni
50:26 until ultimately they become this structure is a mixed my seal. And so
50:31 you're doing is basically you have you have triglycerides. You have fatty
50:35 , you have all the different fat that are in there. And what
50:39 doing is anything that can be torn or broken down are going to find
50:42 way into this outer layer and things gonna be absorbed along the way.
50:47 , you get this little tiny structure only made up of the smallest things
50:51 can be absorbed. So, here's whole thing kind of being put
50:58 So, here's my emotion droplet. I start breaking it down via the
51:03 salt until I form mixed my And then what's going to happen is
51:07 start moving up against the wall of intestine and are three things that can
51:13 , fatty acids can diffuse across the itself. All right, they're not
51:19 . So, they can basically move and easy across the lipid bi layer
51:24 the absorptive cells. I can get into the plaza memory. This is
51:29 process of collision. But I also transporters that can actually transport fats into
51:36 cells. So, one of three can happen. I can go across
51:40 I'm gonna go now I'm inside the . I can be incorporated into the
51:45 or I can be picked up and across. And I'm basically taking that
51:49 my seal. And I'm just slowly this stuff into the cells. And
51:53 I finally just disappeared. Nice. , we haven't gotten there yet.
52:02 a good question. I was okay, tell me you gave me
52:05 over here. Tell me what's All right. But we just got
52:09 fat inside the cell. Fats don't being in water and we need to
52:15 them to places. I've got this storage system of fat, right?
52:21 of us do minds right over See, look, look at
52:25 please. Yeah. When the world crumbling down the next couple of
52:30 I get to survive a little bit than the rest of you.
52:33 All right. What happens is is get picked up processed. So like
52:39 free fatty acids and glycerol triglycerides, get joined together and they're formed into
52:46 . Right? Triglycerides are an incredibly way to store up energy. And
52:51 what I'm gonna do is I'm going reprocess them and I'm gonna process them
52:55 put them together with proteins. And gonna form these structures called kyla microns
53:01 they're gonna be formed in the golgi they're stored inside vesicles. And then
53:05 vegetables are moved to the surface and kyla microns is now released outside of
53:10 cell but they're too big to go the capillaries. So what do I
53:17 ? I move that Kyla microns into locked steel and from there it moves
53:22 the lymphatic system goes all the way . Gets mixed in with all the
53:27 lymphatic fluids and then it joins up the regular circulation to finally arrive at
53:33 final destinations to wherever the fat needs go. All right now, this
53:38 also true for VL deals with regard the liver. The liver makes VL
53:42 VL deals are transporting fats to places use or storage HDL and LDL
53:50 You guys have learned these. Right. Those are transporting fats that
53:55 been stored and they're mobilizing them for . All right. So that's kind
54:00 the easy way to remember the LDL Kyla microns are a way to storage
54:06 and LDL are from. Okay, . Great. This is awesome.
54:14 , we know what the liver Liver produces the bile salts, bile
54:18 helped bring down the fats, the from the pancreas break down the fats
54:22 allows me to absorb the fats. , how do we regulate these
54:27 Well, here we go again. Coley. Sister qian in what is
54:30 a sister kind of doing when you fatty kind. I want to release
54:35 pancreatic juices to break down the All right. What about the
54:41 Remember Secretary is acting on the duck ? I want to create the environment
54:45 that the enzymes can do their All right. So these are the
54:49 big ones. And of course vagal as well. We're down to the
54:55 two slides. How fast did I today? I went incredibly fast.
55:03 didn't even need to come in here this thing to tell me how much
55:07 . But it's an easy process, ? I mean, ultimately, when
55:11 look at these things, I we could go there and name every
55:15 . I could force you to learn all and then you'd hate me.
55:19 this, You're already you're like, , don't even try me,
55:23 But they're unnecessary, right? As as you know, I'm breaking down
55:27 , I'm breaking down carbohydrates, I'm down fats, I got the enzymes
55:31 to do it. You know how name an enzyme if it has
55:34 S. E. At the it's an enzyme and then sometimes it
55:39 . Alright, so finally, we all this material. We have absorbed
55:43 the material from our small intestine. left in the small intestine is that
55:47 could not be broken down or So everything that's ending up in the
55:52 intestine is what our body can't deal . So, we've got all this
55:57 that goes in the large intestine, of it is water and salt plus
56:02 other stuff. But we borrowed a of water, there's three regions to
56:06 them. So here's your seat them the colon and then down here is
56:09 rectum. So there there's your anatomy the day and there's actually names to
56:14 this stuff as well further down all . It's only about five ft long
56:19 its job is to take about one of that digest material. You broke
56:26 down but you couldn't absorb it and couldn't break it down any further.
56:29 it's supposed to deal with this. right. So it's supposed to convert
56:35 we call Kym that liquid that's been through into feces. That's number one
56:40 . So the water that you borrowed you can go kind of say says
56:45 am I getting my water from? is where I'm getting it. What
56:48 I doing? I'm re absorbing it right. So left over water is
56:51 reabsorbed from here and then I'm also with the water. So sodium,
56:57 it goes, water follows teams learn once. You know it every
57:02 Right? So if you have about liters of water remaining you absorb about
57:09 L. That means you have about mils of water left over in your
57:13 . What happens if this mechanism breaks diarrhea? That's all diarrhea is it's
57:20 feces that still hasn't water with it I guess you can't really call it
57:25 at that point because you the water helps create that that fecal content right
57:34 because you have all these indigestible stuff you have wonderful bacteria hanging out in
57:39 digestive system going oh bring me the . I'll break it down. You
57:44 to protect your body from that. there's a lot of alkaline mucus there
57:48 basically serves as a barrier between those and their secretions? Um And also
57:54 indigestible. And then what you're doing you're basically moving so these are the
57:59 . So what you're doing, you're moving the feces like plopping it from
58:04 section to the next all the way . All right. And you start
58:08 until it's time to defecate. Just like your bladder. Is there
58:12 store urine until it's time to That's primarily what these ladder regions of
58:21 large intestine are for. So I've water, sort the salts, an
58:28 material. Give it to the bacteria. Give me stuff in
58:32 vitamin K. For example. And store stuff until it's time to
58:38 So we've learned how to turn a with a side of fries a big
58:44 milkshake in the poop. So you call your mom said last week.
58:48 learned how to pee this week. learned how to poop and they'll be
58:53 proud of you. They're like I'm glad we're spending all this money for
58:56 to take this class. Remember what said on the first day when we
59:03 this this is not hard. You actually just create a matrix. This
59:08 an example. This is the simple of that matrix, right? You
59:14 literally just say where am I different . Remember the areas are defined by
59:19 sphincters, right? And all I do is ask the question, what's
59:23 on in my mouth. What's going in the esophagus? What's going on
59:26 the stomach? What's going on in small intestine? What's going on in
59:29 large intestine? Can I break it between motility, secretion, digestion and
59:35 . And when I do that, mapped out the whole digestive system you're
59:39 to find. It literally takes a of everything that you need to
59:44 It's kind of cool one time, this is the last thing I wanna
59:48 . This is our last life. time. I didn't have my charger
59:53 my laptop. My laptop died. didn't have a backup copy of the
59:58 . Had to had to get up and I had a lecture giving a
60:01 talk. That's when I go up the board and actually draw everything
60:05 And that's all I did is I did the matrix. I said,
60:08 are the different structures. This is we do. And I just walked
60:11 , I started writing everything down. you can do that, you've got
60:15 system down. Easy mode. When come back on thursday thursday endocrine
60:21 And again, it's gonna be a through it. We're primarily gonna be
60:24 with the enzymes, Sorry, the hormones regulating uh uh growth and digestion
60:33 some other things of absorption. And after that reproduction, reproduction. Why
60:42 live for the whole semester? All . You guys have a great
60:44 Glad you guys stuck around. Mhm . So,
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