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BIOL 2301 Human Anatomy & Physiology I - 2103_lecture05_0201
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00:03 Alright, It looks like everything is So I don't like that's way too
00:11 . Might push this. Mhm. see if that works. Alright.
00:20 have two goals today. Alright. first goal is to uh talk about
00:27 the function of proteins are in the , like in a very, very
00:32 way and how we get proteins to they need to go. Alright,
00:37 , that's kind of what the first is. We're gonna start where we
00:39 of left off of protein synthesis and gonna talk about that and then about
00:43 through we're gonna change gears, we're ask the question. All right,
00:47 , cells were not really asking this , but this is what it's gonna
00:51 into. Cells talk to each other order for a tissue to be
00:54 Cells need to communicate, right? remember tissues are made up of
00:57 cells have to communicate with each other ensure that they're doing the job that
01:01 supposed to be doing together. so, the second half is to
01:05 the question or to begin creating the to ask that question of How do
01:09 actually talk to each other? The lecture is really about how the cells
01:13 to each other. Okay, we're going to be looking at some
01:17 basic interactions or or activities that the do. And if a third of
01:25 don't fall asleep by the end of lecture, then I did something
01:31 It's that boring. Okay. I , it is. Alright, So
01:36 gonna try to do try to do to try to keep it kind of
01:40 . Hopefully we'll see. All So our starting point is here with
01:44 synthesis where we left off and we look um in order for it to
01:48 functional, it needs to make its . It has a blueprint called
01:53 N. A. Right from that . We're going to create specific instructions
01:59 go to use to make that And so we're looking at is that
02:04 . All right. And so there's steps that are involved here transcription.
02:07 said is taking D. N. . And and making a copy of
02:12 making an RNA copy from that Specifically looking at a single gene.
02:17 right. And so we call it . Why? Because when you transcribe
02:21 it's basically making a copy. When you transcribe someone else's homework,
02:25 are copying that homework. That was example I use then we said All
02:30 , well, we got translation. . We kind of know in terms
02:34 I'm turning one language into another Right, So that would be
02:40 That's really what's going on here is translating the language of nucleotides and there's
02:46 specific code that goes with nucleotides into language of proteins which we said was
02:51 amino acids in the sequence of amino . Alright, So that's where we
02:56 off. And what I wanna do I want to kind of look at
02:59 process of translation. Alright. And , we're not going into the level
03:04 depth that you would as a freshman biology class, right? We're just
03:07 of saying this is how it goes because you need to understand. It's
03:11 like cells exist and magic happens. that's what a lot of people
03:16 Right? I mean I had lunch a friend yesterday who uh is a
03:21 liaison officer, which is basically a who works for a farm company and
03:25 to physicians how things work. And current partner is completely clueless about how
03:32 works in some very simple things and an engineer. He's a smart
03:36 But we're just laughing about the things he doesn't understand because we do.
03:42 it's fun to laugh at people who understand the same things you do,
03:45 ? Or is that bullying? I remember. No, it's not bullying
03:48 . Only if you do it to face. Yeah. Okay.
03:52 So what we're trying to do in process of translation, we're making new
03:56 . And so there's a couple of that you need, right? The
03:58 thing you need is that M. that we talked about and we said
04:01 all this processing. So when you the gene, it's this long thing
04:05 has too much stuff in it that don't need and you're gonna process it
04:08 into something that's functional, right? that M. R. N.
04:11 . The M. Stands for messenger . So if you've got the Moderna
04:17 , the new one that is an . R. N. A.
04:19 . It's a new concept. The is that we're giving you a piece
04:22 RNA that RNA goes into your body the cells. The cells take that
04:27 they use this process to make a tiny protein that then alerts your immune
04:32 that there is something that's in your that shouldn't be there and that alert
04:36 immune system to start attacking things that like that thing you just made.
04:41 so conceptually it's a really neat It's something it's kind of something we've
04:44 trying to figure out how to work cancer research but it's not quite where
04:50 needs to be just yet. But know, opportunity presented itself. Let's
04:54 if it how it functions. All . So what we have here,
04:58 we're talking about the M. I remember is the sequence is matching
05:02 there in the D. N. . It's the code of the
05:05 N. A. Copied so that can then read it now in order
05:09 read it. You need a couple things. You need a ribosome.
05:11 ribosome goes along and reads that sequence as it's reading that sequence it's going
05:17 be looking at that code and it's to decode the code and in order
05:22 decode the code it needs T. . And that's what these little things
05:26 here. T. R. A matches the codes of that
05:31 RNA. And it does. So these three peats that you're going to
05:35 a little bit later called codacons attached the T. RNA. Those little
05:39 circles are representing the amino acids of protein. And so as the ribbon
05:45 goes along and reads the T N. A. Comes along and
05:49 where it needs to go and it with it the right amino acid to
05:53 with the code. And then what do is you start adding amino acids
05:57 top of the I mean to the and then you keep moving the chain
06:00 the chain begins to expand. And what this is showing you. Is
06:03 expanding chain of proteins which is the sequence based upon the sequence here in
06:10 M. R. N. So what does that sequence kind of
06:13 like? Alright, and so we're to be down here. This is
06:18 the code and how you'd read This is what you learn in
06:23 maybe in bio biology but not so memorize it. But basically what it
06:26 up here is is that, look you have this particular sequence you're still
06:30 uracil, that's red as a And so that means those that three
06:36 sequence is equal to a finale and what you're gonna put in that
06:40 And so you can see down what we're saying is is that if
06:44 is the nucleotide sequence for the RNA which would be equivalent to what
06:50 saw in the D. N. . Then what you're going to have
06:52 that china is going to come along read in the right frame.
06:57 So it's looking at the letters in right frame and it says oh when
07:00 see this code I'm gonna bring in . When I see this code I'm
07:04 bring in a glycerine. And when see this code I'm gonna bring in
07:07 and it's just gonna keep doing that and over again and adding them
07:11 So you can look at a snippet D. N. A. And
07:14 you know the proper reading frame and get rid of all that extra guns
07:18 we don't need that you'd expect to in the M. RNA. You
07:21 actually predict what the amino acid sequence going to be for protein kinda
07:26 Right? So what you say is D. N. A. Has
07:30 translated transcribed into RNA which is then into proteins. So if you look
07:34 the triplets in D. N. . And the right reading frame that
07:38 give you the coordinates that encode for amino acids. And there's always a
07:44 that's also stop code and there's three them that are stop code ons.
07:47 it tells you when to stop and when the protein stops. All
07:52 Have a basic understanding of how we amino acids. This is what it
07:57 kind of look like. Right? here you can see here's the rebels
08:01 here's that M RNA with that Right? And you're going along and
08:05 reading in this direction. And what's is is that you're bringing in new
08:10 into one of the slots. So you can see I've got a
08:13 Here's my expanding chain. And what gonna do is I'm gonna take this
08:17 . I'm gonna attach it to that and the ribosomes gonna move one frame
08:21 . The Expended T. RNA that no longer need falls out. Gets
08:25 amino acid and it goes back into queue if you need it.
08:29 it's this way of reading each of coatings to bring in amino acids and
08:33 get this long chain of amino That's your protein. Now, we
08:40 this picture earlier. We saw three three of these, I think.
08:45 right. And this is what it like. Now this doesn't do a
08:49 job. Also because our name this just an aside is not always a
08:53 chain. Really what RNA does. loops itself and attaches itself. Remember
08:58 modifications. I talked about the gap Iguanas in cap and that poly a
09:04 . They're attracted to each other. they create this loop. And so
09:06 means you attach and you just start around in circles over and over and
09:09 again. So you can make lots proteins from a single message. All
09:14 . It's like a xerox machine. that's what's going on up here.
09:17 you can see you don't have just representing one message. What happened is
09:21 pops on and as it moves down next one pops on the next one
09:24 on. And so you can make messages at the same time. And
09:27 was that electron micro graph that we at earlier. Right? It's just
09:32 you these expanded changes, right? moved down and read. So a
09:36 message gets you lots of proteins. kind of cool. And then this
09:42 be what would be going on when dealing with that rough ectoplasmic articular the
09:46 process. Here's your M. N. A. There's your ribosomes
09:49 along. There's you're extending protein and itself into the membrane here. It
09:54 expanding and being uh and growing. then finally, you have it inside
09:59 ectoplasmic curriculum. That would be a that you'd be secretive. But proteins
10:05 all over the place, right? have them inside the cell,
10:09 They do things inside the cell. said that's the machinery of the
10:12 We have them on the surface of cell and we have them secreted from
10:17 cell. So there needs to be mechanisms to allow that to happen.
10:22 and that's kind of where we're going is we're gonna we're not asking this
10:25 . What does this specific specific protein ? Because that would just take
10:30 We're just asking, generally speaking, do we get proteins to where we
10:33 to go? And then we look a system we can say,
10:35 here's this protein that's important. What it do? And then we can
10:37 that question. We're not gonna do with all 33,000 plus proteins that are
10:40 your body because again, it takes so far so far. Are you
10:45 me? All right now. I the maturation a couple of days
10:52 Do you remember that we talked about saturation instead of protein is affected by
10:55 and ph and so if it it it to unfold inappropriately. Well,
11:00 that implies is that there is a fold for protein. Okay, that's
11:07 of neat. So how does it there? Well, we're kind of
11:12 trying to figure that stuff out. what we have is we have a
11:14 of proteins called chaperone proteins. And , here you can see here's your
11:18 here's your rival's own There's your expanding protein as you go along. And
11:23 happens is a series of proteins come and bind up to and help the
11:28 fold into its proper positions so that becomes the right shape to do the
11:36 that it's designed to do now. you're like me, you're probably looking
11:40 going, wait a second, there's of proteins out there. How does
11:42 know the shape of every protein? question. I don't know.
11:48 I don't think we know very well or why, but I think what
11:51 has to do with is that each amino acid has a certain degree of
11:58 and so what it's doing is it's how to turn it in a specific
12:02 . It's not actually saying I want to be at 80°, it's kind of
12:06 it in a particular direction as opposed the wrong direction. All right.
12:10 again, there's biochemists at this at university and all over the world,
12:16 even at this university who are still to figure this stuff out, so
12:20 don't know everything. Be the first tell you. So, that leads
12:26 the question. All right, let's deal with the protein then.
12:29 , proteins have levels of organization. does that mean? What it means
12:35 we look at a protein, there different ways that we can approach this
12:38 ask the question about functionality. The first level is what you see
12:43 here, it's called the primary Primary structure simply is the sequence of
12:49 acids from the interministerial c terminus, ? It's the letters in the order
12:54 which they appear in each of those represent amino acid. Right?
12:59 this is what this is trying to you something look alright if I'm looking
13:02 this and again, I don't know is the internet. Well I guess
13:04 would be the c terminus since they've it up, it'll be going
13:07 so at this portion of the chain see phenylalanine loosen, Syrian Sistine,
13:12 don't need to know what those It would be like, that would
13:14 the sequence and you can see the begins way over there and it just
13:17 going and going and going and that sequence would be the primary structure.
13:23 what makes each protein unique at its basic fundamental level. Alright, it's
13:29 structure. Primary structure. If you primary, that means there's got to
13:36 something called secondary and in case in case we're gonna be going up to
13:40 levels. Secondary structure are unique structures are derived from the amino acids in
13:50 primary sequence. Alright, so in words, if you were to look
13:53 that protein, you'd see like, look in this little region right
13:57 I have something that looks like a in this region over here, I
14:02 something that looks like a flat plane this region over here, I have
14:05 helix and I have another helix, I have another helix. And so
14:09 of these little structures, the helix these planes are the secondary structures that
14:17 derived from that primary structure. So say derived because it's dependent upon the
14:24 that happens to be there and I'm give you an example that's probably gonna
14:28 any sense to you. But I'm just nod your head and pretend like
14:32 understand what I'm saying if you if don't. Alright, I worked on
14:35 protein called a home mailbox proteins. home box proteins have a shared unique
14:42 structure. It's a DNA binding region other words, is a protein that
14:45 along and binds D. N. . And to bind that DNA that
14:49 this region that is made up of Hipple. Sorry, helix turn
14:55 Okay, so again we don't know it looks like. But you can
14:58 of picture something that kind of does spinny thing and it turns on itself
15:01 doesn't spin anything. Again, every mailbox genes in the body and there
15:06 lots of them have that unique And so it's something that you can
15:11 for in all home box genes. how does it get that sequence because
15:16 shares a common primary sequence in that of the protein. All right,
15:22 , what this does is the reason get these shapes is because what you
15:28 acids are there is what I Right, so if you think of
15:31 amino acid having that variable group that group that sits to the side that
15:36 group and how it interacts with other groups within the protein helps to produce
15:42 secondary structure. Right? So this is something you can conceive if
15:46 have a positively charged amino acid and a negatively charged amino acid
15:51 There's an attraction to them, And they're gonna turn themselves in such
15:55 way. So they're pointing towards each , right? A polar amino acid
16:01 gonna point itself outward. A non amino acid is gonna point point itself
16:07 from where water might be. And these influence secondary structure. So the
16:14 common secondary structures are these two right , I think they thought there was
16:19 be more and then there wasn't. so we have the alpha helix and
16:24 have the baited pleated sheet. Now , I'm not asking you to ask
16:27 what are the amino acids that make up? I mean, you can
16:30 here there are variable groups. But you can see is that there's these
16:35 shapes. So the alpha helix is coil that basically allows this thing to
16:40 this kind of tube like structure. as I mentioned in the example of
16:43 protein I used to work on, allows it to interact with DNA.
16:47 can make it allowed to interact with of different things. Right? And
16:51 I go back, you can see , do you see all the alpha
16:53 is in this one, Do Yeah, it's like coil coil coil
17:00 coil They're all over the place over . You can see I don't have
17:04 as frequently as I have over But look over here, you can
17:07 these kind of arrow looking things that artist has put in. Those arrow
17:11 things are beta sheets. And what beta sheet is. Is this kind
17:14 this flat, like a ribbon type . And you can see how the
17:17 acids have their variable groups going in directions. Kind of create this flat
17:22 and then it kind of turns on and then comes back and interacts with
17:26 . So it creates these flat areas the proteins um that create these unique
17:31 . So in terms of what they , this provides elasticity in the
17:34 proteins. So, think of Alright, you guys are all young
17:38 your skin is still very tight. look at my flabby skin,
17:42 I'm old. My skin hangs It droops, I've lost that bounce
17:49 young skin has. Or as the says the elasticity. Okay, so
17:56 would be an example. That's what see in collagen. Alright,
18:00 beta sheets provides flexibility of globular Globular proteins are the primary proteins and
18:06 basically just describes their shape fibers would like a fiber globular is like a
18:11 of paper just scrunched up and it's globe. All right. And that's
18:17 these are. Sorry, go back . You have to go under the
18:22 to do that. Right? That be a glob glob. This
18:31 What is the name of the It's just the variable group.
18:34 remember when we didn't I ask you to memorize, like show that big
18:37 of amino acids. So it's what thing hangs off to the side that
18:42 each amino acid unique. I'm just to understand. Yes. The r
18:49 for his. Hi. Alright, this is this is a good
18:54 So, it's a chemistry question. , I'm not gonna go deep so
18:57 everyone doesn't get truly bored. I only want a third of the
18:59 to fall asleep or expect, you ? And that's good. Right?
19:04 , notice the position of the czars they are. Right? The hydrogen
19:08 is just a hydrogen bond basically. there's an oxygen that has an extra
19:14 and the proton doesn't have is lacking . So they're interacting because of that
19:19 desire to be next to each But the reason you end up with
19:22 particular shape, this is what's holding in place. Those little lines are
19:26 what's holding it in place. But causing to get in that place is
19:29 sitting out here. So that means amino acid right? There is probably
19:34 polar. And so what it did that that amino acid in such a
19:39 . So that it's pushed away from and more towards the inside of the
19:44 . The ones over here for example be probably polar. In other
19:47 it's being pushed outwards so it can with water and that's why it's kind
19:52 maintaining that particular shape. Alright, , again, the depth here to
19:57 you need to know that you don't to know any of that.
19:59 It's just you can just say the groups influenced the shapes. Right?
20:03 not asking the question of what variable influence which shapes. That's what chemistry
20:08 for. And you get a whole of that. Plus then you get
20:12 chemistry for a whole year if you to do that. And if you're
20:14 , really enjoying it and you can a peek him, you know,
20:18 is fun because there's bumper stickers out that say I survived the camps.
20:22 right. But does that does that your question? The It's which ones
20:27 pointing? So it's the variable group causes the direction when you're pointing.
20:30 then it's kind of being held together that. So, now we've got
20:33 primary structure which is the sequence the influences the little shapes that you find
20:38 the context of the protein. So tertiary structure. The third level is
20:44 whole shape of the whole protein. thing there. The shape of the
20:48 protein. Alright. So here we've primary structure. There's our sequence
20:53 secondary structure are alpha hillsides, beta here would be the tertiary structure.
20:57 is the whole protein itself. within the context of that whole
21:01 you'll have alpha he sees you have sheets, you'll have many of the
21:07 types. And it's how you get total shape of the protein. All
21:12 , so, how do we get ? Well, again, it has
21:15 do where the different amino acids are and how they're causing things to interact
21:20 one another. Things are going to out where things are gonna point
21:23 You're gonna create a whole bunch of types of bonds. We already saw
21:26 example of hydrogen bond. An ionic is simply an attraction between a positive
21:31 negative charge. Alright, we have things. These Vander wal forces.
21:35 , you don't even know these, just kind of point out this is
21:37 a different type of of attraction between molecules. Have you ever seen
21:44 you guys lived in Houston long enough see the gecko. Right, have
21:46 seen a gecko run across a window wonder why or how it does
21:51 It's not suction cups. They don't suction cups. It's actually they have
21:56 structures that allow them to interact with charges in the glass which are
22:02 very small and they have they create der Waals forces that are strong enough
22:05 allow them to pull themselves across, know, what are what are seemingly
22:10 surfaces. It's kind of cool. you have to make the sound when
22:16 make a gecko noise. Alright, all of these different things help to
22:21 it in place. So when we about heat and ph what you're doing
22:26 you're adding an energy to disrupt this this is what causes the unfolding of
22:31 protein. But when you're looking at , oh, there's that shape.
22:36 shape is a function of the secondary that were created by the sequence.
22:41 right. And so that means on outside, the things where you're
22:45 on the outside, that's where the are taking place. Right? And
22:50 those interactions allow for that protein to the stuff that it was built to
23:00 . Not. All proteins have a structure, but there is something called
23:03 structure and quaternary structure simply is when create two or more pollen peptide chains
23:09 get together and the interact not in co violent way, but in a
23:13 that they stay as a group So, this is one of the
23:18 molecules you'll always see whenever they talk coronary uh stuff in any textbook,
23:23 probably going to point to this. is hemoglobin. Alright, hemoglobin is
23:28 polyp peptide. So you can see is a protein, they're a
23:32 Their protein. Their protein. They're held together by these unique chemical
23:38 So they don't just fall apart. , And this structure is responsible for
23:43 oxygen in your blood, specifically inside red blood cells. Alright,
23:48 the fact that you have oxygen. body is because of this molecule right
23:51 . And this is how you deliver to wherever it needs to go in
23:54 body. All right now, not proteins will have this type of level
24:02 organization, but what this little molecule done and said, oh, I'm
24:07 hang out with a couple of my or sisters. And what I'm gonna
24:11 is that allows me to carry more more efficiently and to interact in such
24:16 way that I can release oxygen freely grab on the oxygen better when I'm
24:21 this type of structure. So, basically just a unique organization that some
24:29 use. All right. Some of will have prosthetic groups prosthetic group.
24:34 you can think what is a prosthetic . Like if I if I have
24:37 prosthetic arm, what is it? like it's not a real arm.
24:43 a constructed arm. Right? So not when you see a prosthetic
24:48 when you're talking about proteins, it's a protein. It's something else.
24:53 so with regard to hemoglobin, that yellow thing that looks like a flying
24:58 in there, I guess. I know what it really looks like,
25:01 the artist put in there, That's prosthetic group. And really what this
25:05 is a chemical called a pigment. an organic chemical. And it binds
25:11 auction. Really, really easily has in the middle of it, and
25:14 what is attracted to what the oxygen attracted to. So, this binds
25:18 because of its prosthetic group. All . Now, you don't need to
25:23 what hemoglobin is. I'm not That's and P. Two, but I
25:26 just want to kind of do So, it's an aggregate of two
25:30 more polyps or peptides. Alright. remember peptide has its own tertiary
25:38 So, quaternary structure is a bunch things with tertiary structures that have been
25:42 together to create something bigger. All , now we're going to back up
25:50 little bit. Ask the first Any questions anyone falling asleep yet trying
25:57 hard. Yeah, go ahead. question is how do the folding
26:06 Alright, so, all the folding place first as a function of their
26:10 makeup. Alright. Which we don't about. But what the chaperone molecules
26:15 doing is they're helping the protein fold the proper way. And how does
26:21 do that big question mark? That's where we're gonna leave that.
26:26 so, the chaperones help think about you think of chaperone, what do
26:30 chaperone do? Right chaperoning? The helps the kids not make dumb
26:37 Right. Is that what chaperone does was I was trying to approach it
26:42 a fatherly perspective not from the why you here And interrupting my fund
26:49 Okay. All right. Since that's . Let's take let's take this to
26:56 next thing. All right. What looking at here is something called the
27:00 membrane system. Does this look Yeah. Does it look like all
27:07 things we've already talked about? it starts with the nucleus right from
27:13 nucleus. We see the enterprise particularly the enterprise and particularly we see goldie
27:17 between those two we see some vesicles called transport vesicles. And then on
27:20 other side of the golgi apparatus we a couple of other vesicles that are
27:23 shown. And then we have the the plasma membrane. And so,
27:27 we're really looking at here are structures are from plasma membrane. And remember
27:34 said, starting at the nucleus, same things that make up the plasma
27:38 are making up that nuclear envelope that membrane. And then those things continue
27:44 to make the ectoplasm particular which continue and on and on. All
27:48 So, all of those structures are to each other in in the
27:55 At first structurally they are made from same material. Alright, They have
28:00 functions. But what is ultimately the if you think about what we talked
28:06 the nucleus contains what chroma tin, is DNA which is your genes which
28:13 responsible for containing the instructions for making . Right. So, we're going
28:23 make proteins. Where do we make proteins into plasma critic? Yeah.
28:28 now. We also make it in places but within the context. This
28:31 into place in particular. And then do we do in the Golgi?
28:36 you remember what processing? Yes. post translational modification is the really scary
28:43 work that we use. All So, notice post translations. What
28:47 translations turning things into proteins. And then from post translational modification,
28:53 what we're gonna do is we're gonna those proteins to where they need to
28:58 . So, all these things are to each other in the context of
29:02 do we make proteins go to where need to go in order to do
29:04 things that they're supposed to do. what all this stuff does.
29:09 so, they're interconnected between each other vesicles. The vesicles are these small
29:15 lack of better term bubbles. Of plasma membrane that have a unique
29:21 in them carrying the stuff you need one to the next. Right up
29:26 , I have metabolism and transport when you're dealing with proteins, anything
29:30 they're doing chemically is a chemical Right? So that's metabolism. And
29:36 with regard to all these things, can see protein synthesis, protein,
29:40 making and moving lipids around and then detoxification because we're gonna be dealing with
29:44 license terms again. So, we've these vesicles. These are containers moving
29:50 around to where they need to Alright anybody watched the video that I
29:55 the, did you watch it? you see the connections and the
29:58 Was I right. Was it like Disney structure? You guys see that
30:03 there? Did you watch that? , They look like this,
30:07 And they have these little tiny legs they literally do interact directly with the
30:11 tubules and they carry on their And then the particular video you
30:15 it's like you've got this little tiny and you can see this massive vesicles
30:19 it's carrying on its back and if look carefully at that video and so
30:23 gonna go back down and watch, see there's little tiny things sticking out
30:27 that giant vesicles. These are eventually to be proteins that are gonna be
30:32 into the plasma membrane. If you about that video at the end,
30:35 kind of see this scene where the the vesicles joins up these things kind
30:40 pop up into the surface. Do remember that? Okay. It's not
30:44 all right. I have a real for remembering things in movies, which
30:49 really, really kind of a good and kind of a bad thing at
30:51 same time because I got my brain of a whole bunch of bad
30:56 you know, But I'm really good trivial pursuit. All right. So
31:01 vehicle, the vesicles themselves, they're just floating around inside the cell there
31:05 directed to where they need to go order to provide the function for the
31:09 . Alright, So we said, using these these motor proteins. The
31:13 and the dining is to move things where they need to go in order
31:16 move. You need to use This is going to be a
31:19 And then what we're doing is we're sure that things are going to where
31:24 are good. Now, one of things and I'm gonna talk about this
31:31 , this is incredibly important detail. not it's to extend the idea of
31:37 are going to where they need to until they're needed. Alright,
31:41 there's some extra detail here that I need you to understand. But in
31:45 what happens is when a vehicle gets the plasma membrane, it's not just
31:50 there and it's gonna magically merge with plasma membrane. There's a dock.
31:57 . It's like a boat going to dock. There's literally a place for
32:00 vessel ago. There's proteins in the membrane of the vesicles, and plasma
32:05 in the in the membrane of the membrane that allow these two things to
32:10 . These proteins are called snares. I guarantee you there were probably three
32:15 who sat around and said, what's best acronym we can come up
32:18 That makes it sound like they're interacting each other and they probably came up
32:22 a whole bunch of words and then out words to kind of fit in
32:25 letters to make it an acronym because on snare. I mean really?
32:29 wasn't like, oh, look, , we've got an acronym here,
32:33 ? In essence, what this is you is like, look, here's
32:35 vesicles. What happens is, is transported to where it needs to
32:40 It docks because of these snare proteins then it's held in in close
32:47 All right. Now, the way want you to envision this is an
32:51 kiss. You guys ever see the hitch one person. All right.
32:57 rest of it's on tbs like every weekend. I mean, this
33:01 it's easy and hitches describing to kevin , I can't remember. Kevin James
33:07 name is how to kiss after the . All right. Said you walk
33:13 girlfriend up to the girl up to door and she's gonna be sitting there
33:17 you cues that. It's time for kiss and you're sitting there. She's
33:21 rattle her keys, she's gonna fumble . She's gonna do stuff. You
33:25 go in for the kiss because that not your you don't have permission to
33:29 that. You have to let her the choice. So what are you
33:32 to do? You remember what he ? Go, you go 90
33:35 The guy is supposed to go in and he sits there at giving her
33:40 10% to make that decision, And it's a very funny scene because
33:46 Smith goes in 90. And then James goes the other 10 and he
33:51 expecting that. It was very That's the 90 10. And then
33:56 what you're seeing right there. The has come up. It hasn't quite
34:01 with the membrane yet. It's being in place. And the reason is
34:05 held in places, because now it's for a signal to say when can
34:09 release my contents? All right. , when you're thinking about what we're
34:14 see this, when we talk about and we talk about neuron, we're
34:18 ask the question of like, here's chemical signals that are being released.
34:21 do we know when it's released? because everything is already in position,
34:25 to go. All you need is sort of signal that says,
34:29 time. It's okay to merge the together. It's not like,
34:33 I've got to drag this thing over then do all this unique stuff.
34:36 already like just flip the switch and , everything is released. And that's
34:41 everything is very very quick. That's your brain works the way it
34:43 That's why your muscles move very, quickly in response to your thinking,
34:47 right, now, you're going to this a lot. It's dependent upon
34:51 when you see the word calcium. think that is a signal to cause
34:56 to happen. It's like the magic dust of the self. All
35:01 This is a picture for you not memorize at all. All right.
35:05 I want to do is I just to show this to you to show
35:07 It's not just two proteins. There's whole bunch of stuff going on.
35:11 if you want to explore this, say okay, here it is.
35:14 . You can see all the different that are there. These are proteins
35:17 the plasma membrane. Then this is docking. And look at what it
35:20 . It brings everything into close And then when calcium comes in,
35:25 when we actually get the merging. , it's just a more detailed picture
35:29 what I just described. So, you're interested in seeing what the details
35:33 of look like, you can look something like this. That's all It's
35:37 . I will not ask you a question about this on the exam.
35:44 , a vesicles moves to where it to go. Alright, there are
35:49 places where it can go. All . The first place is that a
35:54 vehicle can carry things. Right? , inside. So, that's what
35:58 little dots represent. That's what we looking at over here. These little
36:01 dots. It's carrying materials to be into the external environment and so that
36:07 then transported up to the plasma membrane with that membrane and opens up.
36:12 , you can presume that the signal it to do that. And now
36:15 materials have been released from the external . So the way you can think
36:19 this is that the stuff inside the cole is equivalent to being the materials
36:24 . So when you merge it basically up this way, so the inside
36:29 equivalent to pointing outside of the That makes sense, sort of.
36:35 me go back to this picture and see if I can I'm gonna try
36:37 draw on the picture so that you see have I don't remember which tool
36:43 using here. Alright, so I'm draw it this way. So,
36:51 I am thinking of inside versus if I am a There it
37:01 So if I am pointing this that is the same is pointing this
37:09 . Okay, so you can see and I'm pointing. You see how
37:13 still pointing. Like that direction. you see that? Alright, so
37:19 inside of a vehicle is the same as the outside of a cell,
37:23 what we're trying to get at. , so when I'm dumping things out
37:29 the external environment, I'm really already the external environment, I'm just sequester
37:34 Now I'm joining up with the membrane , I'm not sequestered. That's number
37:38 that's secreted the second is moving things the plasma membrane. So you can
37:43 here this is a receptor that is to be inserted into the surface of
37:48 plasma membrane. Notice which direction it's . It's pointing into the vesicles when
37:53 thing merges. Just like we saw it does is that now is pointing
37:58 . Alright. So this is how get proteins planted into the membrane.
38:06 ? Those trans membrane proteins that we earlier on last week. And then
38:12 other type is well, you can things like license zones. So they
38:16 a whole bunch of enzymes in there that license um now plays that role
38:21 digestive system for the self. that's not what it is. It
38:26 acts like that. All right. , I think I have this slide
38:30 just in case you're studying along and like, oh crap. I don't
38:33 the license zone is I don't want go flipping back to the net.
38:36 lecture. This slide is the exact one. Right? It's just with
38:40 prettier picture. And so it shows what type of things that a licensed
38:43 eat. Things that I bring into cell. Things that I you
38:47 like I can bring in individual particles through a particular transport I can bring
38:52 large things like a bacterium or even I have a damaged organ. All
38:56 are different things that I can break with the license. Um All
39:01 But same thing as the other slide one other biochemical um complex that I
39:10 wanted to mention here and then we're to move into that second part of
39:14 lecture I described. This is the zone. Um proteus zone. It
39:20 another type of digestive organ. L job is to act kind of like
39:24 garbage disposal when you want to get of proteins that you no longer
39:28 And so what happens is you have either damaged protein or protein that has
39:33 its job. You're no longer it's longer needed for the function of the
39:37 . Also incorrectly stuff. And what does first up is that the cell
39:41 what it doesn't mean. So it it, it gives it a tag
39:45 says you need to be destroyed. kind of one of the important things
39:49 knowing what you want to keep and you don't want to keep.
39:52 So you kind of mark things as go along. And so it's marked
39:56 a different type of with this it's called ubiquity in And again,
40:00 you try to figure out what does mean? Ubiquitous, it's a protein
40:04 that's everywhere. So that's why they it ubiquity. And then they discovered
40:07 it did and then what happens is you get that marker then that is
40:12 cause that protein to be transported to proteus, right? This protein,
40:18 . And then it just basically just it up. It's like you know
40:22 a wood chipper, you know, a branch in a wood chipper and
40:25 you end up with a bunch of acids. What can you do with
40:28 bunch of amino acids? Put them together and make a new protein.
40:33 , you basically are recycling these monomers do the things that the cell
40:38 All right. So, this is one of the ways the cell ensures
40:42 it's doing. It's right. Job by getting rid of the stuff that
40:45 need and recycling those amino acids to the things that it does need.
40:51 right. All right. This is part I promised would help you fall
41:00 . So, if you're ever having sleeping at night, you go to
41:04 section of the book and just start If you're not by the third
41:09 maybe you need some melatonin and then reading. Alright. And really what
41:16 doing here is we're dealing with the . All right. So, I
41:18 you to picture yourself for a moment I want you to like this
41:21 Right. And you can see there's plasma membrane and that plasma membrane separates
41:25 outside from the inside. Now, a term we use for the movement
41:30 materials in any sort of environment. ? So, if you look around
41:34 room, you can see that students been dispersed roughly equally about the
41:40 Would you agree with that? I , there's there's a tendency in a
41:44 for more students to move a little forward. Right? But generally
41:48 if you look around the room, can see that that you kind of
41:51 in and sit down, you're okay, I've got my space and
41:55 will sit next and you're like, a second, there's a whole
41:57 you know, can't you disperse yourself else you have ever done that?
42:03 , Okay, so this is kind what is called diffusion. I'll give
42:07 another example is real simple. You drink iced tea here? Yes.
42:12 . Okay. All right. If want to sweeten my tea, I'm
42:16 take a sugar packet or if you to use an artificial sweetener, that's
42:21 . And if you dump it what's that sugar gonna do with regular
42:26 ? Not not hot tea, but regular iced tea. What's it going
42:28 do? It's gonna go right to bottom. Alright, so that's kind
42:32 what's going on here, grandkids, off to one side. Now,
42:36 I were to take a sip of tea with that sugar sitting on the
42:39 with that TB sweet would be bitter and do as you are going to
42:45 it a little bit of energy right the process of stirring so that the
42:51 will dissolve and equally disperse itself throughout entire a cup or glass. Now
43:01 live in south. So you should some of you should know the answer
43:05 this. I presume many of you've here in Houston long enough to know
43:08 . How do you make sweet People looking at me like all
43:14 you're gonna live here in the You better learn how to do this
43:18 it's a requirement, right? You tea when you're making it. How
43:22 you make tea? That's the first . You probably know. How do
43:24 make tea? Right, take And what do you do, boil
43:31 ? And then you take tea And if you don't use tea
43:34 you can use the T. I remember what they're called, like the
43:38 . Ball or something, but But what you're gonna do is you're
43:41 to steep the tea alright? And it's in the bag, so you
43:45 boiling water, you put tea in bag, you got your T.
43:48 then to drink it, then you're cool it down. But if you
43:51 to make sweet tea, what you is you take sugar and you put
43:54 directly into that hot T. You made what happens to that sugar?
44:01 dissolves right away. Now when we dissolve, what it means is you're
44:05 big crystals and you're causing the molecules those sugars to disperse and diffuse like
44:12 . In other words, the energy already in the system because there's a
44:16 of heat there. And so that for diffusion to take place. You
44:20 learned some chemistry today. Alright. , the fusion has two things that
44:26 dependent upon. Alright. And this in any environment. So, we're
44:30 t as an example. So, an open environment. If I put
44:33 down in the fatigue goes down, of it kind of dissolves, this
44:37 going down, but most of it down to the bottom. And so
44:40 we have a concentration grading, We lots of sugar at the bottom,
44:44 little sugar within the rest of the . And so in order to get
44:48 , I have to add an energy this case I'm gonna stir which is
44:52 kinetic for me, I'm moving the molecules around, but I'm also adding
44:56 energy that causes the molecules to separate themselves so that they equally disperse.
45:02 right. So, the fusion is upon those two things. The steepness
45:07 a gradient. The gradient is just saying, where is there more and
45:11 is there less? All right. this room, there is a gradient
45:14 height, it's steeper back there than is or it's high over there.
45:18 not high there. So, the for the room is like this
45:22 where are there people? There's a bit more people on the front than
45:25 is in the back. So, you're looking in terms of the population
45:29 , it's heavy in the front and in the back. All right
45:36 as I mentioned is what reflects kinetic . Alright, It's how much energy
45:42 in the system. The higher the , the higher the molecules are going
45:46 start moving around. They take that they start shaking and they start running
45:50 each other and that causes them to off each other and spread out.
45:54 ? It's like the mosh pit of . Do you guys know what bosch
45:58 is? Okay, just making I mean, you guys are like
46:01 safety generation. So it's you're close my age. I mean, I
46:07 not my age because I'm old. see see the gray, right?
46:12 know, but a mosh pit, know, is when you get in
46:15 and you're just going to start elbowing maybe punch a little bit. Maybe
46:21 people you don't like. So that occurs. Now diffusion occurs everywhere.
46:31 , diffusion refers to moving molecules from area of high concentration to an area
46:34 low concentration. So simple diffusion is that movement of a non polar or
46:42 soluble assistance across the lipid bi So, if you can think of
46:45 room and think of the walls of lipid, right? If I have
46:50 that likes lipids, it can pass the wall just fine. There's nothing
46:55 it. So basically you can think it like this way radiation would be
46:59 example of something that's not impeded by wall. Would you agree with
47:02 So, I can put lots of in the room and then it would
47:06 to an area of lower radiation which be outside as an example.
47:10 So things would move just fine. you do not have to have anything
47:15 place. It will just move in direction where there's less of the thing
47:20 you're looking at when you're dealing with diffusion. All right, can't regulate
47:25 . It's all dependent upon the concentration . And what everything is doing is
47:29 trying to move to a balance to equilibrium on either side of whatever it
47:34 that you're looking at. So, in the glass, it's like I'm
47:37 to equal liberate the diffusion of the so that everywhere all those molecules are
47:44 spaced out. When I'm looking across membrane. I'm asking how much is
47:48 on this side of the membrane versus side. I'm trying to create balance
47:51 either side of the membrane. That's the chemistry is trying to do,
47:57 diffusion refers to the presence of some of transport protein to allow something that
48:04 isn't allowed to go through that So, something that is not lipid
48:10 , something that is polar. for example, you have mass.
48:15 ? And these walls have mass and two masses are incongruent with each
48:20 If you try to go through the , you'll find out very quickly that
48:23 wall will not allow you to do . So we need to have some
48:28 to get through the wall. What do we have? We have
48:34 Alright, cells have doors. All . We have special names for the
48:39 . We have channels. Or we carriers. Alright. And the names
48:44 meaning a channel is literally a path the wall. In other words,
48:50 opens to both sides and it creates passageway filled with fluid that allows things
48:55 move back and forth and you're always to move in the direction of the
49:00 concentration gradient. Right? So if have lots of stuff inside the cell
49:04 I have a channel for the lots stuff, then there's lots of stuff
49:07 going to move out of the cell the area of lower stuff. Whatever
49:12 happens to be. All right, bind to something very specific. There's
49:19 attraction that allows a carry to bind kind of like an enzyme binding to
49:24 substrate grabbing that material and then once grabs that substance it changes its shape
49:31 moves it to the other side to this. Have you ever seen a
49:37 door at a hotel or an Right. Those are those really cool
49:42 . You kind of go in there moving usually and you have to have
49:46 luggage and you kind of get in and then you do this with it
49:49 he goes around and then you get the other side with carriers. A
49:53 is never open to both sides It's kind of like one of those
49:57 is never open to both sides. go into your little slot and you
50:00 to wait until it gets to the side before you can get out.
50:05 kind of how carriers work. You see here, here's an example of
50:08 , I'm open on this side. this comes in, it binds and
50:11 it opens on that side but closes that side. So the molecule can
50:14 go in that particular direction. carriers were dealing with facilitated diffusion carriers
50:21 again moving things from an area of concentration to an area of low
50:24 So over here they're trying to yep, here we have a high
50:28 down here, below. So in particular case we're saying, look
50:32 we have high, so we're trying move in this direction, but there's
50:37 types of carrier media transport is not moving from areas of high to
50:42 We use carrier media transport to also things in the direction they don't want
50:47 go. Alright, And this would the form of what is called active
50:54 , which is on the next All right, now, what's sad
50:58 that? Oh, no, it's it's correct. All right. So
51:00 , what we're gonna do is when dealing with active transport. The first
51:04 you can see here active and that that something requires right to be
51:11 You need to be energetic. And there's two different types of what's
51:15 primary and secondary. We're gonna break down in just a little bit
51:18 But in essence, what you're saying I need to have some sort of
51:21 to move things from an area of concentration to an area of high
51:26 To put this in perspective or give a little example, think about a
51:29 on the floor and a shelf. does the book want to be?
51:35 wants to be on the shelf, ? But in order to get it
51:38 the shelf, you have to apply to get it there right? Because
51:42 natural inclination gravity pulls on the book wants to bring it to the
51:47 Alright, So, you putting the on the shelf requires energy. And
51:52 kind of what's going on here is already in a position where the molecule
51:56 to be. It doesn't want to up here, but you want it
51:59 there. You don't want it inside cell. So you have to add
52:04 to allow it to be picked up move to the other side where it
52:07 want to go. Typically, this what we refer to as a
52:12 right? I have to pump things a direction. If you have water
52:16 the boat, you have to use pump to pump the water out.
52:19 gets in the boat. You don't it in the boat. You want
52:21 out of nothing. But there's less in the boat than there is outside
52:24 boat. Water wants to go into boat, but you don't want it
52:27 . It makes sense. You never boats. That's okay. Well,
52:32 see this. Alright, sorry, or primary and secondary primary is when
52:42 doing this type of moving things in direction they don't want to go.
52:45 I'm using energy directly. Alright, other words, in a primary system
52:52 will come along and bind to the in the energy being transferred to the
52:59 allows you to then move that All right, so you can think
53:04 like it's directly applying energy to the . Secondary active transport is a function
53:12 or the result of primary active Alright, I'm gonna try to use
53:16 example here. We're going to see real examples in a couple of
53:20 but I'm gonna try to do this you can visualize this. Think of
53:23 closet. Think of 1000 ping pong . Alright, I'm opening the door
53:29 I have to put a ping pong , you know, the first couple
53:30 ping pong balls is not a but after a while every time I
53:33 the closet door. Where do the pong balls want to do? They
53:35 to come out. So it's like have to provide, you know,
53:39 extra energy to get that ping pong into the closet, right? But
53:45 I have stored up energy with regard the ping pong balls. If I
53:48 up the closet door, ping pong are gonna come out there, moving
53:51 the direction they want to move. the stored energy is now there to
53:58 particular types of movement. That's what is. Alright, It's using stored
54:04 energy to allow movement of molecules. , there's not gonna be a good
54:10 example, but if I could use ping pong balls to turn something like
54:14 crank as they leave to allow something to happen. You know, I
54:19 know too. I don't know. not gonna come with a good example
54:22 the top of my head. But idea is the movement of the ping
54:25 balls out of the closet. That of that that movement is then used
54:30 do something else. That would be secondary active transport. I'm gonna show
54:35 examples and hopefully it will make more when we're using real molecules. All
54:40 , But primary is direct. I'm energy directly. Secondary's I'm using energy
54:46 primary active transport and move something. so now I have stored energy that
54:50 be used Now diffusion. This this this stuff was discovered like in the
55:00 1700s, the guy that discovered his name was thick, I can't remember
55:04 first name. And he did all stuff in the 1700s with tubes that
55:09 as big as this room. And figured all this stuff out, which
55:12 really kind of cool you know? this is not like modern day.
55:16 figured this stuff out. Some guy a tube filled with fluid figured this
55:20 out and basically says diffusion depend upon couple of things. First off,
55:24 size of the salute. Eyes Big things have a hard time moving
55:31 each other. Right? I'm gonna the example of my kids. All
55:34 , take them to a sporting You can imagine everything is all
55:38 People, you know, crowds are up. Me moving through the crowd
55:42 effort. Right? You think about sporting event where it's crowded? It
55:45 take effort to move through the Yeah, my kids are half my
55:49 . All right. They can run your legs, right? So if
55:53 let go of their hands, they're bunch of molecules that just zip between
55:57 , right? And they're gone. matters. Big objects move slowly.
56:01 objects move fast. So the smaller object, the easier the rate of
56:05 or the faster the rate of diffusion easy to kind of remember,
56:10 membrane, thickness. The thicker the , the harder it is to get
56:14 . All right. And that that be too difficult if I have
56:17 You know, it's just think of as how far I have to travel
56:20 I have to travel through something and takes time to go through it.
56:24 more of it I have to travel the longer it's gonna take. All
56:27 . So, that has an effect surface area. All right. Um
56:34 a door right here. How many come through that door at the same
56:36 , do you think? Two? about dr wayne size people? Do
56:44 think two of me could fit through ? That would be real impressive.
56:47 think it'd be more like three students they were to It would be kind
56:49 like we just go in there and up and it's kind of Yeah,
56:53 , so, too But you could three through there. Right? How
56:56 I want to get three people through at the same time, what do
56:58 need? The door? We need make it wider. Right, have
57:02 increase its surface area. All So, in other words, the
57:06 area in which I'm having movement. ? The more things that are things
57:12 passing through, the bigger that surface , the greater the rate of
57:16 Alright, so, you can see here we have the doors over
57:20 The doors back there. The doors and the doors are there, the
57:22 at which you can get out is function of those doors. If I
57:25 to increase the surface area of diffusion students into this. What I do
57:29 I added more doors. All magnitude of concentration. We've already
57:35 The higher the concentration gradient, the the rate of movement to visualize
57:40 I want you to think about skateboarding Houston. Alright. Houston is a
57:44 flat city. Would you all agree that? Yeah, it's more or
57:47 flat. If you get on a , you're gonna be moving anywhere?
57:51 , that's why we have motors on skateboards and scooters, right? You
57:54 on a skateboard on a flat piece property, you're not gonna move unless
57:59 put in energy. Alright. I up in El paso. El
58:03 There's a big giant mountain in the . I grew up on a hill
58:06 was this steep. It was You learned how to do all sorts
58:09 things to hurt your body. All . If I got on a skateboard
58:13 a hill, this steep, am gonna move? Yeah, yeah.
58:17 , the steeper the gradient, the I'm gonna go. Right,
58:20 if I get on a hill that's , I'm just gonna kind of roll
58:23 I get on the hill that this , I'm gonna go faster. If
58:25 get on the hill, this death is probably going to occur steepness
58:31 . So magnitude is the how big steepness or that great. We mentioned
58:38 an energy temperatures energy. Its kinetic . The higher the temperature, the
58:42 the rate of diffusion lapsed, the of the solution basically is how much
58:47 do I have to run into viscosity dependent upon the number of items in
58:52 solution. Alright, so if you have water, you're only dealing with
58:56 molecules, but if you add in and you add in other types of
59:00 then it's gonna get thicker and denser things are gonna be running into each
59:04 and so it's harder for things to in a viscous fluid. So when
59:11 deal with diffusion there's a couple of you're going to hear, you can
59:14 the term flux flux is just the of diffusion across the membrane. So
59:18 you're dealing with an eye on your what is it, what is its
59:21 ? You're asking? How fast did get from this side of that
59:25 Net flux is the difference between, know, directional movement. Alright,
59:29 here what we have is we have whole bunch of red balls or red
59:33 , a whole bunch of blue Where do the red molecules want to
59:37 ? They want to diffuse until there's . So I have three and three
59:40 either side. See that's the we'll get to the equilibrium in just
59:44 moment. Alright, net flux what is the rate for these to
59:48 that way? Plus the blue ones go the opposite direction. So basically
59:53 moving in the opposite direction towards So the netflix is the difference between
60:00 going this way versus that way. , equilibrium is when uh you basically
60:06 don't see any net flux anymore. . That doesn't mean molecules aren't
60:12 It just means for every molecule that this way, there's a molecule moving
60:15 way. And so you don't see difference any longer equilibrium has occurred.
60:21 there's no movement, That's a sign death in chemistry. All right,
60:26 a bad thing. So there's always occurring. It's just there's no net
60:31 , that's equilibrium. And then this bulk flows flu thing. You'll see
60:36 couple of times a little later in and P. Particularly in the circulatory
60:40 as well as with the respiratory bulk flow refers to the movement of
60:47 substances within a salute. Excuse Within a solution, not install
60:52 Alright, so the way you can about this is in about how much
60:57 do we have um In about 20 we're gonna have people coming into this
61:03 and we're gonna have people moving out this room and some people are going
61:05 stay in this room and then there's be people moving around all over campus
61:09 to all the different places. And of asking the question of where
61:13 for example, all the women you're asking where are all the students
61:17 ? And so you can look at net flow, Right. People are
61:21 moving onto campus to go to classes leaving campus and in the afternoon,
61:28 people are leaving campus that are probably onto campus. Right. That would
61:33 an example of bulk flow. With to your systems. Think about breathing
61:38 you breathe in. What did I breathe into my into my body?
61:43 hear a lot of oxygen, but focusing on a single thing. What
61:46 I actually breathing in air? What is air made up of nitrogen
61:54 oxygen? And then carbon dioxide and about a billion other molecules that we
61:59 even bother to think about. All , now, when I'm breathing
62:03 what does my body want? your answer is appropriate oxygen,
62:07 But I'm still breathing in carbon dioxide I breathe in air. Right?
62:11 bulk flow refers to that net flow air into my lungs, right?
62:18 what I'm doing is I'm focusing in one of those chemicals, one of
62:25 gasses. So bulk flow is all it, even though I only want
62:29 one. All right. So, a non member of the entire solution
62:33 an area of high pressure to an of low pressure Yeah, membrane permeability
62:43 we talk about a membrane because this where all the action is taking
62:47 Um with regard to inside versus we ask the question about what's membrane
62:52 if we're moving things on either you know, we're trying to get
62:56 from one side or the other. have to understand the condition of the
62:59 . The membrane is said to be if it allows the passage of a
63:03 substance. So, for example, membranes are permeable to our gasses.
63:07 right. It's said to be impermeable it disallows passage of a given
63:12 So, for example, are membranes impermeable to charge particles. All
63:19 And that's a result of the characteristics those fossil lipids that we mentioned
63:25 Now, if you think about it , membranes are not permissible to just
63:29 couple of substances. I mean, permissible to a whole bunch of different
63:32 of substances and it's impermeable to a bunch of other different types of
63:36 So, it has these characteristics that shared, Right? In other
63:40 it's neither permeable or impermeable. It selective permeability. That's what that phrase
63:48 . It means it's permissible to some . It's impermeable to other things.
63:52 that is why it's choosing what goes and forth. The selective permeability.
63:58 right. So, you'll hear that when it comes to this communication.
64:06 right. How many guys have taken class where you've learned osmosis.
64:13 How many of you guys who just your hands can tell me what osmosis
64:17 like, Oh, I love Thank you. And you've got one
64:21 back their most people. They put hands right back down again because they
64:24 something for a test and then they're , I don't really get it.
64:27 didn't really understand osmosis even like three four years into grad school, you
64:31 , because it was just like I'll memorize the book definition and hopefully
64:35 one will ever asked me ever But you have a really good
64:40 So in chemistry, they confuse us this is one of the reasons I
64:44 of tease the chemists, right? not because they're trying to be
64:47 It's just that they don't know how be easy, right? And so
64:52 they'll say is like ah well, is the movement of water from an
64:57 of high solid or from an area low salt concentration area of high solute
65:02 and all of a sudden now your is kind of doing backflips trying to
65:05 what all those terms mean. All . But I was mostly in terms
65:10 its simple definition. If you walk of here understanding this, we're we're
65:14 water is simply that our was most simply the diffusion of water.
65:18 if we understand what diffusion is diffusion moving of solitude from an area of
65:21 concentration on a very low concentration, osmosis is moving water from high water
65:26 of high low water or too low concentration. So if are you with
65:31 ? All right. The thing is just going to use this picture up
65:36 . So, what we have up is we have these little red
65:42 Let's just I think they're going to particles but we're gonna use it for
65:47 the moment for water. All If you're thinking of this membrane right
65:52 being permissible to just water. And you look at this side, would
65:56 say that there are these two areas in equilibrium? Just looking at the
66:00 dots? No. Alright. what we want is we want equilibrium
66:06 these two areas. That's really what saying. Alright, so water is
66:11 you think of this as being right, that whole area is being
66:14 in that whole area is being The water in this area Is making
66:20 a percentage of the 100% and the in this area. And I kind
66:25 confused because I'm saying the red is . The really it's the blue that's
66:30 . The water in this area is percent than over there. Do you
66:34 with that? So, in other , if each of these sides,
66:37 this is 100% and that's 100%. water in here makes up a greater
66:42 than over there. Right. And want equilibrium. So, what do
66:46 do? Well, water is going try to create equilibrium by moving from
66:49 area where there's more water to where less water. Okay. So which
66:54 is water gonna go? This has water and that has less water.
66:56 way is the water gonna go? gonna go this way right? Until
67:00 equilibrium, so it's going to keep in this direction, so the
67:04 the volume in here increases relative to other area, and water is going
67:08 keep moving until equilibrium is met. you're saying, wait a second,
67:13 doesn't always make sense to me. a second. What happens when the
67:18 over here? So great, that I can't move anymore water?
67:25 , I gotta back up because there's story I'd like to tell with
67:28 You guys know how smart car You've seen a smart car,
67:33 How many people, When I asked in the back here, how many
67:36 can fit in a smart car, to you? Sure. Well,
67:43 you three of your buddies want to on a trip in your smart
67:46 you're gonna, are you gonna, you fit them all in? So
67:48 , you can get probably three in . Do you think you can get
67:51 ? I didn't ask comfortably. I'm could you get four people in a
67:54 car? Sure. How about five . How about six now we're starting
68:00 get really, really crowded. Do see we can keep there's a finite
68:04 inside that car, Right? I keep shoving people in that car.
68:07 gonna be a point where I'm gonna it. I'm just gonna make it
68:10 . Let's say it's the ninth I take that ninth person. I
68:13 them in the driver, the passenger . What's gonna happen on the driver's
68:17 ? Someone's gonna pop out, aren't ? Right. And that's kind of
68:21 you're dealing with the osmosis, you this issue as well. Water is
68:24 to keep moving, trying to create gonna be a point where the volume
68:30 water, the pressure that you're, you're putting into that system on this
68:34 becomes so great that the next water that goes in, It says uh
68:39 it kicks out another water molecule that out the other side. Alright,
68:43 osmosis has some characteristics. First, that water is moving down its concentration
68:48 , chemists say it's water is moving salute, and that's the same
68:52 It's just it's throwing in a different to make it confusing for you.
68:56 , if you can always think water moving from high areas of water,
69:00 areas of water concentration, you're always to get it right? You just
69:03 to ask the question. Where is is where is the more water?
69:07 , I always ask that question. move through the structures called aqua
69:11 They don't need aqua porn. But makes it easier. Aqua porn is
69:14 a water channel. Water moves through . All right. And so you
69:18 also pass through the fossil lipids. one of the unique characteristics of
69:22 even though plasma membranes are supposed to polar molecules like water. Water for
69:27 reason, can pass through the possibility just fine. Right? Should they
69:32 to by osmosis? All right. , that pressure that all fluids have
69:39 hydrostatic pressure. Alright, I'm gonna his bottle for a second.
69:42 I'm gonna steal your bottle because Because can see the water. C do
69:45 guys see the water in the Why is the water still in the
69:50 ? Grab it, grab it and it out. Why is the water
69:52 the bottle? This is not a question, because this has force,
69:59 ? Water has a hydrostatic pressure. water is desperately trying to get out
70:03 that bottle. See, can you it? Look It's trying so hard
70:05 get out. All right. You see it. Imagine if this water
70:11 was not plastic, but it was . Where would the water go down
70:16 out and everywhere. Right. what we have is we have a
70:19 inside here that's pushing outward against the in all directions and trying to
70:24 The water is trying to escape. hydrostatic pressure so far. You're with
70:28 . All fluids have this. The in here trying to pursue its water
70:33 be whiskey. I don't know. right. All the water in here
70:37 trying to escape as well. I can create pressure on this and
70:41 can drive and create greater pressure on inside, couldn't I? My squeeze
70:45 hard enough. Water could go popping the top. I'm not gonna do
70:49 . Right? So everything. So it has a hydrostatic pressure.
70:55 , when we see the word osmotic , what it's describing is the hydrostatic
71:00 . When you reach that point where pressure pushing in is equal to the
71:05 pushing out. Right? So, that person went into that little tiny
71:10 car, that last person and it that other person come out, you
71:14 that point where the pressure on the is equal to the pressure on the
71:17 , automatic pressure is simply the opposing . The hydrostatic pressure in here becomes
71:22 enough. So that when that next comes in it kicks a molecule
71:26 So it's just a hydrostatic pressure. definition is simply when the opposing pressure
71:32 to completely stop osmosis. What's The diffusion of water down its
71:38 So, when the hydrostatic pressure here so great that this no longer allows
71:42 to move in. You've reached osmotic . There you go. Thank
71:50 All right. So, we have conditions when it comes to osmosis.
71:56 , your cells are trying to deal these different types of pressures. It
72:01 molecules trying to move back and forth the membrane. We see this term
72:07 . And if you're planning on going the field of nursing, this becomes
72:09 very very valuable term. Alright. Tennis city. Tennis city is simply
72:15 ability of a solution to cause a to gain or lose water.
72:20 You are in working in the emergency , Someone comes in dehydrated. The
72:25 dehydration means they are lacking with water their bodies. So your immediate
72:31 have you never been trained is oh will give them water. All
72:35 Well, what happens is if you someone pure water, what you're doing
72:39 you're affecting their tennis Itty. And water is looking for the area of
72:45 water concentration based on what we just , right? So if you're
72:49 your cells are lacking water. And water will go rushing into a cell
72:55 try to reach equilibrium and it will the cell to swell and then
73:00 That's not good. Right? So you have someone who's dehydrated to the
73:04 where they need to go to the room, what do you give them
73:07 know you want to work in the room? I. V. Fluids
73:11 is do you know what's in the ? I'm hearing good answers of water
73:18 sugars. So basically it's a fluid water that has solid in it.
73:24 what you've done instead of having lots water and very little water, you
73:28 more water. And so the rate movement into the cell, the
73:33 the osmosis is slower cells don't pop quickly. You don't affect the Tennis
73:38 quite as badly or you don't cause to pop. All right. So
73:44 you'll hear is you'll hear terms like hippo tonic, isotonic hyper tonic.
73:49 the prefixes easy hypo is less. the same hyper is more. You
73:53 have probably learned that at some point your life, right? If you
73:56 you now know the prefixes. The tonic portion refers to solution.
74:03 right, Or to the salute in solution. So, if you're hip
74:07 tonic, what you're saying is the has less salute than the fluid that
74:13 the stuff that's inside the cell. , so it's lower solute concentrations.
74:19 you go. Water moves from inside cell. So I should be over
74:24 inside the cell to our water moves the cell, causing the cells as
74:30 because there's a silence of water basically in and goes to where there is
74:34 water and causes cells to pop or . That's usually the bad thing.
74:39 right. So it has a higher concentration. So what an ivy is
74:43 typically hippo tonic but it's basically It's closer to an isotonic solution which
74:49 why we give it isotonic means you equal. Do you ever anyone here
74:53 Visine? Ever. You know what is The eye droplets. It's a
75:00 saline solution. It matches the exact of your eyes. It's not the
75:06 same stuff. Same tennis city. it moisturizes, moisturizes your eyes without
75:13 water out or putting too much water . So equal parts when you're dealing
75:19 a hyper tonic solution, hypersonic solution more salt, more salutes. And
75:24 that means there's less water. So is gonna be drawn out of the
75:27 to kind of try to create Alright, so you'll hear those
75:33 I've given him an isotonic or hyper or a hi platonic solution. And
75:37 it's referring to is this this stuff we talked about with regard to osmolarity
75:44 regard to the cell itself. I'm a lot slower that there's still fewer
75:52 and I got so much slower on stuff and I don't know why um
76:04 going to stop because if I go the next if I talk about
76:07 I'm just breaking up right in the of something. It's weird. All
76:11 . I will talk faster on I promise. How many people did
76:15 make fall asleep? Anyone almost? . I tried I really did.
76:21 . So when we come back we'll back and we're gonna deal with these
76:24 and we're gonna talk about how cells to each other. All right.
76:27 good.
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