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BIOL 2301 Human Anatomy & Physiology I - BIOL2301_lecture05_0905
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00:03 There we go and now we're now . Ok? Um Just a couple
00:07 things. I got a couple of going, hey, how you
00:09 Uh How are you doing? That's you uh say, hey, um
00:12 can't find the CASA link. I know how to log in or
00:15 you know, I'm using my old and they haven't updated my, my
00:18 yet. Everything for CASA is now canvas. So there should be a
00:23 on the left hand menu. Just Casa click that and that will take
00:27 to your sign ups for your classes . OK. So if you've been
00:31 the old Casa link and you've been problems getting to sign up for your
00:36 , that's why they just, that, that website no longer works
00:40 Today, what we're gonna do and just in case you don't
00:43 we have a test from Thursday, not Thursday, not Tuesday a week
00:50 this upcoming Thursday. So what we're do today, um We are going
00:56 be kind of trying to finish out little bit with the organelles of the
01:01 . We're going to be looking at translation first. And then we're going
01:05 kind of finish up with the And we're going to look at how
01:07 move back and forth across the membrane kind of how we should be finishing
01:13 looking at some of these mechanisms. today is a real physiology, heavy
01:18 . So a lot of this is , I've got to kind of grind
01:20 and think about what it is. actually looking at here what's what the
01:25 is actually doing. And so with , we're going to just kind of
01:29 where we left off. And, what we were trying to describe here
01:32 how do we make RNA, how we make M and the message that
01:37 used as the blueprint for the proteins we're going to be making. And
01:42 starting point here with that was what a gene and a gene simply is
01:47 strand of DNA. So it's part DNA. So you have 23 pairs
01:52 chromosomes amongst those 23 pairs of you have about 30,000 genes. And
01:58 you were to look at a gene say, let me see if I
02:00 identify it. The gene includes a point and then a whole bunch of
02:05 and then an ending point. But that, you're going to have these
02:09 that only for the gene or the that you're looking at and they
02:14 interrupting sequences and we call those exxons introns. And the intron is the
02:19 sequence. That's how I remember It's the one that starts with an
02:22 that you don't use. And for and years and years we thought it
02:26 junk DNA. It's not junk but we're not going to go into
02:29 we have introns. So you have portions that you're going to need and
02:33 that you don't need. And so little car tune that we were looking
02:36 here at the bottom kind of shows what a gene would be represented
02:40 And so you can see there's, these regions that are binding regions that
02:44 not going to worry about. But that arrow is, it's saying this
02:47 the reading frame. This is what gene starts at and then it reads
02:52 where through the green block, the blocks, the little triangle looking things
02:56 the way down to the stop sign thing. All those stop signs,
03:00 guess are eight sided, not But the idea is all that would
03:04 the gene. And then that stuff stuff that we don't need to make
03:09 MRN A. And so what has happen is even though we transcribe that
03:14 thing, we still have to Now, I'm going to go into
03:17 detail than you're going to need. right, you just need to know
03:21 process. But what I want, to understand is so this is kind
03:24 what you're looking at. You can here, here's my intron Exxon
03:27 Exxon, Enron, Exxon. And is not good enough. That's,
03:31 too much junk and not useful. so what's going to happen is is
03:35 there are mechanics, there's machinery inside cell, there's going to be modification
03:41 takes place. And so we're going get rid of the introns, we're
03:45 to protect the DNA by adding stuff it. And then depending upon that
03:52 and its need, you may see is referred to as alternate splicing.
03:56 what we used to think of as gene being encoding for a single
04:00 that's actually not true. It can alternate how splices that piece of gene
04:06 that gene to create different reading frames that you get unique proteins. And
04:12 what this is trying to show you like this one and that one and
04:15 one are alternate transcripts that you're now to be able to translate. All
04:21 . And when you translate it, going to give you a different
04:23 So you get a different protein from closely related but not the same
04:29 So there's some modification that takes And then once you get that,
04:35 you have a message that can then out into the cytoplasm and then use
04:39 machinery of the cell to make the . Now, you see in that
04:45 MRN A, that's what they were to create these new vaccines. It
04:49 an idea that came up about 20 ago and everyone was like,
04:52 it's not gonna work. It's too . And so we got to experiment
04:56 two years to see if they We'll see how it goes. All
05:01 , now, what we're looking at is kind of that big picture.
05:06 right. I want to make a , proteins are what the cell uses
05:10 do the work that it does. right, I took my gene,
05:14 transcribed it, make this RNA and I have to translate it. So
05:18 the second step. And so this going back to that whole central dogma
05:24 to RNA processing the RNA. Now going to take it out and we're
05:27 to read through that and we're going take that RNA code, which is
05:30 the code of nucleotides. And we're to take that code and turn it
05:34 the code of amino acids now to this, this is where we come
05:40 to those different types of RNAs. do I need in order to translate
05:44 ? Well, I need to have processed. M and that's the first
05:49 and all that is, is the of the gene that has been processed
05:52 that I can now read it. not taking the original, leaving the
05:55 back in the safe. I'm taking the blueprint for the contractor to go
06:00 say you make this, if you , I go make another copy.
06:05 second thing I'm gonna need, I'm need those amino acids. Those are
06:08 monomers that I use to make Then I'm gonna need Trnatrn A binds
06:14 . So here's your little Trnatrn A up a single amino acid and it
06:19 that amino acid to the site of synthesis. So T A system and
06:27 we have our RSO and our ribosome our reader. And what it does
06:32 it takes that message and it starts along the length of that message in
06:37 specific way and using that mess that sequence, it invites the tr
06:42 in to bring that amino acid and it takes the, a acid brought
06:46 and it adds it to an expanding . And so you can see that
06:50 , there's the growing chain and what doing is we're bringing them in and
06:53 going to make this chain longer and and longer. And that's protein synthesis
06:56 a nutshell. Now, it's far complex than this. So we're not
07:00 to go through all this step. I do want to just kind of
07:02 point out a couple of things. again, this is not a chart
07:05 you to memorize unless you take In which case, you get to
07:09 it and live with it, memorize . And you know, tattoo it
07:11 your body and all the other fun . All right, and all this
07:15 is basically says, look here is MRN Codon that results in a specific
07:24 acid. And so if you were read this, this would be the
07:26 codon up here as the second one the first base, second base,
07:30 base. And so each of those is the codon. And so you
07:34 just say I'm just going to use up here. If I had
07:37 then that would be pal alanine. so the trn A that has that
07:42 code on would carry phenylalanine or could uh you, you, you so
07:47 could calculate out what all 20 amino which codes provide for that. So
07:53 can read RN A and we can DNA, which would be a
07:57 So the triplet on the DNA is same thing as the code on for
08:02 RN A which would give you the acid for your protein. And so
08:07 one of the things that we learned do is that we, when we
08:09 that code, it was like, , now we figured out everything and
08:12 didn't figure out anything. All So you can kind of see
08:16 this would be the TRN A down at this loop. That's where that
08:20 is located. All right. And what it recognizes in the MRN A
08:25 and that's right there is the amino it's carrying right there at its tail
08:30 . And so this is kind of it would look like, right?
08:33 coming in on this side and you're your amino acid and you enter into
08:38 ribo zone at a specific spot. then what happens is in the middle
08:42 , that's where the extending protein is . And as you're reading along,
08:46 takes this long change and adds it the end of this one. And
08:50 the ribosome shifts over a frame and the trn A that's no longer bound
08:54 kicked out. And so what you're is you're basically going, here's the
08:58 acid add on shift over, kicked and just keep redoing that as long
09:03 that uh as long as you're reading MRN A and that's how you make
09:07 protein. And we do this like pictures we've already seen. So we've
09:13 this picture, right, which is over here? And we've seen this
09:16 and this is basically showing in the here is that extending protein as it's
09:21 along. And in this particular we're on the endoplasm reticulum, the
09:25 endoplasm reticulum, specifically there is a where we can insert that protein.
09:31 what it's going to do is it's to allow that thing to extend and
09:34 . And then now we have our that's inside the endoplasm curriculum, this
09:39 protein will be something that is secreted it's not attached or inserted into the
09:45 over here. This is done up the cytoplasm and you can see it's
09:50 just one, you don't just have and it reads along and you get
09:52 for one. MRN A because of , that modification we do at both
09:58 increases how long it sticks around and enhances its lifespan. And so you
10:04 have an RN A message that can read multiple times at the same
10:10 And then as long as you keep around, you can keep making copies
10:13 copies and copies of that protein until gets the RN A and it gets
10:17 and then you throw it away and start all over again. And that's
10:19 this is trying to show you is , here's that first ribosome with the
10:23 chain on it and then what you're to do is as it moves
10:27 then you add the next one and you add the next one and the
10:29 one. And so you end up these long chains and so one message
10:32 result in a massive amount of So you have this amplification. So
10:38 can see how important regulating this is you want to keep this around for
10:43 very, very short period of time you make too much protein if you
10:46 it around for too long. But process of translation is pretty straightforward.
10:51 you think all I gotta do is and then I'm making the amino acids
10:55 add on to it. Does that of make sense? And I'm changing
11:00 from one language RN a language to language amino acids, codons to amino
11:08 . You guys with me so All right. Now, the thing
11:12 with proteins, proteins are not just sequence, it's not just a bunch
11:17 amino acids in a row. Proteins shape. We talked about enzymes.
11:21 when we talked about enzymes and we enzymes can change their shape and stuff
11:25 that. Proteins have a very specific and that shape when it changes,
11:31 the activity of the protein. So have to make sure we have the
11:34 shape going into all this stuff for longest time. I know this is
11:41 because your computers don't really have But back in the day when we
11:45 had CRTS, the big old £300 screens, everyone had a screen
11:52 And there were two really cool screensavers could get, one was the steady
11:56 and one was the protein holding screensaver he's looking for extraterrestrial life. So
12:00 all the radio signals and they figured these aisle computers, what we'll do
12:04 we'll just make little cute little lines we'll try to process all the signals
12:08 we're getting in a sourcing manner. I was like, oh, that's
12:11 of cool. Never found an All right. The other one was
12:15 protein folding one because you should be to predict the shape of a protein
12:21 upon a whole bunch of chemical and properties. But you can't, but
12:25 takes a lot of computer power to that. All right. Now,
12:29 some reason, cells can just fold . It's really kind of cool while
12:34 being made. And part of the that they do that is because they
12:37 these chaperone proteins that come along and that molecule fold appropriately while you're building
12:46 . Now, I just think of as voodoo. I mean, it
12:50 beyond my kin that we have a or a couple of proteins that can
12:56 every protein in your body fold the way. And this is the gist
13:04 it. You have these heat shock . You don't need to know their
13:09 . I'm not going to ask you a heat shock protein. But you
13:11 these heat shock proteins that come along bind to it and help kind of
13:15 it. But then you have these that literally look like martini shakers.
13:23 then you take that protein and the shock protein and you put them in
13:26 Martini shaker and then you shake it then you open the top and out
13:31 the properly folded protein. You think making stuff up dead serious. That's
13:39 how it works. So, it's I said, for me, it's
13:43 voodoo, someone knows how it's actually on here, but that's in essence
13:47 going on. All right. So protein is folded correctly so that it
13:54 then function proteins that are not folded , don't function correctly and cause
14:00 And so the cell does not like . So it'll either destroy it or
14:05 it will do is if it's disguised , it will keep working in your
14:11 and then muck up stuff. So don't like improperly folded proteins.
14:20 in understanding a protein and what it , there's four levels of organization for
14:26 protein. All right, what we the primary, the secondary, the
14:31 and the quinary structure. If you've biology, you've probably heard these at
14:35 point in your life, these are particularly difficult, but we need to
14:39 of understand this because in order to shape and how proteins interact, we
14:43 to understand that shape comes from The first thing that the lowest level
14:49 organization is simply the amino acid What is the sequence of this
14:53 It always starts with the methionine because always the starting codon is a
14:59 So when you see that a UG encodes math. So that's always the
15:03 one that goes on in its, its life and you read the amino
15:06 and sequence. All right. So just like reading a word that's referred
15:11 as the primary structure. But because all those side chains, we
15:18 we said we're not gonna bother memorizing . All he said, look,
15:21 these side chains, some charged, are negatively charged, some are attracted
15:26 water are opposed or rejected by hydrophobic, lipid or hydrophobic and lip
15:34 hydrophilic lipophilic. All right, we all these side chains and what they
15:39 is they interact with each other in surrounding environment. So that helps twist
15:43 bend this sequence as it's being So part of that sequence comes from
15:50 . And so what we're going to and we're going to get some some
15:54 that kind of pop out because of nature of the sequence of that primary
15:58 . So the secondary structure is a of or a derivative of the primary
16:07 . Now here, what we're doing we're starting to get some two or
16:11 dimensional shape. There's two particular types secondary structure that we see are repeated
16:19 times in proteins that they're interactive in . So the first type I think
16:25 have another slide here. Yeah. first type is is what is referred
16:29 as an alpha helix. And so can see in our little picture
16:31 all the little squirrely or swirly things just a function of the sequence,
16:37 causes it to bend and bend and and it just kind of bends on
16:40 until it creates this kind of coil helix. The second one is the
16:44 sheet, it's more flat. And you can see these little arrow things
16:47 here on the sides, those represent sheets. And here what you do
16:51 you can see the sequence comes up you have a sharp bin that just
16:54 it to go the same way. then there's interactions between the side chains
16:58 kind of hold things together. So end up with these flat areas inside
17:02 protein. And again, our pictures don't do a really good job of
17:06 it. But I don't think these models help you really kind of see
17:11 what that is. But if you're in biochemistry, they do a lot
17:15 this stuff and they talk about what parts do and how they interact.
17:21 that's why these are important is because this shape. You now have a
17:26 type of interaction that can take All right, you create surfaces or
17:31 create interaction point here. Now this three dimensional. And if I take
17:39 whole bunch of three dimensional shapes, still get a larger three dimensional
17:43 right? So if I think of piece of paper, a piece of
17:47 is flat, right? But is in three dimensions, you have a
17:52 ax and a long Y. But also have a very thin Z.
17:55 if I take that piece of paper then I crumple it up. I
17:59 have three dimensional shape. It's just different. So if I take a
18:03 bunch of secondary structure together with other structures, I get tertiary structure.
18:11 , I should be here. Uh terrible. I'm gonna, I'm gonna
18:16 to this picture because it's a little easier to see it. So basically
18:19 it's saying is if I get a bunch of this, I get a
18:22 bunch of that. So that would the tertiary structure of a protein.
18:27 would be the tertiary structure. It's the sum of its parts. All
18:32 . So why use this picture? have no idea but that shape is
18:38 and held in position because of the bonds that we're ignoring for this
18:44 And I just kind of listed them . I'm not gonna ask you what
18:47 bonds are, how they work. you're taking this class at HCC,
18:52 need to know them. You'd have whole electron chemistry. All right.
18:56 don't think it's particularly important that, know, the types of bonds that
19:00 . All right. But the idea , is that the shape is held
19:03 place because bonds, a protein hydrophobic or side chains get pushed inward and
19:15 they're attracted to each other through kinds like things like hydrogen bonds. All
19:21 . And then hydrophilic, the things love water pointed outward. Now,
19:25 have something to interact with. And tertiary structure now has a functional shape
19:31 it can then use to interact with molecules in the cell so far.
19:40 . So primary is the amino acid . Secondary are the small twists and
19:45 or the flat plates, these beta or beta beta plated sheets or the
19:50 helix that give rise to unique regions that protein. And then the tertiary
19:57 is the whole shape of the And then if you get a whole
20:01 of proteins that interact and stay what you now have is what is
20:04 quinary structure. All right. So picture is the one you usually see
20:09 they throw this out there. When talk about quinary structure, they're
20:12 hey, here's an example of quinary . Here's hemoglobin, hemoglobin is what
20:18 oxygen in the blood, specifically in blood cells, not in circulation.
20:24 so what you have here is you one protein, two proteins, three
20:28 , four proteins, and all those proteins are held together as a single
20:37 . That would be an example of structure collagen. The thing that makes
20:40 your skin, right thing that tight you're young but gets loose when you're
20:47 , that collagen has quinary structure. basically three collagen chains that are wrapped
20:52 a rope and then over time that gets looser and looser and looser.
20:57 that's all throughout your skin. This the easy one to see, looking
21:01 a rope is not a lot less . All right. And again,
21:06 may have other things that are associated it. What we refer to as
21:09 prosthetic. So think about someone who's a limb, right? We add
21:14 artificial limb to it. We call a prosthetic. Right. Now,
21:19 do we call them prosthetic because they're proin us in nature? All
21:23 So here these little hem units, things that actually bind up the oxygen
21:28 pigment molecules. They're not amino acid , they're very, very different in
21:36 , but associated with the globin. that you can have this oxygen carrying
21:43 , which is four proteins and four held in place. That's just an
21:49 . You're not gonna sit there diagram explain hemoglobin. All right. So
21:56 organization makes sense, right? It's think about a paragraph. What is
22:02 paragraph is a bunch of sentences, are sentences, a bunch of words
22:07 what are words, bunch of letters it's the same thing, right?
22:13 bunch of letters, secondary structure. those are your words, put your
22:17 together, you get sentences. That's structure, put your sentence together,
22:21 got a paragraph. OK. That's neat way to kind of think about
22:25 . It's, it's what is referred as an emergent property. All
22:29 So if you ever hear that just think as I put things
22:33 new things show up. All So we're kind of backtracking a little
22:42 here. So these are structures you've learned about. So you can see
22:45 is our nucleus next to the nucleus the, it even says up there
22:52 the new plasma curriculum, right from endoplasm partum, we go out to
22:57 LG and then we might have vesicles lysosomes and then ultimately, we give
23:01 out here to the plasma membrane. we said when we started talking about
23:07 , that at the level of the , it's double membrane. And that
23:11 we're doing is we're building membrane that added to the endoplasm reticulum gets pinched
23:16 , sent off to the golgi joins with the golgi and then things get
23:21 off form those vesicles and those lysosomes then vesicles will then move up and
23:26 join up with the plasma membrane. so they, they are served as
23:31 structure collectively, they're separate because they're by this, the transport, moving
23:40 along the way ultimately to the plasma . All right. And we call
23:45 the endo membrane system. All Endo being inside membrane referring to these
23:50 lipid bilayer. All right. all those structures that we've mentioned and
23:57 been talking about serve as part of in the membrane system. All
24:02 generally speaking, when we look at as a function, what is the
24:05 of these things? They play a in metabolism and transport. I'm making
24:09 , I'm processing things and then when have vesicles, I'm transporting them.
24:13 when we talk about protein synthesis, taking place here in the endoplasm partum
24:18 here up in the golgi. When talking about transport, we're talking about
24:22 vescus with movement of lipids. We're about smooth endoplasm reticulum, right?
24:27 detoxification, smooth endoplasm reticulum. So membrane system is more of a collective
24:34 to look at these particular structures in of a whole function from beginning to
24:41 . So when we looked at this said, what does the the in
24:45 do? We're looking at just a process within the larger process of secreting
24:52 protein. Now, when I was your seat and someone explained all this
25:00 to me, it was like, , well, we have these vesicles
25:04 and what do the vesicles do pop the? And then it's like they
25:07 float around inside the cell and they slowly make their way. And I
25:12 like, ok, that sounds There's no rhyme or reason to
25:15 things just go where it goes. in cells just like everywhere else in
25:22 , everything has purpose, everything is directed or driven in a particular
25:28 And we talked about the cytoskeleton. one of the things we said about
25:34 is that they serve as highways to things around the cell. So one
25:40 the things that we use is we motor proteins to bind up to different
25:46 , including vesicles to move them to they need to go, which is
25:51 of cool. All right, which tells you that nothing is done inside
25:55 cell without purpose, which is also of cool because that kind of supports
26:01 notion or an idea that cells are wasteful. They don't waste energy doing
26:06 things, they're directed. All And so these proteins are going to
26:14 attached to these microtubules and they have region that can bind up to whatever
26:19 supposed to carry and then they move things in a particular direction. Now
26:24 always requires energy. So these are ATP dependent. I think I'm going
26:28 have a video posted on canvas or least a link to it so that
26:32 guys can see this and what's going , you know, but honestly,
26:36 , if the Disney company wasn't responsible creating these things, I mean,
26:40 , if, if you saw you're like, this is a Disney
26:44 . It has to be because they like cartoon characters. You got these
26:48 old floppy feet and they look like and they have something that they attach
26:53 their heads and then they walk around this hearing stuff. It's wild.
27:03 this is how we get things to they need to go when that vesicle
27:10 to the membrane, it doesn't immediately attach to itself and then empty
27:15 In fact, it's directed specifically to area where it docks and it sits
27:21 waiting for a signal to merge with . Now, the molecules that allow
27:26 to dock are called snare proteins right , again, this is probably
27:32 there's far more complex than we're going go into. But what I want
27:34 point out here in a, in very simple way is that this is
27:39 , not a random thing. So I'm secreting something, I'm sending it
27:43 the secreting side of the cell and bests is going specifically to a location
27:48 it can bind up and then wait be cold. So, on the
27:53 of my vesicle, I have they call them V snares because they're
27:58 of the vesicle and then they recognize group of proteins on the plasma membrane
28:04 the inside called T snares. That's target snare. So V snares plus
28:09 snares, they come together and then wrap up and they're like, all
28:13 , we are now attached, but what it does is it doesn't open
28:19 , it's just closely affiliated or closely . But when the right signal comes
28:24 , usually some sort of calcium we don't need to understand that just
28:27 . When we get to muscles, go see, see, it's right
28:30 . All right. But the idea that that signal comes along and that
28:34 the vesicle to open up. And the two membranes merge together and that
28:38 then just joins up with the plasma and the material that was inside gets
28:42 out into the external environment. If a protein that is inserted into this
28:50 , I'd be inserted in this direction that my outside, the portion I
28:54 face outside would be where this stuff , right? So I'd be pointing
28:59 and then when I open up that would go like, like,
29:03 so it's like this and then I open up so that I'd be pointing
29:07 the right direction. If this was outside, I can't make my hands
29:10 the other direction, right? So my finger were pointing inwards to see
29:15 when I open up to the it's still pointing outside. All
29:21 So that's how we insert proteins into membrane so that now I can interact
29:26 my environment. So that's what snare do. And this is just a
29:31 . So you can see how it's done. It even shows the calcium
29:34 here. But again, this is something for you to memorize if you're
29:37 in seeing it in detail, this a picture for you to look
29:40 OK. So here we are at Golgi. So we're still part of
29:47 membrane system here. I'm pinching off vesicle. And the question we're saying
29:52 , hey, what can a vesicle ? All right. Well, one
29:56 that I can do is I can materials to the surface, right?
30:01 that's what this is trying to show , right? And so if I
30:05 a material that is being secreted, going to be inside and then I
30:09 join up to the surface. And just as we just demonstrated, I
30:12 release those materials. The second one if I'm a peptide that is supposed
30:17 be implanted, you can see here is the part that's supposed to be
30:20 outward. When I join up, pointing in the right direction. So
30:23 try to demonstrate that to you. third thing that I can do is
30:26 I have enzymes, I will be aside as a lysosome, I concentrate
30:31 enzymes, concentrate protons in there to it really, really locate. And
30:37 now I can wait for a endos come along. Merge with that.
30:41 when I merge with that endo I then digest whatever is inside that endo
30:47 I'm just throwing this slide up here remind you. So you don't have
30:49 go flipping back. Saying, remember looked at this already here is that
30:54 Zoe it's being formed in here is lysosome. And what they're doing is
30:59 bringing them together. So like damaged organelle, something else I've pinched
31:05 each of these, I bring them and whatever is in one of those
31:10 , lysosome destroys because of the concentration those enzymes is the only place that
31:20 have proteins and other things that need be stored at. They only found
31:24 endos. Do you have proteins in cytoplasm? Do you think they can
31:29 bad? Yeah. Do we have have a way to get rid of
31:33 ? Yeah. So we have This is the garbage disposal of the
31:38 . If lysosome is the stomach of cell, here's the garbage disposal.
31:42 happens is pro pro uh proteins in cell. Um When they're doing their
31:48 , everything is going great. You , everything's fine. But when they
31:50 malfunctioning, there are machinery inside the that recognizes things that are going
31:56 And what they do is they tag , right? They kind of go
31:59 and it's like, oh this is . It's like right before you do
32:02 garage. So you're going through the and you're like, yeah, this
32:04 in that box, this goes in box. Same thing. It's like
32:06 come along and we tag it, protein or the molecule we use to
32:10 these things are called ubiquitin. The name for a protein. You
32:15 do you know what ubiquitous means Right. On campus, students are
32:25 . There. You have a vocabulary for the day. All right.
32:28 you don't need a calendar and just me, I'll give you a big
32:31 , right? So Ubiquitin is named it's everywhere Great. Thank you for
32:38 help professor. Right? I this is, this is what biologists
32:41 . We name things for what they or for what they look like.
32:43 like, well, we find this to there's stuff everywhere. So we're
32:45 gonna name a ubiquitin. Great. you. Very unhelpful tells you nothing
32:49 it does, right? But what does is we take ubiquitin and we
32:55 proteins that need to be destroyed. then that is a signal for something
32:59 to come along and grab it and , hey, you get to go
33:01 the proteome and the proteome grabs it then grinds it down into a bunch
33:05 amino acids. And what can you with those amino acids? You can
33:08 them and you can use them to new proteins and life goes on.
33:14 if everyone accuse you of not being because you fail to recycle, you
33:17 that trash can you just throw that cup in it? No,
33:21 no, no, no, I'm stuff all day long amino acids,
33:26 example. Yes, ma'am. And . And this all right. That's
33:33 good question because like wait a you told me lyses break things down
33:38 they do. But we the way of works. Remember it's a vesicle
33:43 the materials in it. So you to bring something is another vesicle with
33:48 in it to it. So let go back a slide. So we
33:51 see this again using this as an . All right. So what this
33:55 is trying to show you is here an endo zone being formed with like
34:01 bacteria in it here. This is you an organelle. So let's say
34:07 a mitochondria has gone bad or over it's like, oh well, here's
34:13 that I'm just bringing in. That's a big Ovega zom, right?
34:18 oh, I don't know, proteins the cell is picking up through uh
34:23 sort of binding mechanism. That's what was trying to show you is
34:25 see there's a receptor and the little things are the things I'm binding
34:28 But in each of these cases, forming a vesicle of the, of
34:33 material. And then what am I do is I'm gonna take that vesicle
34:37 merge it with the lysosome. what I'm doing is I'm merging two
34:41 together with the proteome. There is vesicle, what we're doing is we're
34:47 out here in the blue. if I have a protein that's gone
34:51 , then that proteome is going to delivered or it's gonna be given that
34:57 protein. There is no vesicle It's a very good question.
35:11 protein. Um That's probably another way can think about it again though.
35:16 , the primary difference here is functionally with the vesicle. So proteome by
35:21 nature, you can look at its prote. So it's basically saying I'm
35:26 proteins, it doesn't destroy DNA. have other enzymes that do that in
35:31 location where you'd find DNA. We enzymes that are responsible for breaking down
35:36 . All right. And again, would be not a proteome. Those
35:39 be RN A. All right. inside a, a lysosome, you
35:45 have enzymes that break down whatever happens be inside that vesical. So for
35:51 , if you're looking at a what is that bacterium gonna have in
35:55 ? It will have proteins, easy, but it will also have
36:00 acids, right? Because bacteria have material, it will also have lipids
36:06 it has a plasma membrane. So gonna have to have something that deals
36:09 all of that stuff. And so regard to the lysosome, yes,
36:12 going to have to have enzymes that responsible for breaking all that material
36:16 So that is a good way to about it. But again, a
36:21 difference there lysosome is a vesicular The things that is destroying are in
36:27 as well. Yes. Mhm So don't know enough about Autopay to know
36:42 that's true or not. Um So became this really, really exciting mechanism
36:49 they learned that this is how cells with large organelle damage, right?
36:56 so it became this like, maybe this is the way to if
36:58 can, if we can somehow understand mechanism, we can use it as
37:02 way to deal with cancer. So why it became a really hot topic
37:05 everyone started exploring it. Unfortunately, , I'm, I was long past
37:11 interest in that area to really kind pay attention and I did have worked
37:15 it. But again, it was terms of cancer, I don't
37:18 in terms of like, all if you're depriving yourself, if you've
37:21 through all your fats, is this you start breaking down your muscle?
37:26 that is. So this, this is if you are in a state
37:30 starvation and presuming you're having water put your body, right, then your
37:35 will first burn through all your protein first burn through all your fat and
37:39 it will start breaking down proteins. is it this mechanism? I don't
37:42 , it's likely that it is, I don't know for certain.
37:46 totally useless, aren't I? you can nod your head and say
37:52 before we move on. All So this is a really good
38:01 Well, I mean, that is great place for good questions and those
38:04 good questions. Um What we're gonna is we're gonna shift gears.
38:08 we're going to start dealing with this of all right. Remember that we
38:12 we're going to kind of go into physiology. I need to move something
38:16 the cell, whether it's through the or through some part. So how
38:20 I go about doing that? And we're going to be looking at these
38:23 types of mechanisms. All right. , the first thing we need to
38:28 is, is a very simple definition what is diffusion. All right.
38:32 that first bullet point up there is definition, it's the tendency of molecules
38:37 spread out evenly into their environment so there is basically an equilibrium or an
38:44 distribution between them. All right. that's, that's ultimately what diffusion
38:50 All right. It is dependent upon things. 22 basic things. It's
38:55 concentrated are those? All right. in other words, if we have
39:00 over here, but none over we would expect diffusion to occur rather
39:05 . All right. And the reason is that all the molecules have some
39:08 of degree of energy in them. when you put them all close
39:11 that energy is them bumping into each and they start colliding. And so
39:15 start spreading out until they ultimately spread to the point where they're colliding with
39:19 other at the same rate because of diffusion or that, that distribution.
39:26 this the steeper that slope the faster rate of diffusion. So if they're
39:32 already evenly distributed, they're not going run into each other with a high
39:35 of frequency. It's going to be similar degree of frequency as they would
39:39 they were all evenly spread out. right. Now, if you can't
39:43 this, we call it the the steepness of the gradient. Think
39:47 being in Houston and, and getting a skateboard right where it's flat.
39:52 you move when you get on a surface on a skateboard? No,
39:58 stand on it. All right. , let's go ahead and increase the
40:02 a little bit. Let's say you're a very low slope and you stand
40:07 the skateboard on the top. Are gonna start moving? Yeah.
40:11 What if you go into a space has the steepness of this room and
40:15 get to the top and you get a skateboard. Would you go faster
40:18 with, you have a shallow Yeah. All right. And then
40:21 just go ahead and crank that all way up to almost 90 degrees.
40:25 do you think even faster? So the steepness of the slope
40:31 In other words, the more concentrated am in one area and the less
40:34 the other area, the faster I'm to diffuse the second form or the
40:38 thing that matters is the degree of . Temperature is kinetic energy. That's
40:45 it reflects. It's how much energy putting the system. You guys know
40:48 sweet tea is, you know how make it. No. All
40:53 This is an important thing. You live in the south right now.
40:56 tea is what we drink down All right. I know some people
41:01 spot because you're like, my grandma sweet tea, right? Or my
41:03 makes sweet tea. You gotta know you're an adult. Now. You
41:06 to know how to make sweet It's real simple. You boil tea
41:09 and then while the water is still , you put in the sugar directly
41:13 what does the sugar do? It ? It dissolves right in if I
41:17 to a restaurant and order an nice and then I put the sugar
41:20 where does the sugar go right down the bottom? And it sits
41:24 this gooey mess. So what do have to do? Mix it?
41:28 have to stir it. All But we're scientists here, we're not
41:30 it. We're providing kinetic energy. right, we're basically forcing the
41:37 And so because they're spreading out, dissolving, they're moving away from each
41:42 . And that's what that diffusion All right. So, you
41:45 if you ever get lost, just of the sweet tea example.
41:49 there's already heat in the system. put it in the sugar, the
41:52 just diffuses very, very quickly. right. So this is, this
41:57 what we're kill your body do. trying to spread out as best they
42:03 in with that throughout your entire body the fact that we apartments in
42:08 All right. And so there are ways that these, these particles can
42:13 move using simple or not simple But using this definition of diffusion,
42:19 I'm always trying to move down my gradient, if if nothing is impeding
42:24 , I can move just fine. right. So that would be an
42:28 of simple diffusion, right? So diffusion, you don't need any
42:33 Even if there is a membrane that membrane is not serving as a
42:37 . It's not even as far as concerned. If that barrier is permeable
42:42 you or you're permeable through that then you'll just diffuse just fine.
42:47 would be simple diffusion. All So it's only dependent upon the concentration
42:53 . It's not a regulated process. going to see different types of this
42:58 just a moment. Now, most the molecules in your body are ionic
43:03 some way, shape or form. other words, it carries some sort
43:05 charge to them, right? Or other thing is that they are either
43:11 or lipophilic, meaning they love the or they hate the water. All
43:16 . And so if you love the and hate fat because you can't love
43:21 . You're, you're one or the , you can't pass through a
43:25 All right, that membrane is no permeable to you. So you some
43:30 of help to get past that right? So that help means you're
43:37 the movement of that molecule. That's the help is. So we have
43:41 is called facilitated diffusion cell diffusion I can go wherever I want to
43:47 what is the concentration gradient. I'm to move from the area of high
43:50 area of low concentration facilitated diffusion. still dealing with that high to
43:56 but I can't cross that barrier to to the low. So I need
43:59 help me along the way. That's these represent. All right. So
44:04 can have channels or we can have . A channel is simply a structure
44:12 creates a hole through the barrier. right, that's what this is showing
44:17 . It's literally a water filled So that if I'm a water loving
44:22 , I can just pass on through hole pretty simple. All right,
44:28 channel could be something that has a to it, it can open and
44:34 . But generally speaking, we're talking the gate is open, it allows
44:38 the free flowing of materials between the spaces. A carrier. On the
44:43 hand, literally has to bind, bound up by the thing that needs
44:48 be moving. All right, it's open to both sides. At the
44:52 time, it's open in one And then when it binds up the
44:56 that it needs to move, then causes that protein to change its shape
45:01 open up the other direction. And it changes its shape, it is
45:04 longer capable of binding the thing that carrying. So it pops out and
45:07 , it goes all right. So are some of the basic kinds of
45:13 from which we get all these other complex types of movement. All
45:19 So for example, this doorway over is an example of a channel,
45:25 this channel open or closed, But if I were to take those
45:30 and prop them open, anything that pass through the door is going to
45:34 through the door, students, dogs but not trucks, too small
45:41 trucks. Ok. Carrier, a is more like um have you ever
45:49 in those types of doors like at or at airports, the rotating
45:54 right? You have to kind of walk up to it and it's like
45:58 your timing right? And you like in and now it's like right then
46:05 go to the other side and you out through the other side.
46:07 that's more like what a carrier Notice it's only open one side at
46:10 time. Ok. Now a type facilitated diffusion is, well, it's
46:22 let me back it up. It not a form of diffusion. And
46:25 reason it's not a form of diffusion and moving things from an area
46:29 high concentration down to an area of concentration. Another type of transport,
46:35 type of movement is this active we might refer to facilitated transport as
46:43 transport so you can kind of distinguish that way here. What we're doing
46:49 we're moving something from an area of concentration to an area of high
46:55 So things aren't moving down their concentration , they're moving, moved against their
47:01 gradient, right? So if I something on the floor that belongs on
47:06 table, which is basically my entire because I have four kids,
47:11 So what do I have to I have to go down and use
47:15 and I have to go take that and I pick it up and I
47:19 it on the table. It was expense of energy usually mine.
47:25 So with active transport, that term should tell you energy is being used
47:31 we're gonna go and show you these just a moment. But there are
47:34 types one where I'm using a directly energy in the form of A
47:38 directly. All right. And so what this is saying as primary does
47:44 secondary active transport doesn't use energy It uses stored up energy energy that
47:52 from a TP and now has been into potential energy. And I'll give
47:56 an example of this when we get these, but I want to move
47:59 the other forms of, of uh before we go into more details.
48:07 ? But when you see active think has somehow been involved either directly or
48:13 . OK. Primary is direct secondary indirect. When we deal with
48:20 there are some characteristics that you need understand. All right, di diffusion
48:24 dependent up a couple of things. first off size matters. So the
48:29 the solute, the bigger things the more easy, they bump into
48:33 . So it slows things down. you have itsy bitsy tiny molecules,
48:36 move faster than big molecules. All way to remember this. People like
48:43 , adults are large, three year are tiny. If you go to
48:49 football game with a three year old they let go of your hand,
48:51 run between everybody's legs. You trying catch them is you bumping into everybody
48:55 to catch them, right? So , fast, bigger, slow.
49:03 the rates of diffusion slow down for materials. Membrane thickness matters. All
49:09 . So if I have to travel point A and point B and that
49:14 is like stuff in between us, gonna take me longer than when there
49:18 nothing in between us. All So that thickness matters. The surface
49:26 . If I look at a chain fence, right? The chain link
49:30 has holes about so big me throwing golf ball at the chain link
49:36 some are going to get in, are not, right. So if
49:39 , if I was looking at what the rate at which I could throw
49:41 balls through a chain link fence, be a lot slower than me
49:46 um, say marbles through a chain fence, right? If I make
49:50 hole bigger, then it increases the at which I can throw the golf
49:54 through. So the surface area through you're traveling matters. Another way you
50:01 think about this is, um, now, the number of people that
50:05 leave this room through these two doors , is limited by the size of
50:09 doors, right? But we have lot of surface area on the
50:13 If I added more doors, I go through more quickly, right?
50:18 be the surface area thing. Uh already talked about steeper the slope,
50:22 faster I go uh temperature is adding more energy, things want to start
50:27 into each other a lot faster. the higher the temperature, the faster
50:30 rate of diffusion. And then the viscosity solution, which means the
50:34 material I have in there, the likely something's going into something else.
50:38 that is what viscosity is thickness, much material is in there is really
50:45 of what we're looking at. So will hear terms or read terms,
50:51 think in the book and talk about flux refers to the rate of
50:55 So here I've got a high concentration nothing. And so the rate of
50:59 for this molecule for red is basically very, very steep. So it
51:04 quickly move down its concentration gradient So its flux is its rate of
51:11 . All right. In this picture here, I've got lots of red
51:15 no red. I got lots of and no blue. So we have
51:18 rate of diffusion that are independent of other right red moves at its
51:24 blue moves at its rate. Now can be affected by the permeability of
51:28 membrane and so on. But what looking at here, the question we're
51:32 is what is the rate of diffusion that particular it? All right.
51:39 is the difference between the movement from to B and from B to
51:47 All right. So even though we that we have a uh basically an
51:51 rate here as we start moving it's going to start slowing down because
51:57 time a molecule moves over here, potential for a molecule to move over
52:00 . There's a one in three chance over over here. That's a one
52:04 seven chance that the molecules are moving the other direction. So the difference
52:07 those two movements is net flux and they're moving at the same rate in
52:13 directions, that is what equilibrium All right. So this is
52:19 even when you have multiple molecules, have to consider both of them.
52:25 we also have something called bulk flow bulk flow is something that we see
52:30 the body. But we don't really about it all that much when you
52:34 in. What are you breathing Hey, thank you. II I
52:39 that. A lot of people try get real scientific and oh, I'm
52:41 in oxygen. That's true. You breathing in oxygen. But what else
52:44 you breathing in nitrogen and carbon And a whole bunch of stuff that
52:50 don't want to bother memorizing because it less than 0.000 something percent of the
52:55 solution. But the majority of stuff breathing in is nitrogen, followed by
53:00 , followed by carbon dioxide, followed a whole list of things like
53:04 especially in Houston when we have a environment, stuff like that. So
53:07 I breathe in my body only wants of those things. What does my
53:12 want oxygen? Right? But bulk says I create a pressure gradient that
53:19 in all the stuff, the air then I'm gonna deal with the individual
53:26 down their particular pressure gradients. So moving carbon dioxide from my body into
53:32 lungs and I'm moving oxygen from my into my body. And so that's
53:36 bulk flow, bulk flow, it's the air moving in. And then
53:39 I breathe out the air moving out some slight changes in the concentration of
53:46 particular gasses in the body, we bulk flow as well. When we
53:51 materials from the blood into the interstitial or from the plasma into the interstitial
53:56 and vice versa. We're not nitpicking well. I only need glucose to
54:00 out. I'm only moving the fat . No, no, it's all
54:04 it. All of it moves in directions, but we pick and choose
54:09 to go into particular cells from the fluid. But again, we're dealing
54:13 pressure gradients driving all of the fluid all the stuff in the fluid that's
54:20 flow very, very different than these things that we're talking about with regard
54:25 diffusion. So a membrane is considered be permeable when it allows a given
54:32 to pass through and impermeable when it allow a given substance. But there
54:37 a lot of substances. And here's an example of some of the substances
54:41 your body. This isn't even a list. Obviously, it's not a
54:44 list. So your plasma membranes are to some things and impermeable to other
54:51 . And because of that, we our membranes. These plasma membranes selectively
54:59 and selective permeability centers around. For most part, the degree of hydrophobic
55:07 lipophilic. That's the same term or hydrophilic versus N slash lip AOB for
55:16 , molecules like oxygen and carbon dioxide no polarity and they, they lack
55:24 sort of degree of hydrophobic or They're neither hydrophilic or hydrophobic, they
55:31 go. So membranes are selectively permeable these gasses, gasses just move wherever
55:39 a pressure gradient right. But when talking about, for example,
55:43 ions want to be wherever there's they're hydrophilic. So, a membrane
55:48 impermeable to these charged molecules. All . Well, what about glucose?
55:54 doesn't have a charge? You're It doesn't have a charge, but
55:58 big. And if it's too big can't pass through. But what about
56:04 ? See, water passes through just ethanol does. Why does water?
56:09 , water is weird. Even though a polar molecule, it's a tiny
56:13 molecule. So it just goes where wants to go. It breaks all
56:17 rule, all the rules. People that yes, that's, that's
56:27 a really good question because I kind just assume. So, hydrophilic means
56:31 loving. All right, the opposite hydrophilic is hydrophobic. All right.
56:37 hydrophobic is water hating. So the term or the or the the equivalent
56:44 is if you are hydrophilic, that you are likely lipo phobic,
56:51 Meaning if you love water, you fat and if you hate fat,
56:57 love water and there's the other, opposite is true as well. If
57:00 love fat, you hate. Do just say the same thing again?
57:04 getting lost here. If I'm water , I'm fat, loving. If
57:08 water loving, I'm fat hating I got it right. Poor and
57:14 are water loving. All right. you're not charged, if you're not
57:20 , you're likely fat loving. All . So you can see this just
57:27 of gives you a demonstration of what it is that allows you to pass
57:31 the membrane. And so if the is selectively permeable, that means we
57:36 to have mechanisms to move the things want to move. And that's where
57:40 these different things come in where diffusion important. So these would be governed
57:45 simple diffusion. But these over here going to be governed by one of
57:50 facilitated mechanisms. All right, and there's water. Oh My goodness,
57:57 just crucified. You guys heard of , right? You want to try
58:02 give me a definition of osmosis or you just want me to just,
58:05 , see here's the thing, if taking in chemistry, they're gonna give
58:09 a definition. If you take it physics, they're gonna give you a
58:11 weird, weird strange definition. And in biology, we give you a
58:15 different one than chemistry and then you of walk around going. I really
58:18 understand osmosis. This is what osmosis . It's water diffusion. What do
58:23 know about diffusion? It's a molecule moves from an area of high to
58:27 area of low concentration. All problem is in chemistry, they don't
58:32 about water, they care about the in the water. And so when
58:36 trying to give a definition about osmosis you're focusing on solute, it turns
58:42 backwards. So what they usually tell in chemistry, it's moving from an
58:46 of uh uh low solute concentration in area of high solute concentration, which
58:50 backwards in what you just learned, ? I mean, it's not,
58:54 it sounds backwards. Osmosis focuses on , water, moving down its own
59:00 . So if I have 100% solution water, that means it's 100%
59:05 But if I have a 50% solution water at 50% water, 50%
59:10 If I focus on the water, moving from 100% to 50% water is
59:14 down its gradient. See how that . All right. Now, water
59:22 move through a membrane because reasons it's and we don't want to go
59:29 All right, just go with it and it can pass through. If
59:35 want to move, move water you give it a channel. It's
59:38 an aqua. All right. So diffuses can do, do that as
59:45 . But what we're doing is we're to be moving in ways. That
59:49 of sound weird. Now, what gonna do is I'm gonna try to
59:52 this simple for you. All I can't always promise it's going to
59:56 simple, but I try. All , I'm gonna come to this slide
60:00 we're going to get here in just second. Oftentimes you'll see this picture
60:04 it's like, look, I have , the red dots are supposed to
60:08 the concentration of solute around the blue , which is the water. So
60:14 , do you see how the picture flips it on us in terms of
60:17 we're trying to focus on. What care about is the water. But
60:21 we're trying to do is we're trying create equilibrium in the system. In
60:23 words, we want balance in terms the water and the solute together.
60:28 what we're trying to do is we're to move water wherever there are solute
60:30 that we dilute the solute out so both sides have the same dilution.
60:35 that kind of makes sense? So if I have 10 particles of
60:39 over here and one particle is something here, I'm gonna try to get
60:43 so that I have an equal amount particles versus uh to water ratio.
60:49 , that's, that's what what the try to do. But if I'm
60:52 you just focus on the water, way does the water want to
60:55 It wants to go until the two have the same water concentrate. Does
61:01 makes sense? So water is going keep flowing in this direction until it
61:06 . So what prevents it from flowing direction is pressure. Every liquid has
61:14 pressure, it's called a hydrostatic Hold up your water bottle. Thank
61:21 . Water in there is the water out going everywhere. No, but
61:25 wants to, it wants to Why? Because it's a pressure trying
61:29 escape. You can put it You have to hold it up.
61:33 . It's trying differently. But the is creating a, uh, an
61:37 pressure that prevents the water from I have fluid in here. It
61:42 hydrostatic pressure. It wants to escape well. It can't, the metal
61:46 allow it. Pick any sort of that you're carrying water. If you
61:50 water in a paper bag, will escape. Yeah, because there's not
61:55 pressure to hold the water in, it will slowly seep out.
61:59 So water wants to go where there's water. But if there's an opposing
62:06 , then it won't move. So water in here and in there and
62:10 the other drinks that's pressure in there called the hydrostatic pressure. All
62:15 So it's the pressure that a fluid outward away from its concentration. That's
62:22 first one. All right. the osmotic pressure is the opposing pressure
62:30 a fluid that prevents the movement of fluid. Now, I'm gonna give
62:34 an example and hopefully this will make . All right, you're going clubbing
62:39 your friends, but you own a car. Do you have? You
62:43 what a smart car is? How people can you fit in a smart
62:47 ? You got one, how 323 you guys aren't trying, remember
62:52 going clubbing, you're college students. many people. Can you fit in
62:56 smart car? Hey, I see . Yeah, it's like, I
63:01 know, I haven't tried yet. not the question, how many fit
63:04 a smart car comfortably because I think that answer isn't one. Right.
63:09 how many people can you fit in space? There is a volume inside
63:12 space and I can start shoving people there. Right. So I'm getting
63:16 , number seven people are lying across laps. I get to number eight
63:20 I push someone in, someone's going pop out the other side,
63:24 What we've done is we've reached the where the pressure inside the vehicle is
63:27 great that it causes another molecule to out or causes the person to pop
63:31 . Osmotic pressure is like that. the hydrostatic pressure of that fluid.
63:36 one molecule comes in, it's so that it says, uh uh and
63:39 that molecule right back out or kicks molecule out the other direction. So
63:44 the point where osmosis stops and when reached the point of equilibrium. All
63:50 . So it's the opposing pressure. so hydrostatic pressure is the pressure all
63:55 have. But the osmotic pressure is hydrostatic pressure that opposes the inflow of
64:02 into that space, right? So inside that little smart car pressure is
64:07 up, pressure is building up and you put one person in there and
64:12 person pops out right. That would the osmotic pressure if the people were
64:18 molecules that makes sense. Sort All right. That is correct.
64:29 question with hydro osmotic pressure is a of hydrostatic. Yes, it is
64:33 type of hydrostatic pressure. The type opposes movement into that space.
64:43 though you're going into nursing, this the important term tonicity. All
64:48 This where flips it all back back . It says we're gonna ignore the
64:52 for a moment. We're gonna ask question, what's in that water?
64:56 right. So you can see the hypo iso hyper hypo is less iso
65:01 same. He is more. The half of the term deals with the
65:10 tonic. It's the stuff that's in water. So it says less
65:16 same solute, more solute. And when you're looking at a solution and
65:21 asking the question, what is gonna when I put a in this
65:27 All right. Is the water going flow? Oh My goodness. It's
65:32 . But they're flipping it on right? If I have low
65:37 what do I have high water? I have high solute, what do
65:42 have low water? So notice they're you focusing on the wrong thing because
65:51 want you to, they usually, you have this question asking which way
65:53 water flow? If I put a into a hypotonic solution, if I
66:00 a cell and put it in a solution, there's more water outside than
66:06 that cell. So water is going flow into the cell and cause the
66:10 to swell up. And in some pop, that's a bad thing,
66:21 ? If I give a cell and it into an isotonic solution, nothing
66:26 because it says it's the same water both sides of that membrane. But
66:30 I have a hypertonic solution, put cell inside that there's less water in
66:35 solution than inside the cell. So cell shrinks up as the water
66:41 All right. And you're saying, , why do I care why you
66:44 this is important if I'm going into ? All right, a person comes
66:47 you dehydrated into the hospital, you a, you put an IV into
66:53 arm. What do you want inside IV? You don't want anything that's
66:58 to cause those cells to pop, you need to give them more water
67:03 they're dehydrated. So what you do you lower the slope for the movement
67:08 water. So you give them a like say for example, D five
67:12 which is a 5% dextro solution, ? So water moves slowly in.
67:19 it doesn't cause the cells to All right. Oh They got red
67:23 , their eyes are so dry. do you give them Visine? Which
67:27 an isotonic saline solution, right? it's basically saying it has the same
67:33 concentrations but what you're doing is you're moisturizing the surface of your eyes.
67:40 right. So tonicity is the ability a solution to change the state of
67:46 cell, right? That you put that solution? How are we doing
67:51 time? I haven't even bothered looking . Oh, man. So I
67:56 some time here. Good. All . I know. You're like,
68:00 ? Yeah, I still got All right. 12 minutes here.
68:04 um when we talked about these transport , what we're basically saying is what
68:08 they transport? They, they have very specific things. So channel
68:12 as we said, they create these filled canals. And so they're going
68:15 use primarily to use very, very materials like ions to pass back and
68:20 across the membrane or water carriers. the other hand, on the other
68:25 , are looking for bigger things, huge things, but bigger things like
68:29 molecules or amino acids use carriers as way to move things across the
68:34 All right, there are different types channels. All right, what we
68:39 is that channels have a gate to , that gate can be opened or
68:44 . So what is the trigger that them to open and close? That's
68:46 modality is the word we use. there are different types of modalities you
68:50 have voltage. So voltage basically says is the charge build up around that
68:56 ? So when you change the it causes the change in the shape
68:59 the protein I can have a So a ligand is a word that
69:04 , that means molecule that binds something . And so I can have a
69:10 bind to the channel that causes the to open or close. It's just
69:14 a key, right? I can something that's mechanosensory. If I twist
69:19 manipulate the membrane of the cell, manipulation of that membrane causes the manipulation
69:25 the shape of the molecule which causes to open or close temperature is another
69:29 . These are just examples, these the most foremost common types, but
69:33 are other means of opening and closing . All right, I brought primary
69:42 up. I said active transport is in which direction with or against your
69:48 against, right. So I'm going low to high. So I need
69:51 . So in this case, what going to do is I'm showing you
69:54 is the most common type. this particular type of ATP ace or
70:01 is an at a meaning it already an enzymatic portion to it that causes
70:07 the the carrier to change its I just said give it energy and
70:11 does. So. All right. this is the sodium potassium A TP
70:15 pump. These types of of pumps are active transport. So when
70:22 hear active transport or pump, they synonymous with each other. So
70:28 what we're doing is I want to potassium out of the cell or sorry
70:34 into the cell. And I want move sodium out of the cell.
70:37 have lots of sodium out of the . I have very little sodium in
70:40 cell. So me moving sodium out the cell is against its gradient.
70:43 have lots of protein or sorry, lot of potassium inside the cell,
70:47 little potassium outside the cell. So pump is serving to create that inverse
70:52 . I'm using the energy to do . And so this pump is allowing
70:57 to move things two things in opposite . And this is one of the
71:03 that we create an imbalance between these . Now, if I put a
71:07 bunch of sodium out here that I'm and pumping and pumping, I just
71:11 energy to create a gradient that favors movement of sodium into the cell.
71:17 lots of sodium outside the cell, little sodium inside the cells. Potential
71:22 . Let me make it so that guys can see this clearly if I
71:25 1000 ping pong balls lying around the and I start throwing them into the
71:30 , right? The first couple of pong balls is not a problem.
71:32 after a while every time I open door that those ping pong balls want
71:35 come out, right? So it's to take energy for me to move
71:38 into that door. But the moment open that door, they're just going
71:41 want to flow on out that's potential . So those ping pong balls stored
71:45 inside the closet potential energy. So act of transport uses energy directly to
71:54 molecules against their gradient. Here's another of that, this is a proton
72:00 when we talked about the lysosomes creating low ph environments. That was what
72:05 going on here. We're using these of pumps to use energy to pump
72:10 into the lysosome inside the cell becomes lot or inside the uh the
72:16 the lysosome much, much lower ph , very acidic secondary active transport takes
72:25 of that um pumping system. So I did, I pumped a whole
72:30 of sodium outside the cell. Sodium to come into the cell, but
72:34 want to move something into the cell its gradient. Let's think of things
72:38 we can move inside glucose amino All right, glucose is basically energy
72:45 jet, right? It's basically a bunch of energy that just needs to
72:50 released from all those bonds. But don't want to use energy to move
72:53 . Doesn't that sound like a stupid ? Right. So what I want
72:57 do is I want to store up to move energy so I can use
73:03 a thing like a glucose transporter that secondary active. All right. What
73:09 that mean? Well, if sodium to come in, it can come
73:12 as long as it brings a glucose it. All right. So glucose
73:18 to come in but I can't because would be moving uphill. So I'm
73:23 use the potential energy stored in that gradient to help move something against its
73:30 . So in this particular case, moving in the same direction, this
73:34 called sim I'm moving in the same . So one is moving down its
73:39 , the other one is moving up gradient, but they're both going in
73:42 same direction into the cell. This how we move glucose and amino acids
73:47 cells by using the pump, which uses a TP directly. I
73:53 potential energy that potential energy is that transport to move the glucose into the
74:01 against its gradient. That kind of sense. Now, I used to
74:06 an example but I'm running out of one and two. I'm finding my
74:11 doesn't work anymore because I used to the example of Ladies night in New
74:15 when I was in college. But guys are all too young to drink
74:22 for a couple of y'all right. two when I give this, both
74:27 you guys just stare at me like ladies night. So I'll give it
74:32 day if you guys want to hear , I'll give you the example.
74:35 right now, no, you there nothing on the slide, you need
74:39 memorize what I'm showing you on this . And on this slide is that
74:46 idea of active transport and secondary active is conserved over and over and over
74:55 . So if you learn what active is once and understand it, you'll
75:00 it again. So this is the we looked at, you'll see it
75:03 and again and again, I think another one there. Yeah. What
75:12 secondary active transport? Well, here's channels, but here's secondary active
75:17 Secondary active transport. This is antiport they're moving in opposite directions there,
75:27 , import, antiport, antiport, . All of those are secondary active
75:35 mechanisms. And this is just touching tip of the iceberg. There are
75:40 of these if you learn it once learned it 1000 times. All
75:48 Ok. Man, I didn't even to vesicular transport. All right.
75:52 we come back, we'll deal with transport. It's not that hard.
76:04 . Three Kelly, what's up
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