| 00:23 | Folks um Welcome. Mhm. So loud. So a couple announcements I |
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| 00:38 | these out earlier um this morning so one of the main ones there is |
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| 00:47 | um schedule er hoops right here so don't think it's been advertised yet on |
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| 00:54 | casa site but if they are going to form The scheduler is available on |
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| 01:05 | . Okay and by Friday it means midnight so very early in the morning |
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| 01:10 | Friday. Uh of course if you a particular time stop there will be |
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| 01:16 | stops throughout the day. So we , the exam is not for two |
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| 01:22 | from friday but you typically have like range of times on two days to |
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| 01:27 | from. Okay so but if you wanting a particular time you may want |
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| 01:35 | I guess we have a midnight but just to let you know uh other |
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| 01:40 | that so this is basically a weekly here so it's gonna be a blackboard |
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| 01:47 | every week And so this week is different than this. Chapter three. |
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| 01:52 | work is due next Monday and today gonna not not quite finish up part |
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| 02:01 | of chapter three but we'll get through of it and then we'll start finishing |
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| 02:05 | on thursday and then start on chapter . Chapter four is growth. Okay |
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| 02:12 | we'll talk about that starting thursday so the clicker data so clicker data from |
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| 02:20 | was delayed posting it but I posted so take a look um I will |
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| 02:30 | the system again. Want to upload points from today so if you use |
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| 02:35 | clicker, maybe it wasn't registered or . Um It should pop up after |
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| 02:41 | refreshed today. So anyway, just an eye on it if you're, |
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| 02:46 | main thing is if you're using a and it's registered but you're not seeing |
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| 02:50 | and that's obviously need to get that . Okay, so um anyway, |
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| 02:56 | I just wanted to start really with kind of a recap of do you |
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| 03:03 | any questions? Certainly let me but just uh we went through the |
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| 03:10 | negative gram positive cells and so what's from their envelope? What's similar and |
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| 03:19 | these are probably terms that should be with. There was a we had |
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| 03:24 | bunch of these questions. Last time was a question on the quiz like |
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| 03:28 | . So, you know, you a visual like this, that or |
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| 03:32 | variation of this, you know, basics of the structure and the terms |
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| 03:41 | layer. Uh so um are there questions about about this? So um |
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| 03:56 | , so we'll finish up part 1 and then part two is pretty much |
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| 04:02 | of I said, okay, right we're kind of what's in the |
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| 04:07 | What's, what's going on here, of what's in the south? |
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| 04:12 | And that's basically part two is all . So little bit first about, |
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| 04:17 | talked about the structure of the cell and, and so so we'll get |
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| 04:24 | this a little bit today about um of differences between uh rod shaped |
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| 04:35 | Cells will caucus being circular but sellers rod shaped cells and similar ones and |
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| 04:42 | are some differences in terms of the involved. Okay. And so now |
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| 04:48 | rod shaped cells and we'll see this component here in a second we'll talk |
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| 04:53 | little bit more. These are one the side a skeletal elements. |
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| 04:58 | Um We of course have a very complex, highly organized um uh set |
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| 05:07 | skeletal system. Act 10 and micro and filaments. Very complex bacteria have |
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| 05:16 | as well but not to that degree but they do have some components that |
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| 05:20 | very similar to things like active and function. Okay. And M. |
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| 05:27 | . E. B. Is one those. Okay there's three of these |
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| 05:31 | look at it again, it'll be few minutes. We'll delve into this |
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| 05:35 | . But M. R. B. So you see a rod |
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| 05:38 | sell their uh these have think of as like a cold arcs of this |
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| 05:49 | . R. E. V. or like scaffolds. It's wherever and |
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| 05:54 | is occurs. And so and they the length of the cell so rod |
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| 05:59 | cells as it grows well kind of right and getting a bit long and |
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| 06:07 | there's a point where that becomes a to them do DNA replication and then |
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| 06:15 | out final revision. Right? So doesn't just keep growing and getting bigger |
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| 06:19 | bigger. The vestal point then Okay. And so it synthesizes its |
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| 06:26 | material like this and and patches all the length of the cells. So |
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| 06:32 | kind of elongates as it grows. . Um now other cells do it |
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| 06:39 | . So cox oid cell circular shell all this from the middle like |
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| 06:45 | Right? All that pink area is wall thicknesses are trying uh here is |
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| 06:50 | rod shaped cell. You see it all throughout the length of the |
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| 06:55 | Um Some types have what we call , you have a rod shaped |
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| 07:03 | two ends as polls. And polar means the growth is primarily occurring at |
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| 07:11 | end. Right? That's why you it only occurring here. Here's a |
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| 07:16 | shaped cell. Word occurs all throughout length. So you see differences like |
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| 07:22 | and what a difference like this down in polar growth translates into odd shaped |
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| 07:33 | . They don't tend not to be uniform in shape. They'll have like |
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| 07:38 | forms, may be what they call shape. So that kind of poor |
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| 07:43 | lends itself to that kind of type growth where it's not so uniform. |
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| 07:47 | show you a picture of this in little bit, but you can see |
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| 07:51 | themselves um in terms of their rod shaped cells that will elaborate on |
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| 07:57 | in a bit. But the point we're just kind of more focusing on |
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| 08:00 | , on the cell wall surfaces. . And whether it occurs at one |
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| 08:04 | mostly or in the middle of round or if it's all throughout. |
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| 08:09 | so they'll have variations like that. . And so and peptide synthesis itself |
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| 08:15 | kind of a complex thing. You the solo itself is a little bit |
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| 08:19 | . Multi two different types of components together. Peptide prosperous. So getting |
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| 08:25 | that going can be a involves a of components. Okay um any questions |
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| 08:32 | that? Getting more of general and not getting too specific here. But |
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| 08:38 | so we look at Let's look at question here. So this question um |
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| 08:46 | us to kind of the last part part one. So we're gonna look |
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| 08:49 | things like um uh types that don't follow the grand positive and negative |
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| 08:59 | Okay. As well as structures that maybe external to the salon and that's |
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| 09:07 | of over here to wrap up chapter one. Excuse me. That's kind |
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| 09:15 | what these terms are relating to. and michael plasma are two different |
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| 09:52 | Okay, and look different and are . They are precarious but they |
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| 10:00 | And in the spectrum. Okay. right. The time is going and |
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| 10:24 | is a true statement. There is true statement here. Okay, let's |
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| 10:42 | down from seven ship. Okay. an answer. D as in |
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| 10:59 | Why is it? He didn't? huh. Okay. Alright. So |
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| 11:15 | I saw all what kind of slim do so yeah I mean michael plans |
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| 11:24 | there's nothing there for penicillin to penicillin works on components of cell wall |
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| 11:31 | . So the other ones are all A. B. C. Um |
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| 11:38 | . Okay so that is and we're cover these uh terms right here. |
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| 11:45 | so you're a typical cell walls. archaea mycobacterium are examples of this um |
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| 11:55 | mentioned michael as well access so well mycoplasma are say uh you can cause |
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| 12:03 | type of pneumonia in humans and in one of the cells of the |
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| 12:09 | Uh the archaea Kia whereas among bacteria have a somewhere in between a few |
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| 12:26 | lack of soul wall. Your mycoplasma kind of spanned so some handles so |
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| 12:31 | and some don't um those that do called pseudo Myrie. Myrie in Alright |
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| 12:39 | this term here is an old term means people like you. I mean |
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| 12:47 | you know I mean it's just somewhat it but not quite. So there's |
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| 12:51 | very similar chemically to but there are some differences and so we call it |
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| 12:57 | Miriam michael bacteria. So those and couple examples are tuberculosis bacterium mycobacterium when |
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| 13:05 | comes to leprosy but there certainly are that this is basically it's a it's |
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| 13:10 | typically a soil microbe and um and are many species that are not pathogenic |
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| 13:18 | I usually put those as examples but people are familiar with the right that |
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| 13:23 | people are aware of. Mycobacterium flee which is a benign soil microbes. |
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| 13:28 | I try to give examples that you be aware of. Anyway so mycobacterium |
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| 13:36 | you know uh feature there are other that you might look at the growth |
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| 13:44 | a precarious solid medium or liquid and can look have an appearance that can |
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| 13:52 | you something about its structure. Mycobacterium is one of those so in |
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| 13:59 | medium. So on the left here uh this would be a for example |
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| 14:05 | E. Coli growing in okay uniform cloudiness and brought tragedy. It's basically |
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| 14:16 | solution. Okay um this michael bacteria very different. So it grows kind |
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| 14:23 | clumps together and grows on top of liquid or air liquid in your |
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| 14:28 | Okay on a plate solid media it this appearance here. If you were |
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| 14:34 | stick your wire loop in there. . It would kind of have like |
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| 14:39 | waxy kind of like a candle wax kind of a texture to it. |
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| 14:44 | um All both of these features are related to the nature of its cell |
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| 14:50 | . Okay so it has it does petrol light can that is minimal compared |
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| 15:00 | the amount of these other components. . Which make up the bulk of |
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| 15:05 | envelope particularly these. My colleague Right? And this is what really |
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| 15:13 | it this kind of waxy consistency. ? And it's very hydrophobic. So |
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| 15:19 | kind of that's what it sounds kind stick together as they grow and it |
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| 15:22 | of rest on top of the uh wrote me, okay, sometimes they |
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| 15:28 | kind of fall down and uh but kind of clump together for that |
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| 15:33 | So um it also is why for tuberculosis or treat because that wall or |
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| 15:46 | wall that envelope is very thick And it chemicals have a hard time |
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| 15:51 | through that. Okay, so treatment antibiotics is not always so easy. |
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| 15:57 | , I have to find the right of antibiotic that were able to penetrate |
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| 16:00 | layer. It's also why they grow slow because it takes time for these |
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| 16:07 | food they eat to pass through this thick envelope. Okay, so typically |
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| 16:12 | E coli grows really well without 1824 . Michael Karen takes about 48 hours |
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| 16:19 | get decent growth. It really relates kind of get a little bit slower |
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| 16:24 | these nutrients to diffuse into their Okay, so um now mm and |
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| 16:35 | acid fast. And so acid fast . So you don't really grant you |
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| 16:39 | a couple of like and they don't stay with the grandstand doesn't really penetrate |
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| 16:47 | properly stained. Okay, so you there's two ways you can use a |
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| 16:54 | that's super super concentrated um or you use the same guy at a lesser |
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| 17:01 | . But you use heat heat Okay. And uh asset fascinating. |
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| 17:11 | so they will stay in like kind pinkish is an asset fast positive |
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| 17:15 | Okay um anyway, so that you to develop that stain for forward is |
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| 17:21 | very thick envelope. They have. so um now the structures that are |
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| 17:28 | outside the envelope, everything is actually all three types at once right |
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| 17:34 | Right? The capsule um slime layer biofilm. Okay, so biofilm is |
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| 17:43 | course a let me just put all up here. I'll start with biofilm |
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| 17:48 | . Okay so biofilm, we're talking biofilms I think in as part of |
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| 17:55 | four. But anyway, so biofilms not number one, the bathroom is |
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| 18:01 | to the growth of a lot of . Millions of microbes to biofilm is |
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| 18:10 | a random association of cells that just together to form this super thick |
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| 18:17 | Okay. Far from that it's a a genetically programmed event. Pc specific |
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| 18:27 | informant. Some can't, it requires surface biofilms are all about the |
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| 18:34 | So it is important for that or like a pillai that allow for attachment |
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| 18:40 | the surface and then congregation themselves and together and there's chemical signals that were |
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| 18:49 | out to attract the members of the there. Um It's also a nutrients |
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| 18:55 | process. Right cells are gonna stick that surface and stay there and presumably |
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| 19:04 | to feed this entity this by a that result. Right? So it |
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| 19:10 | out as a two dimensional structure on surface. They can build up to |
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| 19:16 | of members of the population. So so again, not not just a |
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| 19:22 | thing, it is a program So biosphere itself. So the cells |
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| 19:35 | in the biofilm, part of the of forming the biofilm is getting themselves |
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| 19:40 | . Then that triggers a he needs make the biofilm material. It's |
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| 19:48 | it's sugar protein mixture. It's basically glue that holds everything together. |
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| 19:53 | So all of them will be embedded this by some on the surface internal |
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| 20:00 | have you. So the biofilm is collective effort from the cells in that |
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| 20:07 | is one cell that produces it and fits tightly around that cell. So |
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| 20:13 | a it's a it's a numbers due lots of cells capsule and finally are |
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| 20:19 | to making it absolutely wonderful. I uh I'm learning it's an individual cell |
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| 20:30 | . So the capsule you find in feature many passages. Okay. And |
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| 20:37 | back train the streptococcus pneumonia that causes are very thick axle formers. Um |
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| 20:47 | a very nice factor because so anything agreements factor enables it to cause |
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| 20:52 | So a capsule can basically cover the of the pathogen and in doing so |
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| 21:03 | antigens may have on the surface from immune system selves. So amuse themselves |
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| 21:08 | really recognize it and that because the can be covering it, covering those |
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| 21:14 | . Okay. And that's how a avoid certain degree. Um But it |
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| 21:21 | a gene encoded structure tightly bound to cell. Okay. Unlike a slime |
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| 21:28 | . So slime layer is uh more less a metabolic byproduct. Okay. |
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| 21:41 | can the growth of bacteria on certain , excess of certain nutrients, carbohydrates |
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| 21:49 | no form. Sorry, secrete a of these things that they don't use |
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| 21:54 | it ends up just kind of associating the cell much like you see |
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| 21:59 | Okay pen's not working. All Hold on so much. Like you |
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| 22:06 | in the middle of that cell in middle. So it's not really tightly |
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| 22:09 | . It's kind of just secreted hangs it. Okay now so it's not |
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| 22:15 | a meeting code of Okay now um can you know because it's it's covered |
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| 22:24 | it. It can give protection. it can make it sticky and attached |
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| 22:30 | things. Okay. It's kind of sometimes it may have a lot of |
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| 22:34 | sometimes. Maybe not so much. kind of a somewhat of a random |
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| 22:38 | . Okay, so that's kind of of think about a slam there compared |
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| 22:41 | like a capsule. Is that for the last question I was announcing |
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| 22:58 | capsule is not a bio phone a when you see a biofilm A you |
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| 23:05 | you think surfacing you think bazillions of because the capital by a phone is |
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| 23:10 | product of lots of cells capsules They're a product of one cell. |
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| 23:22 | . Okay, so um okay, that's basically some of the concluding |
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| 23:30 | Part one. Excuse me. So two, then we'll go into the |
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| 23:35 | of the cell and see what's going inside there. Okay, so we'll |
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| 23:41 | we have to start with a Uh huh. Okay. So this |
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| 23:49 | one of these, we just talked just talk just talk about that guy |
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| 23:55 | couple of slides ago. So see any need to make sense here. |
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| 24:10 | is a false answer there as So there is a false Okay, |
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| 25:23 | count down from 10. Okay. yeah, it's it's one of these |
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| 25:40 | so they do these three components um have similarities to uh acting micro tubules |
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| 25:51 | you see in eukaryotic sort of But it's not a they don't they |
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| 25:56 | generate the motion of the in a or archaea as we'll see later next |
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| 26:02 | . Uh Flagler motion in the bacterium like a propeller. Very different |
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| 26:10 | Uh Magellan is the component, not tubules. Uh A gentleman that you |
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| 26:16 | out like a sperm or something is of undulating. Like I would |
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| 26:20 | Motion is very different from what a cario does. Okay, so but |
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| 26:27 | a through e are all true. . And so we look at those |
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| 26:31 | . So and this is just for for comparative purposes. I'm not gonna |
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| 26:36 | you on Eukaryotic plato skeleton. But to show the complex, it's much |
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| 26:40 | complex in the pro cario there's multiple for the set of skeletons. Um |
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| 26:47 | organ elms make intermediate filaments. Uh tubules have functions in moving organelles, |
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| 26:56 | uh movement, um acting. There's functions, you know acting muscle |
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| 27:05 | Right? So lots of different options these things and highly organized. But |
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| 27:11 | were found to have some of these have proteins similar to these. |
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| 27:20 | But the primary function in precarious is somewhat in self shaped form. |
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| 27:29 | forming the sell more so maybe in so in um uh cell wall synthesis |
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| 27:38 | coordinating that with cell division. This process of cept ation that occurs |
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| 27:45 | the bacteria when they divided the binary . Right, bacteria and archaea. |
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| 27:50 | kind of these elements are kind of in a lot of that. |
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| 27:55 | And so these are discovered in mutants in this case M. R. |
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| 28:01 | . B. Where the silicon forces shape but mutants uh a lot of |
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| 28:13 | which is not normal for them. , so this tells us that it |
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| 28:16 | have some function in the shape of cell as well. Um And so |
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| 28:22 | three types we look at here, F. Tsz. Um So that's |
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| 28:28 | in all bacteria as much as right , as far as I know. |
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| 28:35 | It's it forms generally it's not in ring like this throughout the life of |
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| 28:43 | cell. It only forms rings when going to replicate. Okay and we'll |
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| 28:51 | how that works. Okay so it helps to it's in the middle of |
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| 28:55 | cell. Both rod shaped cells and caucus and other types, but it's |
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| 29:02 | the middle. Okay. And it's kind of orchestrates the cept ation of |
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| 29:08 | cell during division. Okay and so the rod shaped cells can have this |
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| 29:16 | . R. E. B. , we saw this earlier, it |
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| 29:19 | of visited helical pieces throughout the length sell building cell wall. Okay? |
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| 29:28 | when the cell is going to divide the F Tsz comes into play to |
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| 29:37 | the expectation of the cell in the of that rock. So F. |
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| 29:43 | always kind of plays that role right the middle of cell facilitate the cetacean |
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| 29:49 | . Okay? Um and then in these are what I call a common |
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| 29:56 | , sell. The other name for is vibrio. Okay, you may |
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| 30:02 | aware of uh cholera, bacterium, cholera. It is a common shaped |
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| 30:09 | and so it has all three So the F Tsz conform as the |
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| 30:16 | . E. R. B. a cell wall synthesis. And then |
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| 30:20 | has this piece here, it kind acts like a plate if you will |
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| 30:26 | one side of the cell anchored there gives it that kind of curve |
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| 30:34 | So the sentence is pretty much all giving that sell its curved shape. |
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| 30:41 | , so that's the example, that all all three types of the pseudo |
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| 30:47 | elements. Okay, the right shape two of these. Right and the |
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| 30:52 | one. So um so if you at expectation, right, so this |
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| 31:01 | of coordinates. So did it sell ? Um So uh so size will |
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| 31:15 | increase somewhat both in rod shaped cells in toxoid cells. Um and then |
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| 31:26 | begins to be a trigger for Okay, so preceding that will be |
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| 31:32 | a replication and then the the expectation of all this has to be |
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| 31:40 | Huh? Expectation excluding themselves occurring if DNA copies haven't been made in in |
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| 31:51 | now. Right, so all that some time. Right. And so |
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| 31:56 | um so cetacean basically occurs with this um complex called basically synthesize all the |
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| 32:09 | envelope material. Okay. And it kind of, it occurs from the |
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| 32:19 | the sides of the solar field. if you see here, it comes |
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| 32:25 | in this fashion here. Okay, the septum is finally completed and then |
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| 32:32 | have a splitting into two cells for . D. S. Z. |
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| 32:39 | that's that Z ring in the middle the cell. Okay. That acts |
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| 32:44 | a scaffold and then kind of constricts well. And synthesizing cell wall material |
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| 32:51 | the way I ran it. It's hard to kind of visualize this. |
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| 32:56 | , so I'm trying to find a of pictures online and I still couldn't |
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| 33:00 | find one that was ideal. But a couple of things, I'll show |
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| 33:04 | . And so this is um is again, don't need to write all |
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| 33:11 | stuff down. Okay, I'm just sure you this example. So there |
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| 33:14 | a lot of parts. So ftse one component. There's actually a number |
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| 33:17 | mps components that come together. And important to realize is this is an |
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| 33:24 | requiring process that we are making I we're making two cells were making synthesizing |
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| 33:31 | wall material. That's gonna take lots energy. Right? So you're gonna |
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| 33:34 | to have a source for that? this happens to show a gram |
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| 33:38 | Right? Because we have a but the process is very similar to |
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| 33:44 | positive as well. Okay, So have multiple components coming together. |
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| 33:50 | And um then, Okay, so uh have the segmentation process occurring |
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| 34:01 | So the F. T. Z. Ring. Okay. The |
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| 34:06 | of the preliminaries, the form of ring. Uh So, um so |
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| 34:18 | we go through the process, it's look something like this. Okay, |
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| 34:24 | , um so what you see All right, we have to do |
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| 34:31 | occurring. Talk about this in a , but down here. Right, |
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| 34:40 | , cool, polls cell not the of the cell. Right? So |
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| 34:46 | would be a new new a new is being made here and here. |
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| 34:54 | one. The old point because there's new material, that's what existed |
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| 35:01 | Right? We're making new stuff So to sell old and new. |
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| 35:07 | what that refers to split. That is new material. Okay. Out |
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| 35:14 | is old. Right? And so can play a part in um, |
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| 35:21 | certain cell behaviors if you will. , I'll get to that shortly. |
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| 35:26 | the point now is just kind of this happens, we have an old |
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| 35:30 | and we have a new poll. ? And this and the pool terminology |
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| 35:35 | specifically to rod shaped cells. basilica. And so, um, |
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| 35:45 | , there's nothing worth hair worth showing . Let's look at this. |
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| 35:50 | this is an illustration. Let me out of here. Yes, |
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| 35:55 | Okay. That's, I think this the most sense to me. |
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| 36:02 | so here is a, so it's patient process beginning here. So it's |
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| 36:10 | to be and meeting at both size in the middle. Um, precipitation |
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| 36:20 | occurred Into one cell here and sell . But again, it's that, |
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| 36:30 | , that did his own complex that's like this to create that new material |
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| 36:38 | that, in that septum. And so, um, as we |
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| 36:47 | up in these photographs right here. , here here. And so you |
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| 36:53 | , depending on how and so the at the arrangements of cox, I |
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| 36:58 | the staff load, which is like , like clusters, you can be |
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| 37:02 | toe difficult oxide or ted treads, is four sort of sinus eight. |
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| 37:10 | . So it's gonna be different And all these relate to what is |
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| 37:15 | plane of division. Right, are going like this then? We kind |
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| 37:20 | get streptococcus side. Are we like two planes and you can get different |
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| 37:26 | ? Are we in several planes that us the great black cluster? So |
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| 37:31 | kind of determines their morphology of of type in china. Um Okay any |
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| 37:39 | about that? Okay so um let's at this question. You may not |
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| 37:47 | all all of this yet but we're talk about it. So just do |
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| 37:51 | best best guess. So which bacteria going to be most susceptible to |
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| 37:59 | Right so we get basically you have two factors going on. Right growth |
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| 38:06 | . Does that play a part factor growing at all? Going slow and |
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| 38:14 | positive vs gram negative. So these factors can they play a part in |
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| 38:21 | susceptible it may be too in this penicillin. penicillin interferes with cell wall |
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| 38:32 | . Okay. Okay. Okay let's down from nine. Okay. Um |
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| 39:34 | answered B As in boy? Should 57 haben anybody gonna fess up |
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| 39:49 | You put your hand up gotcha. you answer be okay. Why'd you |
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| 39:54 | be give me your logic. All say that one more time. So |
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| 40:15 | was faster growth. That means they're more of what in terms of cell |
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| 40:22 | synthesis? More or less? This really growing fast culture. Really growing |
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| 40:28 | than a lot of selflessness is going . Or not Too much anybody. |
|
| 40:35 | of rapidly growing culture. Absolutely. . So the scenario is you look |
|
| 40:45 | it this way. Okay so a culture that's rapidly dividing cells, rapidly |
|
| 40:52 | lots of food and really grown like . We're looking at a microscope, |
|
| 40:57 | gonna see lots of forms like this the middle of divide. So something |
|
| 41:04 | this fast growing population. Right? means you know that's lots. We |
|
| 41:10 | saw right the uh what especially the shaped cellar, right? The |
|
| 41:14 | R. E. B. And on synthesis and then the F. |
|
| 41:18 | not there. Excuse me here at Z ring and a couple of synthesis |
|
| 41:25 | going on. Right, so lots on in this fast growing population compared |
|
| 41:30 | something like that. Slow growing Okay. Not as much. And |
|
| 41:36 | you have to think of in terms penicillin, right? In terms of |
|
| 41:41 | has which is the most important Right? So it's gonna be the |
|
| 41:46 | growing population more susceptible here. And that's not true. Just penicillin |
|
| 41:52 | for other certainly box as well kind growth dependent they work better when the |
|
| 41:58 | is more accurately for those antibiotics are present in those times. Okay. |
|
| 42:08 | now so you also didn't have the positive gram negative difference. Okay so |
|
| 42:18 | it turns out with penicillin, it's size of it. So much restricts |
|
| 42:23 | ability to get in through the korans of gram negative outer wall out |
|
| 42:31 | member. Excuse me remember the outer transport proteins? And penicillin can get |
|
| 42:37 | into some of those. But penicillin of big. Right? So it |
|
| 42:41 | really penetrate through the outer membrane very . So penicillins are always a good |
|
| 42:48 | for a for granted action. There other types of penicillin like drugs that |
|
| 42:56 | work because they tend to like uh who have the ability to get into |
|
| 43:04 | small and a little more effective there be more broad spectrum uh positive and |
|
| 43:15 | . Okay, so you're gonna see the differences between negative and positive very |
|
| 43:20 | with different treatments. Why you always both. Right for testing efficacy of |
|
| 43:25 | things. And so also um a there are antimicrobials you can use against |
|
| 43:35 | types. So in terms of like disinfectant, something like a what detergent |
|
| 43:44 | um antimicrobial detergent types resolved uh So that dependent on cell density, |
|
| 43:55 | ? Whether it's slow growing or still growing the membrane, it's |
|
| 44:00 | Whether the cells they're going fast or . The membrane is always a |
|
| 44:04 | And so those kind of antimicrobial agents well whether it's a slow growing faster |
|
| 44:11 | . Right? So for certain types antibiotics you have to kind of be |
|
| 44:15 | that they may have their differences. um many questions about that. So |
|
| 44:23 | the penicillin attack the end party. . Yeah. Um And we'll talk |
|
| 44:38 | about resistance and antibiotics and vaccines and later. But growing slow it can |
|
| 44:46 | be a strategy for some kind of as a way to counteract the effect |
|
| 44:51 | antibiotics. So they may sense that antibiotic um is starting. Not something |
|
| 45:00 | that but we've seen at the bacterial will just slow down growth because so |
|
| 45:06 | things an antibiotic it's not in your forever it goes away. And so |
|
| 45:13 | bacterial type will just just stop growing the presence of an antibiotic. And |
|
| 45:17 | when it dissipates goes down then they'll to grow again. That's actually a |
|
| 45:22 | to some use and uh yeah. because it's getting into the in the |
|
| 45:39 | of tuning out and remember to get it. That's the issue. |
|
| 45:45 | Yeah. You tell me you just through it. You tell me what |
|
| 45:55 | think. Mhm. What do you in these cells that you don't have |
|
| 46:08 | that? What's going on in these here? You what rapidly dividing? |
|
| 46:18 | also rapidly dividing. We just saw we have M. R. |
|
| 46:21 | B. Synthesizing cell wall material. have the ftse a lot more |
|
| 46:27 | We have we have rapidly a lot self acceptance going on that's what penicillin |
|
| 46:33 | target the enzymes that carry that If you have to sell us not |
|
| 46:37 | that at all. Or very minimal the fact that is not gonna be |
|
| 46:43 | so fast growing. It's not a for everything. But in this example |
|
| 46:49 | is, you know, um okay, so here's the question. |
|
| 46:58 | a before and after. Look at in a few slides down the |
|
| 47:06 | So basically just the terms Polly's own aging, reptiles, um, |
|
| 47:12 | transcription translation. Right? Bless Okay, let's count down from 12 |
|
| 48:28 | long. Fine. Alright. So answered? G. As in |
|
| 48:49 | G. It's uh 68 of Nobody. You're right. So I'm |
|
| 49:02 | desserts. Who's one of the 68 . So where did the two of |
|
| 49:07 | are thoughts? Well, she is . Right. So you got |
|
| 49:24 | You got it. Even though you see is correct actually. Um |
|
| 49:31 | anybody else? Yeah, it's And Yeah, B. And |
|
| 49:39 | Yeah. So it is B. E. Which means G. Is |
|
| 49:45 | . Okay, so, um, we'll go through these terms and processes |
|
| 49:51 | . Okay, um, nuclear So, so avoid from the |
|
| 50:01 | I. D. Like nucleus but it's not a nucleus, |
|
| 50:07 | It's a by the chromosome, And you can probably about none of |
|
| 50:16 | on the cell size. You're not see it with the scope you have |
|
| 50:20 | lab 1000 X. But maybe at . You might nonetheless, what you're |
|
| 50:26 | see is something like this area the more the lighter area, that's |
|
| 50:35 | area that occupied by the chromosome. . That's simply what we call the |
|
| 50:40 | oil. Right? That's it. ? There's not nothing membrane bound is |
|
| 50:46 | the area that the chromosome occupies in cytoplasm. Okay, so um important |
|
| 50:53 | this the story? Okay, so we look at cartoon here are Plays |
|
| 51:04 | important part. No one. It's replication begins the same as in your |
|
| 51:11 | . You have multiple stories in your but replication begins. But for the |
|
| 51:18 | it's also that also is a point attachment. Right? So also remember |
|
| 51:25 | in terms of replication vision of the , right? That the F Tsz |
|
| 51:30 | gonna be right there in the Alright. So remember that element, |
|
| 51:36 | ? That's part of the guiding expectation , putting the cells. Right? |
|
| 51:40 | the story is right there in the too. And it's attached on the |
|
| 51:44 | of the membrane because ultimately it's how that D. N. A. |
|
| 51:50 | copied, that the cell is able kind of hold on to it. |
|
| 51:55 | ? So when the story is which happens very early, it grabs |
|
| 52:00 | of both of those kind of pose in the cell. And but when |
|
| 52:05 | splits each half, which becomes each the whole cell gets a copy of |
|
| 52:12 | product, it's a way for it partition the copies accurately. Right? |
|
| 52:19 | doesn't have a psychotic spindle, Like right? To guide chromosomes to |
|
| 52:26 | poles, right? Doesn't have that need it. It's not that |
|
| 52:29 | So this is that that's its way kind of make sure copies go to |
|
| 52:35 | each each goes to a so Anyway, so just back briefly to |
|
| 52:42 | chromosome size. Okay so upper end has probably about four million base |
|
| 52:49 | So certainly we're talking about the order magnitude below what we've got. We've |
|
| 52:53 | a lot more DNA of course. part of the average value I'd say |
|
| 52:59 | million base pairs is probably the average for a pro carry a million base |
|
| 53:04 | . So it's small but still it to it has to compact itself to |
|
| 53:09 | into the small cell. Right? that's why it has lots of coiling |
|
| 53:15 | to kind of make it fit There will be different types of |
|
| 53:19 | what they call domains. Right? so parts of it are tightly wound |
|
| 53:24 | . Parts aren't right. It'll have binding proteins to kind of help stabilize |
|
| 53:30 | . A little little green spheres. so of course parts of it are |
|
| 53:36 | wound, parts are unwound because you different types of gene expression growing |
|
| 53:41 | D N A full of genes genes expressed and different genes are expressed at |
|
| 53:46 | times. So some parts will be up, Some parts will be unquote |
|
| 53:52 | and so forth and so forth. now the coiling. So the winds |
|
| 53:59 | unwinds the DNA gyre ace is there help help that with the coiling. |
|
| 54:06 | . it's a it's a dynamic molecules just sitting there doing nothing. There's |
|
| 54:11 | of bending and molecular binding and unbinding twisting and coiling and so on and |
|
| 54:17 | forth. Okay but you try to of keep hold of it right? |
|
| 54:21 | are points where it may attach Two the uh the membrane. Okay |
|
| 54:33 | kind of help stabilize it. So doesn't kind of something I wanted to |
|
| 54:38 | . Yeah hold on. Well that's what I wanted to try it |
|
| 54:44 | There we go. Okay so again little points of attachment to kind of |
|
| 54:51 | stabilize it. So it's not like around and get broken or anything like |
|
| 54:55 | . So um but anyway so that's of so as you go to another |
|
| 55:01 | of inside the cell is the transcription process. Okay so remember the chromosome |
|
| 55:10 | the nuclear Oid is the reason division transcription translation. Okay what happens in |
|
| 55:20 | ? We have transcription in the nucleus we have translations outside the nucleus and |
|
| 55:25 | site is all or no house in . Okay but bacteria don't have |
|
| 55:31 | Right. It all occurs virtually simultaneous translation together. Okay so cartoon here |
|
| 55:39 | course you see D. N. . Is the black thread blue. |
|
| 55:45 | the M. R. N. . Okay uh the gold these are |
|
| 55:52 | peptide strands. So we have R. N. A. |
|
| 55:57 | N. A. Right flow of and of course private zones right ribosomes |
|
| 56:04 | well. So remember the flow, central dogma, right DNA RNA |
|
| 56:10 | Right. So what's going on transcription, translation? So if you |
|
| 56:13 | at how it works in the pro , so copying a gene uh |
|
| 56:21 | R. And a copy of that transcription. Okay. And here's our |
|
| 56:27 | . R. N. A. we can label it if you recall |
|
| 56:31 | prime three prime. Right? So other part here and we'll talk about |
|
| 56:37 | later in chapter in unit three. . But for now I just say |
|
| 56:42 | M. R. N. At the five prime end among other |
|
| 56:46 | will have let's do it that are not worth our be using my |
|
| 57:03 | Yes it's kind of ugly there. about that. But very ugly. |
|
| 57:08 | see. Yeah. So it's gonna a ribbon zone binding site. RBS |
|
| 57:15 | binding site. Okay. The very of that of the market. |
|
| 57:22 | The only reason I pointed out is what our bibles I look for. |
|
| 57:26 | it sees it it binds. Okay it will then it will proceed to |
|
| 57:34 | um and begin to translate. And so it then moves and then |
|
| 57:43 | space becomes unoccupied as the rebels of sites free again and on arrival of |
|
| 57:48 | so we keep going keep going keep down because as the writer's own bias |
|
| 57:54 | begins to translate. It moves right moves in this In this |
|
| 58:02 | Okay I can't get my pen to . Anyway, I'm gonna move from |
|
| 58:05 | to right, right. five prime three prime. Uh and as it |
|
| 58:10 | , we form a protein. And of course we can see that |
|
| 58:18 | protein strand right, is getting Alright. Compared to here, we |
|
| 58:24 | started goodness. Okay, I gotta fix this issue. All right. |
|
| 58:31 | it started here. Okay. And almost done here. Alright, we're |
|
| 58:38 | finished protein synthesis. So this whole we term this is a paul is |
|
| 58:46 | policies own polly Robinson same thing. . It's just coming together multiple lives |
|
| 58:53 | on a transcript. And the implication this is lots of protein is made |
|
| 59:01 | it's making lots of that protein and quickly. Okay. Because Okay, |
|
| 59:10 | one of the many reasons I can so quick and adapt to their environment |
|
| 59:16 | a small genome small size uh to lots of proteins quickly because transcription translation |
|
| 59:25 | coupled like information. Um and and can as quickly as they can turn |
|
| 59:33 | on, you can turn it off efficient control Right? And so um |
|
| 59:41 | , efficiency, right? Only only jeans, you need not everything at |
|
| 59:45 | . Right? And do so very shut it off quickly and turn on |
|
| 59:49 | . So all these things are part why my hair grows so fast. |
|
| 59:56 | ? Um because we're gonna grow You need to make lots of proteins |
|
| 60:02 | do that. And to also control as well is very important. So |
|
| 60:07 | only thing I want to say about this here is signal recognition particle. |
|
| 60:13 | . Is um is if you look the diagram above. Okay here so |
|
| 60:23 | proteins made this up. Right. are meant to function in the side |
|
| 60:29 | saul cytoplasm. Right. Others are to work in the membrane outside the |
|
| 60:37 | . So it has to be a to shuffle these things and get them |
|
| 60:41 | where they're supposed to go ourselves. it through the er and the Golgi |
|
| 60:48 | and all that. Right. That's we traffic proteins in ourselves. Right |
|
| 60:52 | different ways. So bacteria uses this . R. P. All right |
|
| 60:57 | are proteins. These are proteins. annoying. These are proteins at um |
|
| 61:10 | um die the protein a signal that oh I'm a protein that's supposed to |
|
| 61:18 | outside or into the membrane and srp find it buying do it. |
|
| 61:29 | That are meant to be the membrane to their definition and the other ones |
|
| 61:34 | have and that's what they do. so it's a way to kind of |
|
| 61:40 | proteins with that's all I wanted to about that. Okay. Um many |
|
| 61:48 | about the party's own formation. So so I just do this in I'm |
|
| 61:56 | it's gonna be obvious to you number vision. Although the end the end |
|
| 62:02 | is the same as those visions of toast is genetically equivalent cells. |
|
| 62:07 | Parents sell daughter cells both genetically Um Vision is not mitosis. My |
|
| 62:16 | is not mitosis, mitosis is a specific process. Uh We all remember |
|
| 62:23 | pro fes meta phase Hannah phase street of spindle, the movement of multiple |
|
| 62:33 | etcetera. Right? Although the function ? Of the McCarrick spindle. And |
|
| 62:40 | the bacterial cell its way of doing , it's about you know, accurately |
|
| 62:45 | the D. N. A. then making sure it partitions right. |
|
| 62:49 | sell because that of course happens in as well. But it's a much |
|
| 62:54 | process because you're only dealing with two where you can be dealing with multiple |
|
| 63:01 | in eukaryotic cells. So you have have some way to orchestrate that. |
|
| 63:04 | that's what the antarctic phases are all . Right to generate uh equivalent |
|
| 63:12 | Dollar sales. Now, Makarios the is much much more rapid problems on |
|
| 63:18 | cells making two copies. And then by using the ori right, remember |
|
| 63:26 | ori is a part of this process it kind of helps it attached and |
|
| 63:32 | inside of the cell. That's how can kind of grab hold and keep |
|
| 63:35 | of it. So it's so gets copy of that. Okay. So |
|
| 63:39 | simpler. Not surprisingly it, time . The big difference. Right? |
|
| 63:45 | precarious can do this in 15, minutes. All right. Uh It |
|
| 63:52 | much longer and you carry out. . Although you know the fastest cells |
|
| 63:58 | we have our would have would have uh Right. And those early cell |
|
| 64:06 | from the zygote to was it the chiller? Gastro etcetera was early developmental |
|
| 64:13 | . The pretty quick there. But that is on the order of a |
|
| 64:17 | hours and still Okay back here, can do this in minutes. |
|
| 64:21 | Not all of them. Alright, probably an average 20 minutes to two |
|
| 64:26 | . It's kind of average an hour you're gonna give an average value. |
|
| 64:30 | certainly e coli can do it very . So, you know so fast |
|
| 64:34 | you can produce 20 generations In 6-8 . Right. How long does it |
|
| 64:40 | humans to produce? 20 generations, years. 400 years to 28 |
|
| 64:49 | Big difference. Right. Lots of in those eight hours. Okay so |
|
| 64:55 | and it all goes back to small , small chromosome transcription translation occur |
|
| 65:01 | Lots of proteins can be made very . Uh it all fits together. |
|
| 65:06 | , so replication. Um Okay and know you've got your replication intro bio |
|
| 65:13 | all the leading strand lagging strand. fragments. You remember that? All |
|
| 65:18 | nuts and bolts? I'm not doing of that. I'm just kind of |
|
| 65:22 | you a here's what's unique about precarious of situation. Okay so um story |
|
| 65:29 | course is common to any replication. and so that's where the strands are |
|
| 65:35 | apart. Okay so we create replication and each one there's a zone, |
|
| 65:44 | each four will have a replica. . And each ripple zone has to |
|
| 65:54 | . N. A polymerase, I'll P O. L. For |
|
| 65:57 | Okay, so one there and one , because we're copying each is copying |
|
| 66:03 | strength, right, beating the lagging being copied, okay, at each |
|
| 66:07 | . And so then what happened, course, gets copied first very |
|
| 66:14 | is are the or ease? so the story gets copied, right |
|
| 66:21 | of the ori right there. because that's what the cells kind of |
|
| 66:26 | of a better term, grab a lot of those glories and stick and |
|
| 66:29 | those together so we can hold on the copies. Okay, And so |
|
| 66:35 | direction of replication right from each right? Then it goes to a |
|
| 66:39 | sequence, or the repo zones that off, and we've got to |
|
| 66:44 | Right, so we look at it here. Okay, so here is |
|
| 66:51 | these are represented very quickly after you the the is the other one, |
|
| 67:01 | copy is attached as well near the of the set. Okay, so |
|
| 67:06 | looking ahead, alright, we're gonna that F. T. S. |
|
| 67:11 | . Ring is gonna form there right . So um so he's bi directional |
|
| 67:19 | , but get noticed before you get making two copies, it's like it's |
|
| 67:27 | playing chess and it's looking like four ahead. So before we finish that |
|
| 67:36 | next round. So this is going go to make two cells but now |
|
| 67:41 | already before it's even done that it's going towards gonna have to be a |
|
| 67:46 | cells. Right? So starting next education first ones even done yet. |
|
| 67:52 | , again, that's another reason why can grow so fast. Right? |
|
| 67:57 | this is occurring under optimal conditions that very rapidly. So then um so |
|
| 68:03 | here the blue blue things are get and right after that happens, we've |
|
| 68:11 | almost completed this kind of application. very quickly we're gonna have two cells |
|
| 68:17 | then very quickly four. Right, very back this this is this exponential |
|
| 68:23 | that occurs as we talk about on . Right? We're not going it's |
|
| 68:28 | one and two and three and four growth. It's like 248, 16 |
|
| 68:36 | 32. So we call a J curve. Right? Like that cell |
|
| 68:46 | over time. Okay, so rapid . And that's how we can do |
|
| 68:50 | . Right? Small chromosome copying the strand before the first copies. Even |
|
| 68:58 | very rapid and we can get a for that here in this. See |
|
| 69:07 | . Okay, so let's look this quick. So again, here's the |
|
| 69:16 | and the story is shown in She gets up a little bit. |
|
| 69:22 | so here is our copying the story then both are attached to the cell |
|
| 69:31 | forks and we have copying bi directional . Okay, the red red, |
|
| 69:39 | see there is the terminator sequence. where it will fall off. |
|
| 69:45 | And so um so here we go we start copying it's kinda slow. |
|
| 69:56 | here remember before you get finish this right to already begin the next |
|
| 70:12 | So you can see this is gonna the first round. Now we started |
|
| 70:18 | the next one, we're gonna have cells eventually. Okay, so it's |
|
| 70:23 | rapid. Okay, and so here go here. Okay, and now |
|
| 70:31 | have two copies and eventually expectation We have two cells and then uh |
|
| 70:40 | information and then boom very quickly we four cells here, pretty quick. |
|
| 70:44 | ? So very rapid, very rapid any questions about that. So um |
|
| 70:56 | polar agent. Okay, so let that's okay, so the ribbon |
|
| 71:03 | So the red and blue. So a cell divides, right, I |
|
| 71:05 | this out earlier, the cell it will come in having had if |
|
| 71:12 | see at the top right, one poll. No poll that divides |
|
| 71:18 | of course where the segmentation occurs, where the new polls are generated. |
|
| 71:25 | read our old cold blue areas on polls. Right? So as the |
|
| 71:32 | change to grow, you can So it's with, you know, |
|
| 71:37 | poles in them. Okay. And in any given population there will be |
|
| 71:42 | proportion of old. Okay, so does this mean? Well, it |
|
| 71:48 | out that this contributes especially when it's stress souls under stress the uh these |
|
| 71:58 | holes will accumulate these damaged proteins. ? So maybe do the stress whether |
|
| 72:04 | heat chemicals, antimicrobials causing stress that can then these misfolded nonfunctional approaches continue |
|
| 72:15 | accumulate in the older poles. Not necessarily knowing completely why this is |
|
| 72:22 | on, but it's what's been Okay. Now we can play a |
|
| 72:27 | in is of course in the death the cell damage cell death but also |
|
| 72:34 | um they've seen not in all species they've seen in some that have studied |
|
| 72:40 | the differences in polar age population can in some cases antibiotic effective antibiotics, |
|
| 72:50 | ? That someone older older poles that slower and they can be can be |
|
| 72:55 | resistant in some cases compared to those are faster growing. Um Then you |
|
| 72:59 | your book goes into into a study micro bacteria which has growth mostly at |
|
| 73:06 | pole right? Alternates back and forth us to grow from one pole old |
|
| 73:13 | and from a new poll and then versa. Right? It creates a |
|
| 73:19 | of different polar ages. Right? they have varying susceptibility to antibiotics. |
|
| 73:25 | it's it's a it's not completely understood it's something it's yet another factor contributing |
|
| 73:32 | antibiotic resistance. Right, so but from that um there are you know |
|
| 73:41 | a rod shaped cell and having you oh it's symmetrical, there can be |
|
| 73:53 | growth asymmetric phenomenon that occurred. And of those is the endospore formation. |
|
| 74:00 | talk about this later. But these at one pole or the other. |
|
| 74:07 | . Um As you see here, is the spore forming in the |
|
| 74:13 | Okay. At one pole. Um , some bacteria like bacteria uh theory |
|
| 74:22 | caused by uh species. Um The at primarily one poll only sort of |
|
| 74:31 | can lead to kind of these weird . And so you see kind of |
|
| 74:36 | irregular forms like these, what they club shapes, um branching forms. |
|
| 74:44 | often what they call irregular forms and what they use the term. Anything |
|
| 74:50 | the is a uniform, right? uh they're all right. This is |
|
| 75:00 | uniform. But isn't there will be forms uh within there. Okay. |
|
| 75:09 | And then this type is one that has developmental phenomenon at the pole whether |
|
| 75:17 | the stock. Okay, this is stock form here, right there and |
|
| 75:23 | the flagellum over here. So it between these two. So sometimes they |
|
| 75:29 | from the stock. Sometimes it forms the jello, what drives that is |
|
| 75:35 | conditions. So it's an aquatic And in areas where nutrient rich it'll |
|
| 75:42 | a stock and sit on a rock something stationary and just live in that |
|
| 75:49 | environment, neutron rich environment when it the well runs dry, no more |
|
| 75:54 | and it forms a gel um and elsewhere to find nutrients. So kind |
|
| 75:59 | differentiates between those two states. at the end, all these are |
|
| 76:03 | are just all examples of check back with a pole and different things can |
|
| 76:10 | depending on the species at one pole the other. Just examples of |
|
| 76:14 | Okay. Um any questions about Uh you know uh well, |
|
| 76:34 | Yeah. For formation. Okay, sorry. So this formation will see |
|
| 76:47 | it can occur actually occur at the of the cold cell. It can |
|
| 76:51 | actually in the middle of the It can occur between the middle and |
|
| 76:55 | can be also be swollen or So different sports but some certainly occur |
|
| 76:59 | the end. Um Both only occurring one pole, not not both. |
|
| 77:07 | it gives you that kind of weird . And the last one is this |
|
| 77:13 | occurring at one pole, but switching two different things that stop. Just |
|
| 77:18 | variations of what can happen in that , that's all. Um That's uh |
|
| 77:25 | stop there, folks, so Thanks. And uh we'll see you |
|
| 77:29 | |
|
