| 00:00 | Welcome folks. This is the uh lab. This cover is basically different |
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| 00:06 | of growth of microbes specifically bacteria. of course is our focus in this |
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| 00:14 | lab course. And so this is of those kind of introduction to how |
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| 00:20 | will grow, how they grow on forms of media. Uh what we |
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| 00:26 | solid media liquid. Um their their on those types of media. Um |
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| 00:34 | are things that you'll encounter of course rest of the semester as we look |
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| 00:38 | um and work with bacterial cultures in forms. And so its important excuse |
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| 00:45 | to be familiar with these growth patterns you'll be using some of this knowledge |
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| 00:51 | um when you're doing your unknown project in the semester uh particularly in terms |
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| 00:57 | colleague morphology. Uh And so this is what's basically covered in exercise of |
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| 01:05 | and 2-4. The 1st 12-1 is just to show you the that microbes |
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| 01:12 | are everywhere, right? That's what means. And just basically a simple |
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| 01:18 | and kind of allow you to visualize . And so I'll elaborate when we |
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| 01:26 | there. But that's kind of what first lab is about your first exposure |
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| 01:29 | microbes bacteria, how they grow in kind of thing. Okay so so |
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| 01:39 | uh showing you that they're everywhere. you're gonna have a set of media |
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| 01:44 | union group members will basically just inoculate to speak. These media with different |
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| 01:52 | of environmental samples be there your own , you can cough on the plate |
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| 01:57 | expose it to air uh swab the top and then put that material on |
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| 02:03 | of the growth medium. All the and things will grow on these plates |
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| 02:08 | to show you that they can't see with your naked eye of course but |
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| 02:13 | there and they are everywhere. And it's the main reason why we have |
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| 02:19 | which you will learn in the next lab to on aseptic technique why you |
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| 02:25 | to do that because the microbes that that are in the air that are |
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| 02:30 | the bench types that are on your . These are finger tips. These |
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| 02:33 | all potential contaminants. And so you to work with them in a certain |
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| 02:38 | . So you minimize contamination. That's aseptic technique is about. Which will |
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| 02:42 | next week. So so we look growth of different types of media forms |
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| 02:49 | can come uh solid media and this be in your typical Petri dish |
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| 02:55 | We call them, they can be glass tubes which we call slants. |
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| 03:00 | can be just in a tube or flask uh in a liquid form we |
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| 03:05 | broth. Okay, so I'm gonna through this and you're gonna see examples |
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| 03:09 | this in lab and be able to proper terminology for these. You |
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| 03:14 | So again you basically just around everywhere what that means, right? So |
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| 03:17 | everywhere, literally almost everywhere, both land and on sea in the |
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| 03:24 | And uh you know, most things on in modern conditions on this |
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| 03:30 | But certainly there are those that live the extremes whether it's very high temperature |
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| 03:35 | you'll find in uh geysers in Yellowstone that creates natural hot springs uh to |
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| 03:44 | cope uh Antarctica and uh several cold . They can live um extremes of |
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| 03:53 | concentration, great salt lake, very salt concentrations. So uh that's a |
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| 04:00 | osmotic challenge for those that are adapted those kinds of environments. Uh depths |
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| 04:06 | ocean. These what we call barometric filic, they require these high pressures |
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| 04:11 | get when you go deep in the um aerobic or anaerobic we call it |
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| 04:16 | or without air without air anaerobic bacteria can live in these kind of |
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| 04:23 | And there's certainly extremes of ph those can live in the city, very |
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| 04:27 | conditions, some more basic. And you have microbes all over your body |
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| 04:33 | in your body and of course are in every single place on earth. |
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| 04:37 | are some areas that are inhabitable uh even in your body you wouldn't have |
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| 04:43 | find them in like vital organs. say that was obvious obviously signal a |
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| 04:48 | . So but you know, aside those examples, they certainly are all |
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| 04:55 | the place. Okay, so um this fact that the bacteria everywhere as |
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| 05:02 | mentioned are why you have to do simple technique. And so you're gonna |
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| 05:05 | at um types. You'll find you for the examples you take the the |
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| 05:13 | can certainly contain fungal spores that will on the plates and can produce their |
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| 05:17 | of colonies. You're not gonna find the types of microbes and the examples |
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| 05:21 | going to take in lab um you expect to find protozoan typically or things |
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| 05:28 | algae typically. So but certainly is representative types of different types of |
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| 05:34 | Okay. And of course there will a different types. Um They many |
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| 05:39 | symbiotic relationships. You have symbiotic relationships your microbes. So they run the |
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| 05:45 | of different types as as with all things. So um so what you |
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| 05:50 | is you're going to work as a and you'll have six plates and you'll |
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| 05:56 | two of these and use the sample your bench using cotton swabs that are |
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| 06:02 | and sample an area on your bench apply it to your plate, incubate |
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| 06:07 | at 37. Re centigrade one at . Okay. You see the difference |
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| 06:14 | the growth there. The uh uh can certainly use your own imagination for |
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| 06:24 | , plates four and six do do fingertips on plate five I guess usually |
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| 06:31 | what you see on your on your but you can do the scalp and |
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| 06:36 | if you wish. You can contemplate you want but you have the option |
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| 06:39 | using your imagination A good a good is sampling your cell phone with a |
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| 06:44 | and see what's on your cell That's always good. Um You know |
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| 06:48 | reason to use your imagination. So then of course properly label your |
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| 06:54 | Remember to label it. Always label plates. This goes for the entire |
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| 06:58 | , label your plates on the don't label the lid, label the |
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| 07:02 | of the plates. And then um know compare these results to the place |
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| 07:08 | you're able have to control plates that inoculated and you can use that for |
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| 07:12 | uh when exposed to air. And exposed plates should be Um uh exposed |
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| 07:19 | quite a while like at least the length of the lab. So 45 |
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| 07:25 | 60 minutes or more the longer the . And so to really get a |
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| 07:30 | sample of of air particles that could on the plate. Okay so um |
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| 07:38 | there's between incubating in 25 and Is your body temps? You would |
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| 07:42 | organisms that live in around your body would that would be more suitable temperature |
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| 07:46 | them to grow 25° are typically going be optimal growth for things that are |
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| 07:52 | on your bench. Air contaminants. but you should see a difference |
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| 07:58 | Um Culture bacteria. So this next basic coverage exercises 2-3 and 24. |
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| 08:07 | so certainly with different media types you you can have liquid and solid. |
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| 08:12 | can actually have something between a semi and so forth. And we'll see |
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| 08:16 | of those during the semester. But liquid media you can do in different |
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| 08:22 | of course from a list of small tube too. You know it's really |
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| 08:26 | . And so in in industrial applications do use hundreds of leaders volume because |
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| 08:33 | use liquid to get large mass A large amount of biomass to work |
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| 08:37 | . So often times you grow cells you want something for them whether it's |
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| 08:41 | . N. A. To sequence a protein they make or what have |
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| 08:45 | . You you use liquid for that to grow cells to you know to |
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| 08:50 | enough material to work with. Solid more for uh it's certainly critical to |
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| 08:56 | pure culture depending on your culture because allows you to give a visual of |
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| 09:00 | organism on a plate that you can with. Right? Certainly you can |
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| 09:04 | at liquid under the microscope and see but you can't pick out individual cells |
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| 09:08 | grow them. You have that's why need a plate. You sell lands |
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| 09:12 | a plate and then as well isolated it will form a colony as you |
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| 09:18 | here. Okay that represents that originated a single cell. So if you |
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| 09:22 | them out you can see colony types represent a particular bacterial strain. Now |
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| 09:28 | course that plate represents a pure culture it's it's all the same colony type |
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| 09:33 | form and feature. And that's what look at. We're looking at a |
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| 09:37 | on a solid medium like this. . And so but certainly liquid medium |
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| 09:44 | be a part of your peer culture , but absolutely a solid medium plate |
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| 09:49 | to has to be a part of . Okay. And so when you're |
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| 09:52 | with the plates or liquids will have you're gonna be using aseptic technique and |
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| 09:56 | , you'll learn that next week, it's to minimize contamination. So here |
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| 10:00 | some images that show you growth on media, all of these. And |
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| 10:06 | the bottom is broth media, you have slants as well. And there's |
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| 10:10 | for each of these. Um You me on the plate will have a |
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| 10:14 | form, right? Uh called How what's it look like raised up |
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| 10:21 | the auger? Is it raised How does it look in the |
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| 10:25 | You can see that here. Is it like convex or flat? |
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| 10:29 | have you? Um uh raised, sorry, is both of these? |
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| 10:34 | it raised? Flat? What have ? So it gives you kind of |
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| 10:38 | examples there uh with the margin? the periphery, right? What's right |
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| 10:45 | . Okay. Uh What's the form as smooth as it kind of |
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| 10:50 | So there's there's terminology you use for . Um The and then the whole |
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| 10:58 | . Right? So what's the whole look like we see here. |
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| 11:02 | Uh Of course I would say the have around your regular filament is rise |
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| 11:08 | . So just different terminology. So should be familiar with what terms go |
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| 11:13 | which characteristic? Right. So convex the type of elevation, right? |
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| 11:18 | smooth margin right around is the whole . So um so the terms used |
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| 11:24 | the colony morphology when growing on a media on a plate. Um Now |
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| 11:31 | can make really detailed observations of plates this right? By looking under the |
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| 11:38 | microscope. So we put the plate , the light source shines through and |
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| 11:43 | can make really nice determinations much like see here of the margin and so |
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| 11:48 | . Okay, so you may find helpful. Uh So what you'll do |
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| 11:52 | you'll have colony mythologies. Uh These will be plates available for you to |
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| 11:57 | these observations. So mycobacterium has a appearance due to the nature. But |
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| 12:02 | envelope is gives it a very unique on the plate. Um Kind of |
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| 12:09 | consistency is a common soil microorganism. odor from soil. You can tell |
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| 12:17 | readily. Bye bye. Yes. smelling the plate, you get the |
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| 12:22 | on it kind of just slide it to your total knows you can that's |
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| 12:29 | definite soil oder. Uh proteus have that you'll notice are spreading their not |
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| 12:37 | very tight brown colonies for example, they're kind of it's very unique um |
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| 12:43 | of morphology. It's really seen on place a serrations, the type that |
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| 12:47 | of color pigment. So it's a sensitive mutation. So when it's growing |
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| 12:52 | 30 degrees, the pigment is expressed above the the enzyme is defective and |
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| 12:58 | form the red color pigment. So you see it below 30 degrees of |
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| 13:02 | , its reddish color. The seals also provide, provide a soil order |
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| 13:07 | well as a common soil microorganism. It's an endospore former. So we'll |
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| 13:12 | this one again in the gram stain you'll see endospore uh When you look |
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| 13:17 | these cells, under the microscope is that produces a kind of a blue |
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| 13:23 | tint to it due to these uh of these two uh pigments. And |
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| 13:29 | that's uh very apparent on the Um Of course don't discard the place |
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| 13:34 | going to be used by all the . Uh So slant. So slants |
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| 13:39 | used typically for storage or microorganisms. when you work with bacteria, you |
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| 13:43 | have a collection of them and you them and having them in tubes is |
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| 13:48 | convenient because they don't take up much . And you can see there when |
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| 13:53 | , when you inoculate a slant, not really for getting uh single colonies |
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| 13:58 | you would with a round Petri dish . And so again, these are |
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| 14:01 | storage, presumably they originate from a culture and you can just make a |
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| 14:06 | on so to speak to get very growth. It's very good for showing |
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| 14:10 | production and those that do that quite here. Um But again simply these |
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| 14:16 | for storage not you're not gonna use slant for to obtain a pure culture |
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| 14:20 | you can't really do the manipulations to isolated colonies. So as well it's |
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| 14:25 | heavy growth. Okay, Purcell for , maintenance, maintenance. The liquid |
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| 14:32 | aside from uh you know using liquid to grow lots of cells and and |
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| 14:38 | them for various purposes. You can't look at the growth itself and I |
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| 14:42 | tell you some things. Uh So can see here on this tube, |
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| 14:48 | what we call uniform find turbidity. Probably just say this to a |
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| 14:53 | just not as much growth, but that one is because you see a |
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| 14:59 | cloudiness throughout the tube. These are more on the order of something that's |
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| 15:06 | motel. So uniform financial ability is by motile organisms swimming throughout the |
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| 15:11 | which is why they are suspended and throughout a very uniform consistency here. |
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| 15:17 | growth kind of tends to fall to bottom because they're not motile and they |
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| 15:21 | of just settle after a period of , which is why the broth appears |
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| 15:25 | so cloudy to self settle out Okay um the um right here. |
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| 15:35 | here example of mycobacterium and again that layer that they have around their cells |
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| 15:42 | of makes the cells stick together and kind of just it's very hydrophobic. |
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| 15:46 | they kind of tend to collect at air liquid interface. Like this very |
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| 15:51 | that's called political formation. Okay. so those are the very strong |
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| 15:57 | You're gonna see cultures of these in slants and liquid to liquid cultures and |
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| 16:02 | and plates that colony morphology and and your observations. Okay so again uh |
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| 16:09 | gonna see these throughout the semester. we'll have liquid cultures that you'll |
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| 16:12 | you'll have played culture you'll use and prepare your own of the unknown. |
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| 16:18 | um uh so good to be familiar growth characteristics and and the terminology used |
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| 16:24 | characterize them. Okay. That's Thanks |
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