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00:00 Welcome folks. This is the uh lab. This cover is basically different

00:06 of growth of microbes specifically bacteria. of course is our focus in this

00:14 lab course. And so this is of those kind of introduction to how

00:20 will grow, how they grow on forms of media. Uh what we

00:26 solid media liquid. Um their their on those types of media. Um

00:34 are things that you'll encounter of course rest of the semester as we look

00:38 um and work with bacterial cultures in forms. And so its important excuse

00:45 to be familiar with these growth patterns you'll be using some of this knowledge

00:51 um when you're doing your unknown project in the semester uh particularly in terms

00:57 colleague morphology. Uh And so this is what's basically covered in exercise of

01:05 and 2-4. The 1st 12-1 is just to show you the that microbes

01:12 are everywhere, right? That's what means. And just basically a simple

01:18 and kind of allow you to visualize . And so I'll elaborate when we

01:26 there. But that's kind of what first lab is about your first exposure

01:29 microbes bacteria, how they grow in kind of thing. Okay so so

01:39 uh showing you that they're everywhere. you're gonna have a set of media

01:44 union group members will basically just inoculate to speak. These media with different

01:52 of environmental samples be there your own , you can cough on the plate

01:57 expose it to air uh swab the top and then put that material on

02:03 of the growth medium. All the and things will grow on these plates

02:08 to show you that they can't see with your naked eye of course but

02:13 there and they are everywhere. And it's the main reason why we have

02:19 which you will learn in the next lab to on aseptic technique why you

02:25 to do that because the microbes that that are in the air that are

02:30 the bench types that are on your . These are finger tips. These

02:33 all potential contaminants. And so you to work with them in a certain

02:38 . So you minimize contamination. That's aseptic technique is about. Which will

02:42 next week. So so we look growth of different types of media forms

02:49 can come uh solid media and this be in your typical Petri dish

02:55 We call them, they can be glass tubes which we call slants.

03:00 can be just in a tube or flask uh in a liquid form we

03:05 broth. Okay, so I'm gonna through this and you're gonna see examples

03:09 this in lab and be able to proper terminology for these. You

03:14 So again you basically just around everywhere what that means, right? So

03:17 everywhere, literally almost everywhere, both land and on sea in the

03:24 And uh you know, most things on in modern conditions on this

03:30 But certainly there are those that live the extremes whether it's very high temperature

03:35 you'll find in uh geysers in Yellowstone that creates natural hot springs uh to

03:44 cope uh Antarctica and uh several cold . They can live um extremes of

03:53 concentration, great salt lake, very salt concentrations. So uh that's a

04:00 osmotic challenge for those that are adapted those kinds of environments. Uh depths

04:06 ocean. These what we call barometric filic, they require these high pressures

04:11 get when you go deep in the um aerobic or anaerobic we call it

04:16 or without air without air anaerobic bacteria can live in these kind of

04:23 And there's certainly extremes of ph those can live in the city, very

04:27 conditions, some more basic. And you have microbes all over your body

04:33 in your body and of course are in every single place on earth.

04:37 are some areas that are inhabitable uh even in your body you wouldn't have

04:43 find them in like vital organs. say that was obvious obviously signal a

04:48 . So but you know, aside those examples, they certainly are all

04:55 the place. Okay, so um this fact that the bacteria everywhere as

05:02 mentioned are why you have to do simple technique. And so you're gonna

05:05 at um types. You'll find you for the examples you take the the

05:13 can certainly contain fungal spores that will on the plates and can produce their

05:17 of colonies. You're not gonna find the types of microbes and the examples

05:21 going to take in lab um you expect to find protozoan typically or things

05:28 algae typically. So but certainly is representative types of different types of

05:34 Okay. And of course there will a different types. Um They many

05:39 symbiotic relationships. You have symbiotic relationships your microbes. So they run the

05:45 of different types as as with all things. So um so what you

05:50 is you're going to work as a and you'll have six plates and you'll

05:56 two of these and use the sample your bench using cotton swabs that are

06:02 and sample an area on your bench apply it to your plate, incubate

06:07 at 37. Re centigrade one at . Okay. You see the difference

06:14 the growth there. The uh uh can certainly use your own imagination for

06:24 , plates four and six do do fingertips on plate five I guess usually

06:31 what you see on your on your but you can do the scalp and

06:36 if you wish. You can contemplate you want but you have the option

06:39 using your imagination A good a good is sampling your cell phone with a

06:44 and see what's on your cell That's always good. Um You know

06:48 reason to use your imagination. So then of course properly label your

06:54 Remember to label it. Always label plates. This goes for the entire

06:58 , label your plates on the don't label the lid, label the

07:02 of the plates. And then um know compare these results to the place

07:08 you're able have to control plates that inoculated and you can use that for

07:12 uh when exposed to air. And exposed plates should be Um uh exposed

07:19 quite a while like at least the length of the lab. So 45

07:25 60 minutes or more the longer the . And so to really get a

07:30 sample of of air particles that could on the plate. Okay so um

07:38 there's between incubating in 25 and Is your body temps? You would

07:42 organisms that live in around your body would that would be more suitable temperature

07:46 them to grow 25° are typically going be optimal growth for things that are

07:52 on your bench. Air contaminants. but you should see a difference

07:58 Um Culture bacteria. So this next basic coverage exercises 2-3 and 24.

08:07 so certainly with different media types you you can have liquid and solid.

08:12 can actually have something between a semi and so forth. And we'll see

08:16 of those during the semester. But liquid media you can do in different

08:22 of course from a list of small tube too. You know it's really

08:26 . And so in in industrial applications do use hundreds of leaders volume because

08:33 use liquid to get large mass A large amount of biomass to work

08:37 . So often times you grow cells you want something for them whether it's

08:41 . N. A. To sequence a protein they make or what have

08:45 . You you use liquid for that to grow cells to you know to

08:50 enough material to work with. Solid more for uh it's certainly critical to

08:56 pure culture depending on your culture because allows you to give a visual of

09:00 organism on a plate that you can with. Right? Certainly you can

09:04 at liquid under the microscope and see but you can't pick out individual cells

09:08 grow them. You have that's why need a plate. You sell lands

09:12 a plate and then as well isolated it will form a colony as you

09:18 here. Okay that represents that originated a single cell. So if you

09:22 them out you can see colony types represent a particular bacterial strain. Now

09:28 course that plate represents a pure culture it's it's all the same colony type

09:33 form and feature. And that's what look at. We're looking at a

09:37 on a solid medium like this. . And so but certainly liquid medium

09:44 be a part of your peer culture , but absolutely a solid medium plate

09:49 to has to be a part of . Okay. And so when you're

09:52 with the plates or liquids will have you're gonna be using aseptic technique and

09:56 , you'll learn that next week, it's to minimize contamination. So here

10:00 some images that show you growth on media, all of these. And

10:06 the bottom is broth media, you have slants as well. And there's

10:10 for each of these. Um You me on the plate will have a

10:14 form, right? Uh called How what's it look like raised up

10:21 the auger? Is it raised How does it look in the

10:25 You can see that here. Is it like convex or flat?

10:29 have you? Um uh raised, sorry, is both of these?

10:34 it raised? Flat? What have ? So it gives you kind of

10:38 examples there uh with the margin? the periphery, right? What's right

10:45 . Okay. Uh What's the form as smooth as it kind of

10:50 So there's there's terminology you use for . Um The and then the whole

10:58 . Right? So what's the whole look like we see here.

11:02 Uh Of course I would say the have around your regular filament is rise

11:08 . So just different terminology. So should be familiar with what terms go

11:13 which characteristic? Right. So convex the type of elevation, right?

11:18 smooth margin right around is the whole . So um so the terms used

11:24 the colony morphology when growing on a media on a plate. Um Now

11:31 can make really detailed observations of plates this right? By looking under the

11:38 microscope. So we put the plate , the light source shines through and

11:43 can make really nice determinations much like see here of the margin and so

11:48 . Okay, so you may find helpful. Uh So what you'll do

11:52 you'll have colony mythologies. Uh These will be plates available for you to

11:57 these observations. So mycobacterium has a appearance due to the nature. But

12:02 envelope is gives it a very unique on the plate. Um Kind of

12:09 consistency is a common soil microorganism. odor from soil. You can tell

12:17 readily. Bye bye. Yes. smelling the plate, you get the

12:22 on it kind of just slide it to your total knows you can that's

12:29 definite soil oder. Uh proteus have that you'll notice are spreading their not

12:37 very tight brown colonies for example, they're kind of it's very unique um

12:43 of morphology. It's really seen on place a serrations, the type that

12:47 of color pigment. So it's a sensitive mutation. So when it's growing

12:52 30 degrees, the pigment is expressed above the the enzyme is defective and

12:58 form the red color pigment. So you see it below 30 degrees of

13:02 , its reddish color. The seals also provide, provide a soil order

13:07 well as a common soil microorganism. It's an endospore former. So we'll

13:12 this one again in the gram stain you'll see endospore uh When you look

13:17 these cells, under the microscope is that produces a kind of a blue

13:23 tint to it due to these uh of these two uh pigments. And

13:29 that's uh very apparent on the Um Of course don't discard the place

13:34 going to be used by all the . Uh So slant. So slants

13:39 used typically for storage or microorganisms. when you work with bacteria, you

13:43 have a collection of them and you them and having them in tubes is

13:48 convenient because they don't take up much . And you can see there when

13:53 , when you inoculate a slant, not really for getting uh single colonies

13:58 you would with a round Petri dish . And so again, these are

14:01 storage, presumably they originate from a culture and you can just make a

14:06 on so to speak to get very growth. It's very good for showing

14:10 production and those that do that quite here. Um But again simply these

14:16 for storage not you're not gonna use slant for to obtain a pure culture

14:20 you can't really do the manipulations to isolated colonies. So as well it's

14:25 heavy growth. Okay, Purcell for , maintenance, maintenance. The liquid

14:32 aside from uh you know using liquid to grow lots of cells and and

14:38 them for various purposes. You can't look at the growth itself and I

14:42 tell you some things. Uh So can see here on this tube,

14:48 what we call uniform find turbidity. Probably just say this to a

14:53 just not as much growth, but that one is because you see a

14:59 cloudiness throughout the tube. These are more on the order of something that's

15:06 motel. So uniform financial ability is by motile organisms swimming throughout the

15:11 which is why they are suspended and throughout a very uniform consistency here.

15:17 growth kind of tends to fall to bottom because they're not motile and they

15:21 of just settle after a period of , which is why the broth appears

15:25 so cloudy to self settle out Okay um the um right here.

15:35 here example of mycobacterium and again that layer that they have around their cells

15:42 of makes the cells stick together and kind of just it's very hydrophobic.

15:46 they kind of tend to collect at air liquid interface. Like this very

15:51 that's called political formation. Okay. so those are the very strong

15:57 You're gonna see cultures of these in slants and liquid to liquid cultures and

16:02 and plates that colony morphology and and your observations. Okay so again uh

16:09 gonna see these throughout the semester. we'll have liquid cultures that you'll

16:12 you'll have played culture you'll use and prepare your own of the unknown.

16:18 um uh so good to be familiar growth characteristics and and the terminology used

16:24 characterize them. Okay. That's Thanks

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