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00:09 Yeah. Okay. Okay testing. right. Yeah trusting trusting me believe

00:59 . Okay. What's up your? . They're uh welcome. So uh

01:09 a note of the session I. . Up there. If you've got

01:13 mobile app, remember that uh the turning trigger points don't count for

01:20 Um uh They can begin they begin week but I keep reminding you of

01:28 you about the um Uh and the the attendance thing clock starts next week

01:34 well. So I remember that starting week, it's like required 16 of

01:43 sessions that will follow starting for us Monday. So um the point you

01:51 on on turning point uh this So I uploaded the what we've done

01:57 this point and I'll do it again and so but next week those will

02:07 to those who disappear next week. because they don't count for anything and

02:11 for you to make sure that your is working, you see your points

02:15 and all that. Okay? Uh they'll go away and be replaced by

02:21 course what we accumulate starting on Okay, next monday. So um

02:28 right, so today we're gonna finish chapter one and do a little bit

02:33 like two slides worth of chapter two 3 sides of Chapter three. Um

02:39 to kind of set set up that chapter he goes on for through next

02:44 and maybe a little bit more of following week. Um Let's see So

02:52 send out another email reminder tomorrow uh friday luckily tomorrow uh things for this

03:00 that are do are the blackboard quiz tomorrow at noon And We'll Cover The

03:06 one Stuff. uh there will be on everything on Chapter one, but

03:11 will be a touch on A number things we talked about in Chapter

03:17 and again you have like um let's you thursday through sunday. Uh There's

03:25 think there's something like number of Like is that not a whole lot

03:30 questions on it? But it's uh have once you start at the client

03:34 you aren't familiar. I'm sure you are. But once you start the

03:38 , the clock starts ticking. But but you can't take it any

03:41 in the four days. And just you do start it, you gotta

03:44 it Within 30 minutes. Okay. Let's see. So, I think

03:52 any kind of syllabus question kind of for anything. Okay. All

03:58 Because everybody's gotten a clicker. Uh just a matter of reunion license or

04:04 or registering it. So remember to that. Okay. All right.

04:09 um we ended last time with the about my pet peeve question on on

04:17 correct use of the terms right and disinfection sterilization. Okay. Ah

04:25 We're going to cover that in check five again anyway, so um to

04:29 much more about that. Except the thing is that acceptance is about disinfection

04:35 is about um an acceptance that deals living tissue. Chemical um treatment too

04:43 microbes living tissue. Okay, disinfection inanimate objects. So disinfectants can be

04:50 strong in terms of concentration and the of treatment there because they're not touching

04:56 or other tissue. Um The and course sterilization is the ultimate. It's

05:03 destruction of all cells. And those viruses are down to zero.

05:11 nothing there. So with insects and and accept this disinfection. His problem

05:18 it's Subsys um was was first put by Lister. Okay. And that

05:28 the practice of handwashing really. How hand washing is in stopping the spread

05:33 infection. And to this day you I teach them pretty nursing microbiology course

05:40 the fall and there's a section we about, you know hospital acquired infections

05:48 ? Getting getting you go to the for whatever it is. Uh But

05:53 while you're there you get an infection some sort and they occur depending on

05:58 hospital can be yep 10% infections can due to those hospital acquired infections.

06:04 the number one thing to prevent that the source of those is or the

06:08 that work there nurses and whatnot that treating patients and and not either using

06:14 PPE and they should be or uh . Handwashing. It really reduces the

06:21 of transmission. And so we know of course. And um but you

06:28 it wasn't until Lister showed this in hospital setting. Um The this is

06:33 1860s we're talking. And so he the hospital he worked in where they

06:39 mothers were pregnant mothers gave birth birthing . It was split in 21 half

06:45 handled by midwives who would the help the birthing. And the other half

06:51 doctors and doctors, typically first second year residents. And so they're

06:56 , they're still teaching them okay. mode. Right? And so these

07:03 doctors would you know have to go the rounds and have to do their

07:06 and whatnot. And they come out the uh of course a lot of

07:10 to spend with cadavers, right, anatomy etcetera. So they would come

07:14 of the about out of the dagger full of, but you got something

07:20 , they go, oh okay, set to deliver a baby now,

07:24 . Of course, there's no anything to do. So women in the

07:29 instance of what's called child bed peripheral fever, fever, same thing

07:36 infection due to the handling of the during birthing and causing this infection.

07:41 so uh both mother and child was to being killed by this. And

07:47 um in a clinic where the midwives doing their thing, they did do

07:52 centric more sanitary procedures, handwashing and notice notice this and said, oh

07:58 let's do this over here. So have kind of controlled experiments to show

08:02 when the doctors began to do rigorous all the time before uh expecting mothers

08:09 birth incidences of this infection was way . Okay So began became a standard

08:18 not long after this. Okay And so Lister was disinfectants disinfectants to

08:27 surgical instruments um to reduce the levels infection. Um The antibiotics were aware

08:37 antibiotics. Obviously these are naturally They're kind of natural defenses for the

08:44 . Um There are some fungi that produce antibiotics as well. Um Certainly

08:51 is one of those mold which was by accident and here's a plate on

08:58 bacteria were grown. But over here where the mold plopped down on the

09:03 randomly. And you can see there's area around the mold where the no

09:08 is occurring because the penicillin being produced it diffuses into the order. And

09:13 bacteria that are susceptible to it will grow up near uh where it is

09:20 diffused into so that he knows that goes okay and there's something to this

09:25 course discovery soon since then many hundreds of different types of antibiotics. Okay

09:33 course we know about resistant types which very prevalent and are a problem.

09:39 constantly having to look for a different there are different antibiotics um either finding

09:45 or chemically modifying what we have to if we can improve their functions.

09:50 it is a real problem. And course discovery of viruses. Okay um

09:58 talk more about this in the next . But the term filtering agent.

10:04 These rats he discovered or they didn't what they were really until 30 years

10:10 . Looking at the this disease of called tobacco mosaic virus of tobacco

10:17 And infected plants had kind of this spotted lifted leaves, kind of decaying

10:25 brownish not green, brownish with these on them. And uh so of

10:31 germ theory of disease was known at time. So it's like okay some

10:36 of microbe that's causing this. So take the plant leaves, crush them

10:40 and see if we can make a and then kind of liquefy it and

10:44 put it through a filter. So the filter will trap to trap

10:48 microbes will take that material off the and we'll put it on the healthy

10:53 . And that pattern is a battle disease. Well that didn't happen when

10:57 did that. But what they did it was by accident or not,

11:01 took someone to look at that went to infiltrate, right? And they

11:06 apply that to healthy plants. Then saw this disease. And so they

11:10 doing something super tiny That could pass these pores and they didn't know what

11:15 make of that really. But it until about 30 years later development of

11:20 microscope and they actually see these and is actually tobacco mosaic virus that causes

11:26 disease right there. So then began whole study of water virus is all

11:31 . And how do we control So and antibiotics don't work against

11:37 Why don't antibiotics work against viruses? and retreat a viral infection typically?

11:48 the target for antibiotics? Which Yeah. Yeah but what's the target

12:05 the target if they're similar targets it matter what it's in. Right

12:13 Like I'm rocking nope. Sorry, membranes. Uh So does anybody know

12:23 penicillin acts on? Excellent in the wall material in bacteria. Inhibits cell

12:31 synthesis in bacteria. And so but you're kind of alluding to the targets

12:39 antibiotics are things like ribosomes that interfere perfect synthesis or cell wall synthesis.

12:46 penicillin, ampicillin. There's a lot antibiotics that ending killing these are all

12:52 . Different aspects of cell wall synthesis bacteria. Um So more for targets

13:01 like DNA replication. So again these things that aren't in viruses as you

13:06 . And so the virus is not be susceptible to these things. Okay

13:11 are antiviral drugs that have been developed target virus specific. Um uh targets

13:18 cyclo beer is used to treat Um and certain ones that treat the

13:24 AIDS virus. So they're they're not plentiful as antibiotics. But of course

13:30 other defense we have against viral infections what you should know this in the

13:37 of this pandemic vaccination vaccines or how think counteract viral infections. Um So

13:47 we'll talk more about controlling growth in five. But let's kind of segue

13:55 . Okay, so this is we're get now into assuming we kind of

14:00 this down into five concepts the material this tracker. So we touched on

14:05 last two here and uh it kind relates to ecology, metabolism classification of

14:14 . Okay, this this question asks the in the search for life on

14:21 , why scientists expect to find microbes than typical alien monsters. Okay,

14:29 all seen the stereotypical oh alien. dude with the those facial features.

14:37 if you're looking for we're looking for on mars, why would expect these

14:40 of creatures? Why look for 88 salt. Yeah, that's

14:54 That's right on the right track. they you so obviously thinking for life

14:59 mars, we're not talking about looking life. That's on a temper in

15:05 temperate climate. Right? So we're be looking at extremes like you said

15:09 conditions and there are extreme conditions on certainly. And so what lives in

15:16 areas are microbes? Right, so particular type of microbe that they might

15:23 looking for here fits into this Okay, so let's across.

15:29 And so what's if you recall what little trophy is. Okay.

15:38 let's throw this a trophic pro carry could possibly do, what could they

15:44 carbohydrates to co two and water oxidized . The ceo to water oxidizing ammonium

15:49 to night night tribe to the above correct. Um and I drew in

15:56 glucose over there as an example of carb o hydrate. That's an example

16:01 a fatty acid man. Um Let get this. Okay, now you

16:10 respond. So with the trough. so little trucks were um type of

16:20 discovered by the next guy we're going talk about. Yeah. See some

16:27 the features that little trucks have that very important. Mm hmm, mm

16:43 . No. Mhm. Like I , you can always two or three

16:55 are better. Maybe better than Like consult. Okay. If you're

17:05 sure, do answer just to make you check your clicker. Mhm.

17:17 . So the who answered who chose right to work state. Mhm.

17:33 . So they cannot use this. that one of those fundamental mhm metabolic

17:41 that I'm gonna get talked about very because I have another question before I

17:45 that. But still, if the are use inorganic sources of energy.

17:52 . Um they use that energy then do something else with, which is

17:58 important. Okay, let's go to next question here and I'll kind of

18:02 this all together. So we just little pitchers, inorganic materials for

18:06 Right? You can't give them things uh certain types of microbes that glucose

18:12 and hope they'll be able to use ? Okay, so what you might

18:16 you would do to grow them throw them is use something like

18:19 Okay, So one of the things can uses things like H two H

18:24 S, hydrogen. They can use can use they can use ammonium

18:34 Right. Different things like that as energy source. And so here we're

18:39 H2 s. Essential minerals. So of the things you have to have

18:45 things like different types of minerals, ? To grow through anything really.

18:50 And so we're going to provide the proper amount of oxygen temperature. Maybe

18:56 other things to help it grow. . But and then of course all

19:00 stuff gets dissolved in water. So you satisfied the water requirement,

19:04 there's something else that this thing needs wouldn't will not grow without.

19:14 cannot grow without it. Okay. so um here are some choices.

19:22 , what do you think? All . Of these? They would have

19:28 have they can't grow without it. , but keep in mind the little

20:23 . All right, Thank you. , Yeah, carbon dioxide.

20:40 so, Breaking down to the two metabolic types. You can put everything

20:48 on earth all cells are so what organisms in one of these two

20:57 Okay, it's all based on how use carbon. Okay, we're carbon

21:04 life. Right. And there's a why why why did you say?

21:09 the phrase mean? Carbon based Why are we Why is that so

21:16 ? Because carbon is the number one that will influence how much growth you

21:23 , how much biomass we call it . You're going to collect culture.

21:29 want to make sure that it it can grow to high density.

21:32 absolutely have to add carbon to Okay. So why is that so

21:38 ? What is it about carl? know you know this one of the

21:43 molecules in our in our systems harbor , lipids, Right, proteins.

21:54 are they all made of? A carbon base? Okay. A

22:01 skeleton is sometimes called, right, the base structure. Take that.

22:08 nitrogen and phosphorus. Now you're making . Okay. Um and uh nitrogen

22:17 Bosporus uh you can also make them acid. Just configured a little bit

22:23 . Okay, So, but carbon the baseball. It's the number one

22:27 that influences how much stuff an organism make. Okay, because that's what

22:33 build it molecules out of. biomolecules. So, um it's not

22:39 sole thing, but it's the number thing has the biggest influence.

22:43 The We'll look at in Chapter The four main elements C.

22:49 O. M. P. Right. Carbon hydrogen auction night.

22:53 is what this is the main comprised the atoms of biomolecules. Okay.

23:00 so now with oh it looks different of like a plant. Okay because

23:07 use SEO to write they fix you what they do. Okay. And

23:12 your familiarity uh with what we call . Right? So autotrophs and hetero

23:21 the two basic metabolic types on Right. Auto veteran. Okay.

23:29 ? Trophy nostrils. Yeah, you're times um A little trophy is not

23:36 trophy. Typically You can only get and c. 0. 2.

23:40 . Um Petra post used more complex materials like glucose like fats like

23:48 Right? Um This is and this how we get our carbon is how

23:55 get energy as well. Like a for one. Alright, so we

23:59 eat glucose. Break it down Take those carbon units and build bigger

24:06 . But breaking glucose down, we energy from that https so we the

24:14 serves a dual purpose for us. right. But for autotrophs it's

24:18 Okay, another trove. Has for . Little drove can break down H

24:25 s. But there's no There's no in this molecule. There's no

24:34 Right, so, I can get from something else. That's 26

24:39 So fixing the SOO two is no thing. Alright, to go from

24:45 to multiple steps to a complex organic like say glucose. Alright, C

24:52 H. 12 06. That's a bigger molecule. Right? You're taking

24:58 C. 02 with one carbon putting to make these big organic molecules that

25:04 a lot of energy. You got . Mhm. So if plant gets

25:08 from light, very light, it's photo water truth. That's the

25:14 Can break down in organic compounds to that energy to fix yo to write

25:21 called the chemo autotrophs. Chemo Okay, keep operative part of that

25:31 is autotrophs. Right? Ceo to SEO to head a trophy. If

25:36 don't do that, just think of , don't fix you too.

25:39 So um I know it sounds fairly but it You need to get that

25:47 since we get into Chapter four and and 13 and 14. Okay.

25:53 hear it? Time and again. these unusual metabolisms with the trophy um

26:02 able to use organic pom pom like wasn't known, believe before.

26:07 And so they were used to growing on bras and meat broths and stuff

26:12 this. Very rich organic materials. ? And so uh Gretzky was looked

26:19 soil, he kind of they call the father of soil microbiology.

26:24 Um it turns out that that kind microbiology is very important to us.

26:29 , these activities he sees in he saw in there he thought they

26:35 were a biotic not due to living , right? He uh inorganic compounds

26:41 utilized right? To do. He do analysis of the soil and you

26:45 see that transformations were occurring that are unusual. Okay like the oxidation of

26:51 compounds and fixing of C. And so he would take soil samples

26:56 go after question little things confidence or it just simply just chemistry no life

27:03 ? He would take soil and and right to kill. There's little things

27:08 there that would be killed by sterilizing soil and then compare it to.

27:12 that wasn't staring and see that the disappeared. The transformations he was saying

27:19 once he sterilized the soil because he killing the microbes in there. Doing

27:23 . Okay and so he set about kind of culture these things using what's

27:27 after Grodsky column. Using um uh you just throw together like mud.

27:37 particularly down into the wetlands environment. did this going over until there's a

27:41 , a little pond over there by just going on the shore line,

27:45 some of the mud, packing it a jar. What have you uh

27:52 things like newspaper that's carbon source right with the newspaper um costume sulfate calcium

28:01 so minerals can actually just add like to its shell and all to see

28:06 supply that and just put on the and the light hit it right that

28:11 several weeks let's see changes are visible a crime. And what's going on

28:18 um the appearance of these bacteria. capitalism is like sulfate reduction. Okay

28:27 these are types that can breathe, using these sulfur compounds like we use

28:33 in that water with us oh And convert that to H. Two

28:40 . Right. Sulfate reducing bacteria. are types that can take this and

28:45 oxidized that back to sulfate sulfate They can use Have different uses for

28:54 . two s. Like a plant water. Right? Fitzwater. You

29:00 look electronics to photosynthesize. There's bacterial that can use h. two

29:06 In a similar fashion its electrons that to save the sentences for it.

29:11 we now see photosynthetic types that are because you're really already is likely just

29:16 how plants do it. An Right? The same, right?

29:20 have the photo system 21 right in Z. Scheme and water is used

29:26 for moxie to write that. But know what you learned before. But

29:30 is a different type, right? , right? But a little bit

29:35 . Doesn't doesn't form oxygen. For , doesn't use his H two

29:39 Instead of water. Um And so see a combination of different bacteria in

29:45 at the very top right here are . These are bacterial types that photosynthesize

29:52 like a plan. So so you options out there at the top but

29:59 have none at the bottom so that gradient of oxygen hide below and so

30:08 here and low down here. And then you have different types of anaerobic

30:16 and just but again, all having different types of metabolisms that we haven't

30:22 before. Little tropes is what they . Okay. And so um the

30:30 the importance of this activity is what call thanking of elements. Right?

30:36 cycles. Okay. We'll talk about cycle in more detail later in the

30:42 . But for now the 43 sides represent different my criminal activities fixation.

30:49 little trophy identification. Okay, So nitrogen is about 79 but the atmosphere

30:59 into all. Right. And so but that's largely unavailable to things on

31:07 . Life can't use it as an source, but you're a climate that

31:13 fix it. Right? That's what nitrogen into the environment. Right?

31:20 it's aquatic or terrestrial. And so actually brings nitrogen into ecosystems. Okay

31:28 there's other types of notifications that Right? Those reforms. So life

31:35 things have different forms of elements. prefer. Some like ammonia, some

31:43 um nitrate nitrite. And so it these forms that they can access.

31:49 . Remember the points you need to proteins to make the cake acids.

31:55 . And so plants analogy um obviously oxygen to the Earth's environment right

32:02 Super important right there, ecosystems. plants and allergy uh challenging, you

32:08 , aquatic systems, plants and terrestrial or the foundation briefing system got to

32:14 them happy. Right? And they're . Might just give them some sunlight

32:17 some water and they're good to go see. Oh to which they can

32:21 from the atmosphere but they can't make essential mineral city nitrogen phosphorus there are

32:27 are often these are often limiting and nitrogen phosphorus and so bacterial activity of

32:33 cycle gives that to them. So why it's so critical to to life

32:39 on earth and not sure it's just . There's also phosphorus cycling phosphorus and

32:44 these other elements as well. So looked at the carbon cycling again back

32:51 the hetero probe probe. Right? so hera trophic activities like us,

32:58 release SEO to write as part of metabolism. Of course I'm supposed to

33:03 that. Okay, so it's constantly cycled back and forth. Uh

33:08 if we look at um ecosystems and importance of of these types of cycles

33:15 keeping producers happy. Right? So you look at a naive gone through

33:20 before last, the basic ecological trophic , food change that stuff.

33:25 So consumers are what here? Don't about the don't worry about the

33:34 Well, we'll just answer one of . So consumers are what? Okay

33:51 and producers different levels of consumers. it was like the composers in there

33:57 well. So among the composers, bacteria fungi, certain proto zones are

34:04 that group uh definitely important. They organic, dead organic material.

34:13 And that that to release of nutrients into the ecosystem for others to

34:17 Okay so yeah consumers are certainly hetero . Okay, producers are And so

34:26 the and so I mentioned that the . So if we keep producers happy

34:36 right, through these geochemical cycling activities then um just erase this producers are

34:48 Okay. So uh so think about if you restrict this vegan right,

34:58 eat meat at all. Okay obviously relying producers heavily. Right? So

35:03 want to keep it if you're strict , you don't eat plants at

35:09 Right? Just meet Well you also on this even producers happy as well

35:16 what the meat you read those animals producers. So it's directly indirectly.

35:22 all okay so um so again these cycling's occur primarily heavily driven by bacteria

35:33 here. Okay. Certainly nitrogen Pretty much all bacteria that do

35:39 Okay. Only um Okay and so those symbiosis, right, these are

35:47 symbiotic relationships. Um Endosymbiont CSR also more intimate between host and um the

35:58 is having a relationship with very intimate tissues. Let's say okay and so

36:04 microbiome. Alright, obviously closely associated you, it's on your menu.

36:09 um ruminants, cows, goats They have multiple digestive chambers.

36:17 So a cow grows really because of conversion of the materials eating grass,

36:28 ? Um by bacteria different types of in different chambers of its uh stomach

36:35 stomachs it has. And those bacteria uh the nutrients they can use to

36:42 feed and grow up. Um bacteria in those symbols. And so we

36:46 about actually fixation. So the ability bring nitrogen into the environment through a

36:54 bacteria and the biggest of that type activity is due to bacteria that have

37:01 with plants. So things like peanut plants, uh soybean plants,

37:11 foreign clover. These are all types plans to have these intimate associations with

37:17 in a species specific between the bacteria plants. Um The need to notice

37:24 what if you pull up a plant like this? You look at the

37:26 and little like knobby things and all roots and that's the nodules where these

37:30 living and supply fixed nitrogen supply it the plant. Uh And so very

37:39 . It uh it also allows has have this ability to have these

37:45 They can actually grow in kind of soil, nutrient poor soil because they

37:52 their own mechanism to to fix nitrogen to get nitrogen source or they can

37:59 like in sandy soils and things like that aren't very rich in nutrients but

38:03 can do it because they've got their personal way to get nitrogen to

38:07 Okay so uh normally you have to fertilizer to supplement the soils to grow

38:15 plants. So um now the trip far. So this goes into kind

38:23 classification a little bit. But there any question on we've gone through previously

38:29 at her clothes. That articles Nitrogen , you're gonna hear all that stuff

38:37 . Okay. In chapter um certainly 13 but some some something before.

38:44 Okay, a little bit about origins a whole lot of time on

38:47 But uh certainly it's thought that the micro fossil evidence Traces back live to

38:56 3.8 billion years, almost four billion ago. But there's still some argument

39:02 that really about if you look at micro fossil and you're trying to determine

39:07 there's a cellar there or not. can be kind of tricky.

39:12 so generally consensus is for sure two years ago. But I I'm pretty

39:19 it's much older than that. But um there's still a long time

39:23 right? They're prepared for the first on this planet. Um And you

39:29 look at micro fossil evidence like at top, especially this one here.

39:36 you can see it's kind of a look to it similar to what we

39:40 in some modern day bacteria here. , now one of the backup

39:47 So in early earth then we had not very much environment intact today.

39:54 , it was white um violent in of volcanic activity. Um temperature was

40:05 warmer. Typically there was no really to shield UV light from surface.

40:12 life evolved and what for that reason like can't penetrate the water very,

40:17 very well. And so in that uh actively supplying Sio two and

40:27 Uh many of of of reduced Okay and reduced meaning electron rich.

40:36 ? So for example, ammonia is more reduced than is night nitrite or

40:44 for example. Okay. And so are types of molecules that would have

40:49 around in the early earth. It have been used as a energy source

40:53 life. Right, So I thought that little trophic activity um and also

40:59 anaerobic. There's no oxygen yet. , so this is the kind of

41:03 you see in bacteria bacterial types and makes sense that they would have been

41:08 first one to evolve here. And so uh of course the evolution

41:18 or what brought option into. so they So this is the size

41:26 the plant. Okay, they have fields um They are actually the forerunners

41:31 the chloroplast as we'll see her But um obviously the inductions oxygen environment

41:40 effects. Right? You can create atmosphere uh ozone layers can help shield

41:46 UV light. Okay, so now can come out of water onto land

41:51 that kind of protection. Um oxygen metabolism can evolve. Right, so

41:58 using metabolism is much more energy. , so that means you care axles

42:03 bigger. Right? Eventually evolved into types. Right and so forth because

42:11 that type of metabolism. Because the energy you can sustain a larger body

42:16 you will. Okay so that was was hugely important. Okay um so

42:25 of endosymbiont endosymbiont again intimate association. evidence certainly suggests that eukaryotic cells evolved

42:38 what we call a proto three carry cell that would have evolved a symbiotic

42:48 with another bacterium. Okay so in we see a inspiring bacterium header trough

42:57 Okay and engulfed by a preview tear . And now that cell has a

43:07 to produce lots of a teepee engulfs than one of them because of symbiotic

43:12 eventually the the one that's engulfed right time loses a lot of its own

43:22 , write because it's inside that other cell now. Okay. And but

43:29 does remain our ability to respond? . So of course that becomes the

43:35 . Right? And uh in other . So this is actually a protozoan

43:41 pro Teesta. Right? Are kind the forerunners for the different kingdoms that

43:51 . Okay um those that also ingest develop a relationship with cyanobacteria.

44:00 That becomes a chloroplast. Right? a cell um forming in the symbiotic

44:06 with a core class. Now that become with the sign of bacteria that

44:10 become photosynthetic, you carry out an for example and then evolving later into

44:16 order plants and whatnot. So uh the evidence to support this right is

44:22 here. So Mondo condo and chloroplasts their own D. N.

44:27 Right? It makes sense that there to be a seller a long time

44:30 . Some of that's still hanging around . We're not talking about a whole

44:34 but parts of the D. A. And some of that is

44:38 to code for proteins that are used those organelles and even have some of

44:45 own ribosomes and T. RNA is there. Okay so it certainly suggests

44:50 an origin notes of that used to actually be a bacterial seller at some

44:55 before it became this endosymbiont relationship. Now on their own during my

45:02 I'm sure you know the eukaryotic cell sightseeing chromosomes replicating so to develop nails

45:12 and so mitochondria and chloroplasts can do but you can't take a a mitochondria

45:20 of cell which you can isolate that to do and hope it will grow

45:24 people look for something that won't happen ? There's too many functions are lost

45:28 that thing to actually be a right? Um Same with the floral

45:33 . You can take a class and on the Petri dish by itself and

45:36 will grow photosynthesize. Okay. But the within the cell itself as part

45:43 the periodic sell and and cell cycle can duplicate itself. Okay. Um

45:51 in looking at classification. Okay so kind of the hallmark for um classifying

46:06 nowadays of course it has been for few decades is comparison of nucleic acids

46:15 between between each nucleotide. It's really a point of comparison in fact.

46:25 if you look at a long stretch and then those are a lot of

46:29 lot of other similarities or differences. you can piece together how closely related

46:36 unrelated to organisms our or a group organisms. And so the molecule that's

46:43 becoming a standard for that developed probably 40 years ago now is 16

46:49 Or in it. But then, mean, the gene, so remember

46:53 not all jeans approaches, there's some the end product is RNA.

47:02 And so for my risotto RNA transfer . These are that's the end

47:10 Okay, so we're looking at the , the D. N. A

47:15 that codes for the 16 S. . Okay, that's what we use

47:18 comparison the so the S. Is a measure of mass. It's called

47:25 unit. Right? So bigger number a bigger molecule. Right, So

47:29 S. Is bigger than the five . 23 S. Is the

47:32 right? This is what the arrangement precarious. Right. Difference between

47:38 Eukaryotic ribosomes, appropriate rival zones are sizes of the RNA is,

47:45 So for example, the equivalent in is 18 S. Right? And

47:53 . And then there's Uh the other , a different one. But there

47:58 to a large and small subject. . And it's this one that's used

48:04 comparison making inferences about the negatives tree life and treat her is classifying all

48:13 using 16 S. RNA A. S. RNA. Okay. And

48:20 and it was chosen choice because of it's President present in every living

48:29 Okay. And um all molecules evolved time and they'll be mutation. All

48:38 that will occur all the time in jeans faster than others. Okay.

48:46 when of comparing genes for example in in organisms and the change occurs

48:55 Uh more changes occur over time then can represent a point of division.

49:01 ? Remember there? Two species form example? Okay so they're the same

49:07 same species but then changes occur in genes and then you see a split

49:11 ? They come to different that they two different species for example.

49:15 now the R. N. Molecules right cannot undergo a lot of

49:22 . Too much change affects the If you have a bad functioning rhyme

49:26 , you're not going to live because the only way to make proteins.

49:32 for that reason they call it a clock. It changes slowly over

49:37 So we can make inferences on relationships back right way back to my life

49:44 and um and using that technique, and Fox, Fox that Fox is

49:52 dr Fox George Fox in the department worked with woes back in the seventies

49:57 looked at this group of bacteria that these unusual um They grew they grew

50:05 unusual places. Right? Extreme extreme . Okay. And they began looking

50:12 Taxonomy and classification and they found that was actually two groups of precarious up

50:19 that point there was only they're only back precarious or only those bacteria and

50:23 it. They did these studies with 16 S. RNA molecule And founders

50:30 it was different enough you can see here there's 15 s. for a

50:35 bacteria E coli over here and Archaea here. So this is like a

50:40 dimensional Picture of 16 s. RNA and our uh unlike the D.

50:47 . A. R. Doubles training they can't fold on themselves.

50:50 It's just it's all about complimentary base . Okay and so the um the

51:00 arrow represents areas where there's where changes most likely to occur. Okay these

51:07 the areas they kind of look at when they compare them they saw there

51:13 actually very there was a significant difference two. That's what we need to

51:20 that there were two groups of protesters and bacteria. Um And so up

51:26 that point classification ended with the So you see kingdom phylum order class

51:34 genus species. Right. Kingdom. now their studies Real that there should

51:42 three domains. Right so three domains Kariya bacteria and archaea. Sorry and

51:50 microbes uh fit into ah of course and archaea are nothing but microbes.

51:58 . The among UK area bautista and contain microbes. Okay. Perotistas pretty

52:06 all microbes. Uh not all fun but you know yeast certain molds but

52:12 really no microbes as we define them kingdom animal and kingdom plant, plant

52:17 animal kingdom. Okay so um so you look at technomic history, no

52:25 microbes unlike us for example and other and other animals and so forth.

52:34 defined species by sexual reproduction. Can all members of the same species

52:42 reproduce outside their group? Right. how we kind of defined species when

52:46 go to bacteria for example that doesn't because there's no sexual reproduction going

52:51 It's all fine education. Okay so so we had we've had to look

52:57 you know really just the physiological characteristics bacteria and what they look like appearance

53:03 there. Their rods and arcoxia and their chains or they're not or they're

53:07 have this metabolic property. These kind things is what we used for a

53:11 time of course until we're able to D. N. A. As

53:15 comparison which is what's done. And and actually both both all the information

53:21 used not just DNA comparisons but also metabolic features and gram stain. Uh

53:30 shapes these kind of things But certainly standard is is looking at the

53:35 In the 16 s. RNA. uh kind of the criteria is if

53:42 have two species share Less than I'm , greater than or equal to 95%

53:48 then they can be called the But if they're more than that then

53:53 are two species. Okay. Um know in terms of history classified changed

54:02 time of course. But the number thing that led to the change and

54:08 microbes were continually group here and then were shipped grouped over here and then

54:12 and there. It was primarily driven what advances in what the most

54:20 We need to see him of microorganisms . So advances in my property or

54:26 really changed how they were classified as got better at being able to uh

54:31 see finer detail by by or increasing . Right? We can't differentiate a

54:39 career. Excel in eukaryotic cells. . But before then Let me things

54:43 classified as a plant or an That's it. Right there. Going

54:47 to the 1700s with remember that But then later on. And of

54:54 fungi and algae, algae understandably were in the plant kingdom. Being photosynthetic

55:01 . I'm not sure why that was guess they can't look somewhat like

55:05 Some of them uh and manera. so again this is what this is

55:12 there was for a long long time centuries. And then late 19th century

55:21 . He said okay let's take all microbes out of these kingdoms and put

55:28 memo on there. So when there nothing but microbes All right, protease

55:35 . Archaea all lumped in there. At some point I think in the

55:40 it was until the 60s when fungi taken out of the plant kingdom and

55:44 it into their own kingdom. Okay fungi have more in common with us

55:49 than anything else really. Um And . So in the manera then pro

55:56 so are eukaryotic cells. So that's change actually occurred once the electron microscope

56:04 developed because then obviously you have super are magnification. You can clearly see

56:10 nucleus and cells that didn't have a and etcetera. And so now we

56:14 differentiation to human proteins that so algae protozoa ones are in there and then

56:20 other group then what was left behind called the bacteria. The precarious.

56:25 so then of course is when it like this for um through the seventies

56:31 then uh then woes in the 16 . RNA. And then so we

56:36 the bacteria down into it is but bacteria in his kingdom. Archaea.

56:45 which then domain archaea and domain bacteria kind of silly when they still keep

56:49 that way but can you tell us but nevertheless two groups of appropriate

56:57 Archaea. Um And so the three right are you Kariya archaea and

57:08 And so uh so similarities. Okay make no mistake. Although archaea do

57:16 some similarity to you carry on themselves bacteria, don't they? They are

57:23 . They lack a nucleus. They organelles like materials have. Right?

57:27 they are certainly procuratorates like bacteria are they do have some components of

57:37 translation income with carry outs. Uh uh some of the components are little

57:46 . Some of the gene structures, you recall antron Exxon is how our

57:53 they have um some archaea have that well. Okay. The the um

58:03 sorry. So but again the point similar to the bacterial course is that

58:09 feature of no nucleus, right? complex organelles of course having similar diverse

58:16 like bacteria etcetera. Okay, so looking at genomes really just to say

58:24 uh but certainly for a pair of are very small. Single circular

58:30 For the most part, not that can be rapidly rapidly sequenced.

58:34 We do all sorts of manipulations with genes for various purposes, both for

58:43 basic knowledge, as well as commercial . Um and um the meta genomes

58:53 the ease of isolation allows us to find microbes, particularly bacteria and archaea

59:02 we wouldn't otherwise find because There's only 3-4000 Pro Coro seven catalog have been

59:14 , described and cataloged. Okay, the lab, But there's certain way

59:19 than 3-4,000. Right here. They're out there in the environment.

59:24 Thousands more and we'll be able to them. Not by culturing culturing them

59:29 we have been able to but because meta genomics. Alright so meta genomics

59:36 the code to to identify what you culture. Okay. And so and

59:42 represents a vast majority of them cannot cultured. So you have to rely

59:47 many genomics and what it basically is there's nothing um uh new really because

59:54 just it's the same techniques we've We know how to isolate DNA.

59:58 we take an environmental sample, the water, what have you? Almost

60:03 . And then you isolate the N. A. And then you

60:07 down the D. N. And the fragments and use the techniques

60:10 the common in DNA technology and cloning take those fragments isolated and put them

60:17 vectors that like to manipulate them and grow them up. Okay? And

60:22 put them in e. Coli as way to store them and usually collide

60:26 grow them for you replicate them for . And then you can then you

60:30 have a bank of cells each containing different part of the DNA. You've

60:35 from the environment. Okay? You sequence it and there's so much data

60:41 the internet. There's databases of all that have been sequenced and you can

60:46 it to what you guys say what's there is the same thing very similar

60:51 that's how you can begin to D. What you got. Okay

60:56 boy you can take the other track see okay maybe you're looking for a

61:00 protein function uh some sort. So can look at it from that aspect

61:06 terms of enzyme activity or what have . Okay so um but it's been

61:11 powerful tool because it has shown us not just identifying certain things you can't

61:17 but the numbers of different microbial types the environment right? You can take

61:22 handful of soil from whatever what's out and how much of what's the abundance

61:28 each type that's out there. And it changing over time? Right.

61:31 you can actually do ecological type of with factory in that way for decades

61:37 this was developed. What you did you took samples and you tried to

61:42 and culture everything. So and try make estimations of what's out there in

61:47 environment. Using that technique is not be very good. Exactly on the

61:51 . Everything. Right. This has really valuable in the land to establish

61:56 know get more accurate numbers of what's there and how they're changing and so

62:01 . Okay. Um So that's that's meta genomics does. It allows you

62:06 identify microbes that you can't co two the lab and isolate. Okay by

62:12 the techniques of of comment D. . A. Okay the. And

62:19 here we're just looking at this just representative types. Okay uh you know

62:25 you need to know here the basics you know the precarious their basic

62:32 Right? Uh bacteria Archaea. So are differences. So we look at

62:37 Kia and group you can walk them one of three categories. Right thermal

62:47 . Okay. They're often called extreme as you see there. Uh extremes

62:52 temperature certainly certainly Thermo files. They at temperatures above 50 uh typically but

62:59 you have your hyper thermal files. grow above 80 C. Okay now

63:06 archaea and bacterial types do live to in association with each other near each

63:15 . Okay. Um there are some properties That bacteria don't have for

63:24 Methanol genesis. So being a methanol producing methane gas. Ch four is

63:31 an archaea feature. Okay. Um four is a major greenhouse gas.

63:42 Worse than co. two before coming are bacteria that can actually eat methane

63:47 maybe so much balance it out. um it's a it's also a vigorously

63:55 process. Okay, occurs in the files. Extremes of salt concentration.

64:06 Upwards of can be upwards of 20% more. It's crazy. Okay you

64:12 this typically in uh where there taking for salt extraction. So you have

64:21 of seawater that water evaporates and it's concentrated. They're also naturally occurring areas

64:29 the red sea great salt lake there actually very sailing, very thoughtful.

64:35 so they'll grow in that um They have a very unusual okay, type

64:41 photosynthesis. We'll talk about that But that that does not use core

64:45 at all. It's a very different of process. Okay. But thorough

64:50 there are bacterial thorough files for But there's really not those that approached

64:55 hypothermia file range. Okay, um so the uh in terms of the

65:03 of a correlation between thermal files in and sulfur metabolism of different types.

65:09 if it reduces self the oxidizer and forth. Um the now among the

65:17 types of eukaryotes as mentioned fungi, moles, proto zones of pro proto

65:23 and allergy, different therapy, Right, so Petrova. Petrova.

65:28 . Allergy or photo autotrophs, proteins ahead of probes and then viruses,

65:34 talked about viruses, viruses, are different group? Right. We still

65:38 them microbes, but they're not. they're they're not cells that became replicated

65:44 host cells. So uh but then do groups to manage microbes.

65:50 so um any questions. So do know the main question I get with

65:59 one stuff is names, you hear hear these names? Ok, lots

66:03 names in the chapter one in the . Right, so just stick to

66:06 exam review. Should always examine, should tell exactly what to focus

66:11 Okay. But for us it's managed and coke and a couple of

66:16 Okay. Um Alright so let's just Talk a little about Chapter three

66:25 And um so here is all about the appropriate excel about structure or the

66:34 that's made makes up the cell um are the functions of those parts

66:40 Okay. And uh you know obviously you go through this uh look we're

66:45 about a bunch of different types of but no one bacterial cell or ko

66:51 has all these features of course. they all have different different of

66:56 And so one of the things I wanted to talk about because the bacterial

67:03 region beyond the pro curiosity, cytoplasmic differs. Okay, 10 different.

67:13 . And so I want to use term cell envelope to describe it.

67:18 . People get confused when you okay, what's the what's the cell

67:22 does the bacterium have? Okay. made of pepper look like can write

67:27 it can vary in thickness. Some don't have it at all. So

67:32 kind of make him a uniform. I used the term cell envelope.

67:37 , so what's what's the nature of bacterial cell, gram positive or something

67:41 ? Okay, so again the envelope is what's going on outside that inner

67:50 . Right here is the inner So for ourselves, the set of

67:56 membrane. Right. It's what bounds what makes a cell a cell

68:00 Right. It's what it's the boundary everything inside there is a cytoplasm.

68:05 , so for bacteria though, that can be more complicated about what's

68:11 on beyond that cytoplasmic membrane or in member. What's going on here?

68:16 the nature of that envelope? That's we call the envelope. What's out

68:20 ? Okay. Beyond that inner And they can vary as we'll

68:25 Okay, so for for this I constantly tell you to kind of self

68:32 yourself as you go along with the . It's very easy for chapter

68:36 You know, if you if you , you know uh the parts to

68:41 and whatnot, you can simply just a piece of paper out, do

68:43 and go, okay, there's the membrane. Uh let's see. It's

68:47 a gram negative. So that means got a kind of a thin so

68:52 then we have an outer membrane. ? You can label all this stuff

68:57 well, maybe it has a here's D. N. A. That's

68:59 a nuclear Oid. So again it's easy to self check yourself on

69:04 Okay. And I do recommended as way to, you know, you're

69:09 it, you know? Um So so let's look at this question

69:18 Okay so no back there. Okay take a look. Okay open

69:32 you can read through a little Okay so we're gonna touch on all

69:38 these and then some as we go here chapter this kind of stuff we

69:46 about up front Or in the part Posit posit 10 seconds. A little

71:07 . Keep going. 98, I . The little breaks. Mm

71:17 Okay, We're 21 pause. Okay. Let's see what we

71:29 Okay. Um if you answered uh you are correct. Okay.

71:40 all those 18 year old truth. . As we'll find out as we

71:44 through this. Um so, what wanted to do was just I'll come

71:49 to that later, but just kind give you the overview here of what

71:54 going to touch on in this Okay, so, as I mentioned

72:00 , we can find any self defined that set of plastic membrane or inner

72:05 would call it. That contains the of course. And so uh so

72:12 a membrane is comprised of fossil lipids and proteins. And we'll talk about

72:17 structure next time. But maintaining gradients learn is an important function.

72:24 Um if you uh if you had A and P going to actual potential

72:33 the sodium a sort of potassium And you know, how important gradients

72:37 across the membrane. Um so, the inner membrane. Okay, you

72:45 have of course, it balanced the with all different sides, uh water

72:50 course, most abundant um other et cetera then this area. So

72:56 area occupied by the chromosome. um it's not a membrane bound

73:05 Not like the nucleus is okay, not a nucleus. It's a nuclear

73:09 . Right? Um Nuclear order actually nucleus like Okay, but don't let

73:15 confuse you. It's simply the area by the chromosome chromosome just flopped out

73:20 the cytoplasm. That's all it And so the area occupied by the

73:23 the chromosomes, the nuclear. And under a microscope it will have kind

73:27 a grainy appearance. And you can of see oh there's nuclear. That's

73:31 simply it's just an area where the is not membrane. Can I?

73:36 of ribosomes are gonna be present. the number one. Probably the malfunction

73:41 any cells to make proteins. So not always gonna have a bunch of

73:44 zones. Then we can have this goes back to the term cell

73:51 . Right? So we have the membrane that what's beyond it. What's

73:55 out here? Right, well you have something like this right cell

73:59 right, pepper black and not like plant that has sailors. But this

74:03 different. Okay, it can be positive, very thick so on.

74:09 it can be Michael Graham which is type of oreo cookies, three

74:14 So all in the middle an outer beyond it. Okay um it can

74:22 plasmas which are small circular pieces of extra genes that can acquire this Through

74:31 mechanisms from other cells. Through conjugation . We'll talk about that unit.

74:36 . Okay, inclusions um this is of a generic term to describe.

74:43 kind of specialized structures typically can relate maybe a food storage molecule. It

74:49 be a maybe a metabolic type of to it. Okay. Um not

74:58 cells but to have them. Some some have certain types of structure.

75:03 it can be a number of different which will which we'll talk about as

75:07 go through this um external. Okay from very high pillowcases for attachment there

75:14 be motion of some type associated with as well. It can be used

75:20 um specialized pill. I can be to grab things from the environment and

75:25 it into the cell. Okay uh formal promotion. There can be different

75:31 that can be just one like There could be a a group at

75:36 end, it could be all around cells so they can vary. Okay

75:40 . So the problem blob shows up and so that is covering the entire

75:47 now. Okay, this is typical various factors. So various factors are

75:54 I mentioned now and again but certainly in the last unit which is about

75:59 microbiology. So the bureau's factor is structure that enables to sell to college

76:06 and clinical ones that are real violence are of the gel. Um a

76:14 . Okay. Among others. There certainly others as well. But definitely

76:19 these can often be virulence factors. , so um so that that's where

76:27 wanted to and focus any questions so pick it up next time and just

76:33 on with the cell structures and Um Don't forget backward quiz and smart

76:42 . Do sunday?

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