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BIOL 2321_Microbiology for Science Majors - 2321_1_24_24_CH 1
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00:06 Mhm. And for now, hey , welcome. Uh welcome.
00:33 Um Thanks for braving the rain. thought it would be much worse than
00:40 . The weather would be much worse what's going on out there, but
00:42 it's more coming. Um So, so remember the the clickers, so
00:50 check canvas for your points? Um It's all gonna go away next
00:58 , right? The only reason they're posted is to make to give you
01:02 of mind that. Ok, I my app, I'm using it.
01:06 working. I'm seeing my points. good. Right? So when we
01:11 , uh when it starts for real , you know, you know,
01:13 system is working and you have no . So if you do have a
01:19 um functional point solutions app, And you've been answering questions if you're
01:27 zeros or dashes or nothing. then there is something going on right
01:33 . I can't fix it, but got to go to the quicker support
01:37 . Ok. Uh It's likely some of registration issue was usually boils down
01:42 , but so that's what this is . So making sure that, you
01:46 , it's working, right? Um, ok, so the next
01:54 , um, so Friday, so Friday we have the first of those
01:58 . It's really like, it's not it's like maybe six or seven questions
02:01 something. Um, the, but , you know, the clock starts
02:06 you begin. So if you start at one, you got to 130
02:10 can't, you can't save and come and do it on Sunday.
02:14 Um Smart work. The first of is due on Monday. Uh And
02:22 , so this week today, I we'll be able to finish up all
02:24 chapter one stuff um and start metabolism week. So heads up. Um
02:33 you, OK, when you, you look through chapter 13 and
02:38 maybe you've gone that far. Uh freak out because you're gonna see a
02:43 of uh metabolic pathways and equations and and that and the other.
02:50 Uh I'm not expecting you to memorize the steps of all these processes.
02:55 ? I teach it more knowing, the stages of the process, but
02:59 in what comes out kind of OK. If you look at the
03:02 notes, you kind of maybe have that. So don't be afraid that
03:08 my God, I have to memorize these pathways and all these enzymes,
03:13 ? So I have a way as do it uh that hopefully makes it
03:19 palatable for you. Uh But those you that have kind of a,
03:23 know, everybody has kind of some backgrounds in here that maybe you've already
03:26 organic chemistry. Right? Generally if do that, you kind of have
03:31 kind of through these things. So kind of do a little better,
03:33 you don't need to have that obviously. Ok. So anyway,
03:37 we'll, we'll get through it. , hopefully not too much,
03:41 stress. Ok. So, anything else, any other, any
03:49 , let me just ask a random . Anybody ever had an MRI?
03:54 long do you have to stay in thing? You remember the?
03:59 How long do you have to stay three minutes? Wow. Ok.
04:03 , I have to get MRI on knee tomorrow. So it's gonna be
04:06 he said, you're gonna be there 45 minutes. So, was it
04:08 at the 30 are you freaking out there a little bit or?
04:12 I thought I can see it How close is that thing to your
04:15 ? Pretty close? Oh, my . Ok. All right.
04:23 you did? Ok. Ok. , that's good. All right.
04:25 , ok, so, yeah, don't know this guy, I scheduled
04:28 with my doc. The doctor who the knee said, oh,
04:32 that guy likes to keep me here a long time. So, do
04:35 play music? Yeah. Yeah. . Good. So we'll see how
04:38 goes. Never had one of those . So um yeah, of
04:42 I'm gonna be at the age where things can be more frequent for
04:46 So anyway, ok, so we're start with a quicker question ends
04:51 So really the routine when we start time is like, ok,
04:56 here's a question about what we did time and a little bit of summary
05:01 the stuff we did last time, we'll dive into uh the next newer
05:06 . OK. So let's uh take look here. OK. So we
05:12 , excuse me, we covered uh of these things last time. Uh
05:16 see how we do here. Mhm. Mhm. Uh OK.
06:07 me a few seconds there. So uh count down from seven. Um
06:21 . Let's see here. Uh So . Yeah. So we went through
06:26 kind of the definition of a right? The microbe is so we
06:28 biofilms aren't, they're made up of of micros but, but, but
06:33 biofilm itself is not a microbe. . Uh I ka is not a
06:39 of eukaryote. It's a prokaryote. we have the IKEA and the
06:43 prokaryotes. OK. Uh mitochondria that thought to be a product, it
06:48 endosymbiont relationship, product of that, not between a virus and you carry
06:54 between a pro car out specifically a . OK? Um And then uh
07:06 Mora uh at one time, put algae, bacteria found together in this
07:12 group. That is true. Uh That was what's his name?
07:18 . Right. So the answer is microscopy. Uh And um uh Mora
07:25 then what happened was bacteria only left Mora pro pro and algae to
07:32 OK. Um Meic. So that's , doesn't involve culturing. OK.
07:40 using baby is setting all the DNA a environmental sample and then using for
07:45 DNA techniques to, to clone those and then using that to sequence and
07:52 that way. So it's, it's using cultures, it is how we
07:55 find things that are out there that not able to be cultured, which
07:58 basically most things, most micros. . And then uh spontaneous generation is
08:04 biogenesis. So, spontaneous generation is from non life. OK. So
08:12 , we'll talk a little bit about at the end of today in the
08:14 of um because obviously there was something happened four, almost 4 billion years
08:23 , right? Because there was no then. Now there is life,
08:27 ? So there was, we don't to that as spontaneous generation. That's
08:30 kind of a term that's kind of kind of negative maybe but use more
08:36 term. Um They actually used uh from an abiotic world to a bionic
08:43 . And there's a lot of work that a lot of work has been
08:45 in that area. Uh We haven't quite been able to do it yet
08:50 life from not life but lots of kind of experience around that.
08:54 so obviously, there had to be kind of event or than years ago
08:57 led to that evolution. OK. any case, um let's uh so
09:04 briefly. So we went through um of microbe, right? So remember
09:08 . So I always say, you , in terms of studying this
09:11 whatever you're studying this semester, for , what have you, it's to
09:15 of test yourself and, and think questions in your head to, to
09:21 that you kind of know this right? So a real basic question
09:25 be OK? I went through the on Monday and I think I got
09:30 pretty good grasp of it. You yourself, OK, if I had
09:33 draw a proc periodic cell and describe , could I granted I'm I'm not
09:38 this is super complicated, but it's way to check yourself. You go
09:41 . Well, let me just draw circle. For example, if you're
09:43 a rod shape, that's fine, , right? And keeping it real
09:47 at this point because we haven't learned about it. But you know that
09:50 going to be no, no right? There's gonna be um no
09:56 basically. OK? We know it's to be in a size range of
10:01 to 10 microns, right? So you can rattle those off,
10:03 bam, bam, you know that lets you know. Yeah.
10:07 I think I, I know obviously we're gonna build much more on
10:10 as we go through the semester. ? So these little self checks
10:15 I think a good thing to do , uh, you know, give
10:18 confidence about that, you know, material. Ok. And so,
10:23 , it becomes more important, certainly , um, as we get to
10:28 , maybe more complicated stuff, I to keep constantly checking yourself. You
10:32 know this might kind of fool myself then I'll give you a good test
10:37 China. Um All right. So so microbial definition, I need a
10:44 to see it. Uh They are microorganisms, they're sailor cells, although
10:49 is an exception of viruses which are cells. Um but uh you
10:53 cells can evolve change, they can in food, et cetera, they're
10:58 part of a tissue, right? aren't microbes. Uh they're not multicellular
11:03 that are super tiny, like they're biofilms, they're not a colony,
11:08 ? Biofilms are colonies represent lots of , right? So just make sure
11:12 keep these things in my, in size differences, right? 1 to
11:16 micron Os above that eres below that , OK. Um The uh you
11:26 , the basic differences between pro curs U kleos. Um the variations,
11:31 ? So we talked about just mentioned um um kind of the gray areas
11:38 you will maybe or, or some the anomalies, whatever word you want
11:41 use, uh you can have supersized typically due to their metabolism that either
11:49 fill up with water, perhaps in vacuum and get real big visible to
11:53 naked eye or another substance that increases size. Either typically how these kind
12:00 larger sizes occur. OK. So talk about biofilms, um colonies of
12:07 animals, tissues, organs. And so uh taxonomy. So we
12:13 at, OK. Here are the where they fit in, in,
12:16 the various categories of life, And uh they have a history as
12:22 . Remember, the history here is driven by advancements in the microscope,
12:27 better and better, being able to better. Rol. OK. And
12:32 um so initially everything animals and plants fit into, then pulled out into
12:39 and then from there and the prokaryote divide mona containers, prokaryotes and uh
12:47 and fungi and tearing the other, other microbes, the periodic microbes.
12:53 . Uh The symbion theory, uh origin of uh etic cells by symbiotic
13:00 with bacterial types, engulfing them. leading to the evolution of the
13:05 other to the chloroplast. OK. course, both coming respectively from a
13:10 of synthetic bacterium and one from atrophic . OK. And then uh uh
13:17 domains, right? So that was using the DNA sequence for the 16
13:23 homos RN A, right? Common all life. OK. And using
13:29 as a means of classifying organisms, ? So the domains are the three
13:33 taxonomic groups most inclusive. So uh car a pro um archia and
13:41 So the significance there for us is , is the discovery of two pro
13:47 groups like the bacteria and the OK. Um Meta genomics. So
13:55 know that um we can't culture stuff the lab. Uh Most of the
14:00 that are out in the environment, can't culture. OK. So we
14:05 know why because we don't know the feeding regimes if you will of all
14:12 microbes, because of all the interactions have with everything around them, like
14:16 microbes, um the the various nutrients and things are in the soil
14:22 water, whatever they're using sediment. we may not figure out everything that
14:27 require. So it can be very to grow a lot of these things
14:30 the lab. OK. Which is there's only been maybe three or 4000
14:36 at least have in catalog. So, but we found these other
14:40 through meta genomics. OK. So involves not having the culture rather
14:46 using DNA DNA comparisons to do And then uh we kind of end
14:51 with spontaneous generation. And so looking experiments to kind of refute,
14:58 This idea that life can come from these uh crazy notions of uh dirt
15:05 water coming together, rain and dirt give a price to frogs,
15:09 Or you have this recipe to make mouse, right? So these are
15:12 things that were disproven. Uh uh it took paste to do the um
15:21 , to establish that microbes, microbes not occur through spontaneous generation.
15:29 And so uh so the pasture, his thing was um establishing. So
15:37 a chemist, of course, you do chemical reactions and at at reactants
15:41 products thinking it was a completely that was completely abiotic, no biology
15:47 right? No cells at all. his work in fermentation production of wine
15:52 showed that growth of cells accompanied the of the end products, right?
15:59 , sugars, right, well then on by the yeast in this
16:05 And those yeast converted that to uh the absence of air, right?
16:10 to um ethanol. OK. And as he took samples, looking under
16:16 microscope, we saw more and more more and more ethanol being produced right
16:22 , what you may not have known we know now is that with
16:25 um the end products actually can inhibit because they're typically acidic. Um or
16:32 uh these are organic organic acids, alcohol, small molecules and um those
16:39 be inhibitory. OK. So you do have a ceiling at which they
16:43 and then the end products kind of them. But I think I mentioned
16:46 time about uh nowadays we have all of specialized strains we can engineer and
16:51 have acid tolerant, more acid tolerant that can give you wine that could
16:56 upwards of 18% alcohol. Right. . So it's not for you
17:01 OK? Um And uh the, , you know the here we're talking
17:06 maybe eight or 9% alcohol with the . OK. So uh in any
17:10 , his contribution was OK? This what you do in the process.
17:15 off kind of off tasting wine you on occasion is due to contamination,
17:22 contamination. OK? Because uh you you can ferment ethanol,
17:28 ethanol, but bacteria can ferment as found out all kinds of things and
17:33 kinds of end products with sugars. ? Uh A variety of different um
17:39 and alcohols. Uh He could um differentiate between specific bacterial species and the
17:48 products they produced. All right. so uh so the the the big
17:53 here was this conversion of organic material microbes by cells, right?
18:00 it's biological. OK. And um uh germ theory, fermentation really just
18:08 it's microbes that are carrying out these , right? Producing various end products
18:14 seeing that there was a growth in numbers correlated to an increase in products
18:19 formed and reactants going away. So um now, OK. Now
18:27 get into uh the next part here , and it's not directly um it's
18:36 directly attributable to pasture. His contribution this work was the idea of this
18:42 conversion of by microbes to products, ? So before we dive into
18:50 let's look at this question here. . So which statement is true?
18:57 this is one of those um I these here and there uh during the
19:03 called before and after. OK. we may not s uh we will
19:09 have seen, let me uh increase again. We will not have s
19:13 covered this yet. We're gonna cover now. But let's see.
19:17 let's see how you do and then see the same question in a little
19:21 and we'll see how we uh improve . OK. So I was reading
19:43 any questions or anything so far, questions? Ok. All right.
19:59 . We pause it there a little of reading to do and it is
20:06 fine to uh collaborate on these You know, two heads are better
20:12 one, right? Maybe three heads better than one, right?
20:16 uh, absolutely do that. That's . Just don't talk about, you
20:20 , the game coming up on Sunday something like that, right. Ravens
20:24 the Chiefs. Ok. Give it science. Ok. Yeah.
20:38 I'm gonna count down from 18. ? Ok. Check. All
21:01 Uh Let me just like a snapshot quick. Hm. Shot. All
21:13 . Let's uh, move on and , we'll revisit this and we're gonna
21:19 each of these A through F as go through. OK. All
21:23 Uh OK. So to finish up uh thing on spontaneous generation,
21:30 So pasture. So remember that the for this was, of course,
21:35 have inanimate nonliving material. Step step two was providing air,
21:41 They call it the vital force. . Yeah, those two ingredients and
21:46 gonna get life, OK? And pure he goes OK. Um I'll
21:52 a growth vessel that can meet that . OK? Actually, it's so
21:59 but ingenious. OK. So he uh maybe a medium, I don't
22:04 he, I know he was a blower as well, but maybe he
22:07 a friend to do this. But any case, the typical growth vessel
22:12 see there, but it has this as this swan neck, OK.
22:17 to the air. And so contaminants arise that would arise would you know
22:24 float on air particles, uh dust uh pet dander, these kinds of
22:29 . OK. And of course, can fall due to gravity,
22:34 So if you have to open the , you know, the the particles
22:39 just fall by gravity to the to little crook, the crook in the
22:43 neck. OK? And as long you didn't disturb the liquid um or
22:50 the top of the thing off to it to air, it was
22:54 OK. So when you, when would either tip it, get liquid
22:58 there or you could just even just the top of this off, then
23:04 would be in there and they would OK. And I don't know if
23:08 is true, but it's, it's that he's, there are still flasks
23:12 this that he made like in the seventies or something that are still on
23:17 , in his lab that they still free from contamination, right?
23:23 Anyway, but um so in a way to say, OK, well
23:29 to air and our, and we this bronze which we boiled,
23:33 But it's in our, it's, not living stuff and we have air
23:37 we're not getting any micro. So that kind of said,
23:41 you got us, right? And , you know, this thing of
23:46 , relates to, if you, know, this week you're doing a
23:50 uh where you have the plates and exposing it to air and you put
23:53 fingerprints on it and you maybe you on it, uh maybe you swab
23:57 cell phone on it, right? do you see what that looks
24:00 Right. Um And stuff's gonna grow , right? Because they're everywhere,
24:05 ? It's why that you'll start learning week in a lab to do a
24:09 technique, right? Because you want do your work. Um such that
24:13 only working with the strain, you interested in studying and not getting other
24:19 in there. Because, you it's there in the air, on
24:22 , on the surface, on your , right? So you have to
24:25 with it in a way to minimize . That's what the aseptic technique is
24:29 about. Ok. And so this of pasture this, but the pasture
24:34 was really kind of that, you , that they are everywhere and you
24:37 find it's not arising from nothing. only comes from life, right?
24:43 so it's only when microbes accidentally get the liquid that that's been boiled to
24:49 everything that they, that you get wrong because those cells give rise to
24:52 cells. OK? Now, having that um there is some things that
25:02 be a little bit inconsistent, let's , OK, so Kindle was a
25:07 who basically was reproducing his experiments that that pasture did and he and he
25:13 he was able to do that. occasionally he saw this phenomenon where um
25:20 was there would be growth uh fall and you had the swan neck swan
25:25 there and and you would occasionally get occurring. OK? And that was
25:32 to be due to these guys, ? We'll talk about endospore forming types
25:37 chapter four, I think uh in next unit. But this is
25:44 this is really why you have to an auto acclaim or to sterilize
25:48 That's what we do in lab sterilized because of these guys, right.
25:52 the endospore, all kinds of spores the natural world, right? There's
25:57 spores, there's um uh cysts which a type of spore that protozoans can
26:05 . Um There's uh and that's what are, are kind of dormant
26:08 And so there's all types of these of these in the natural world.
26:13 . But the endospore is super right? Because it's the most resistant
26:19 of any of these things. They've they've um been able to
26:24 So think of these as a right? And so if you plant
26:28 seed and add water, it will into a plant, right? So
26:31 under favorable conditions, the score, score here is the it was so
26:38 little circles you see in the OK. So these are all in
26:42 process of forming a spore here is you see free end those spores,
26:48 ? Don't worry about this. Now come later but, but it says
26:52 end those spores that are super resistant they've recovered those from, from from
26:57 million year old fossils that have revived right, to germinate. So very
27:03 and uh can remain viable for a time centuries, right? Um So
27:11 resistant to chemicals to temperature. And uh so if you have that,
27:17 apparently had these in some samples of broth and occasionally they would grow.
27:20 the spores would be able to be to the boiling. Then it,
27:24 it cools down favorable temperature and now can begin to grow. Right?
27:30 , really, it's the at right? Where you boil it,
27:34 at rest the germ, the spore germinates and produces goes into the cell
27:42 . OK. Sport. So, . So that germination process,
27:48 So in the boiling phase, the is present or resistant to heat,
27:53 cools down and they go, oh is favorable. Now, I'll start
27:56 germinate. OK. Now, this is they don't all, they don't
28:02 germinate at once, right? it's, it's some of them
28:06 OK? Others stay in the indo form, right? So the ones
28:11 germinate will be killed by the subsequent , the ones staying in the indoor
28:15 form aren't, but then you let rest, then you boil again.
28:21 eventually, if you keep repeating that eventually get all of the end,
28:25 forces will have germinated and then be by the boiling. That's why you
28:29 to repeat it. Right. it would be easy if they all
28:33 at one time, then boom, them done, right? But they
28:36 all work on the same clock. why you have to keep repeating the
28:41 . Oil cool. B of nowadays, you don't have to do
28:44 at all because we have an auto , right? We have a,
28:47 can create steam under pressure which produces high temperatures, right? And kind
28:51 a, a moist heat that penetrates spore. So we can kill in
28:55 spores in 15 minutes in an autoclave less. Ok. But back then
28:59 didn't have that. So you had kind of do this process.
29:02 Any question about that? Ok. Yeah, we'll talk more about in
29:07 sport types in, in chapter But this is kind of, you
29:11 , this is part of the process , you know, discovering microbes and
29:14 types of what they can do. . And among your endos sport
29:20 um there's only really two bacterial groups do this and one of them is
29:26 it has a lot of uh disease types. Uh tetanus is one of
29:31 types. That is that OK. All right. So back to this
29:37 of of pastures uh germ the fermentation uh that microbes could transform organic materials
29:49 end products, right? Sugars to , for example. OK. Now
29:56 that idea and go OK, in context of human disease. OK.
30:03 these bodies are organic material, So could it be possible that a
30:10 might transform a human body into a state? OK. And so that
30:18 of began studies into that, but , that doesn't mean that pasture during
30:25 fermentation is how we figured out No. OK. But it's the
30:30 of that concept of microbes transforming organic into other things, is kind of
30:36 carry over here. OK. So was Coke that established the, that
30:42 can cause certain diseases and how to that. Ok. So with Coke's
30:49 , as we'll learn, um this still the model used by CDC,
30:57 Center for Disease Control. Uh when an outbreak, they go to the
31:02 , they try to do various epidemiological . Um uh talk to people in
31:07 area who've been affected, how many been affected, where were they
31:10 And all this kind of stuff goes it. Uh But one of the
31:13 is to go, OK. What's cause of this outbreak? Ok.
31:18 you have to have some kind of to follow. OK. And this
31:23 still used, although we've obviously learned lot of things since the 18 sixties
31:28 relation to infectious disease. OK. while he was correct in his
31:35 we now have a lot of knowledge where pitfalls can occur where there may
31:41 some changes that we have to do some of these postulates uh that because
31:46 learned a lot more. OK. so talk a little bit about that
31:49 a second. But for now, he kind of had it easy right
31:53 of the gate. OK. Looking this disease anthrax, which at the
31:59 was affecting a lot of cattle uh he lived out in the country,
32:02 was a country doctor and you could the effects of this disease on
32:07 And so he said, OK, me see what this is about.
32:10 he took samples of the blood from affected animals. And he could see
32:14 obviously that these what are called bacillus shaped organisms in chains, right?
32:22 present in, in only in the of affected cattle, not in healthy
32:27 . Very easy correlation. OK. is what's causing the disease. It's
32:31 found in diseased animals, not in animals. OK? And so it
32:35 required having a microscope and a sampling blood. That's it. You didn't
32:40 to culture or anything or nothing, ? So it was kind of easy
32:43 out of the gate to go. . Now, I can establish my
32:47 um principles here and uh but then got a little bit harder uh when
32:53 went to look at tuberculosis. So, so now we go from
32:57 theory of fermentation to germ theory of where microbes are the cause of uh
33:03 infectious disease state in the body causing symptoms of the disease are in the
33:10 , right? Um And so, of course, it's also involved animal
33:16 like rabbits, mice to test this, this this theory in
33:21 So etiology refers to cause of OK. That organism microbe x causes
33:28 . Why? OK. And um so tuberculosis. So it required this
33:35 now where we get the stuff you're in lab next week, you
33:40 same, same techniques have been around 100 100 plus years. OK.
33:46 um again, if you want to tuberculosis organism, that's all you want
33:52 have in there. If you don't other stuff to complicate your results,
33:55 ? So AIF technique was developed how do a Petri dish and, and
33:59 plates and that kind of stuff was during this time. OK. And
34:05 , uh so it required the tuberculosis . Uh uh uh uh one is
34:12 with tuberculosis, it's not really in blood, right? So you couldn't
34:15 at blood samples and make it as as it was with anthrax,
34:19 So it's a respiratory illness, it's the lungs, right? And it's
34:22 relatively small microbe, right? So your body has microbes in them,
34:28 you have your microbiome. So it be kind of hard to just visually
34:32 what's what and what's causing the OK. So that involved,
34:37 Now, we gotta get a way culture these things. OK. And
34:42 he would take samples um from affected , you know, when you have
34:46 respiratory illness or coughing and you know uh what do you call sputum comes
34:51 , right? So that's what you use as your sample and he would
34:55 grow them on a plate. And so this involved big plate technique
35:01 you'll learn next week. And um allows you to get a vis a
35:09 and physical representation of those cells on plate, right? Because liquids not
35:16 , right? Because they could grow in liquid. I've already seen
35:20 But in a liquid, you can't you can't, you don't have a
35:25 of tweezers to pull out the cells then look at them and manipulate.
35:28 not possible. So you need to them on a plate, grow from
35:31 plate, they grow in the right? Then you can take individual
35:36 , OK? And you can right? So that plate initial
35:42 they have 2345 different types on Colony types, different color, maybe
35:47 forms. Uh There's if you were this week, you learned about growth
35:52 a plate and the different um right? Elevated colony um margin,
36:00 ? These kind of terms that's how can distinguish different types, right?
36:04 then you can go OK, I'm pick this one and transfer it to
36:08 new plate. I'm gonna pick that and transfer it and then you can
36:11 pure cultures where it's only that one on the plate and that's what you
36:15 can work with um all stuff. be doing a lab. OK?
36:20 liquid media has its use and its . Oops not yet has its use
36:26 if you wanna get volumes of right? Because you can grow a
36:30 50 mils, 500 mils, 100,000 , right? So if you need
36:36 have, you wanna isolate DNA, wanna isolate protein or whatever the purpose
36:42 , you can grow it in large . You generally need lots of stuff
36:47 work with. OK? And that's liquid comes in. If you wanna
36:49 a growth, growth, steady growth it, liquids typically your, your
36:54 to OK. So each form has of its use. OK? Because
36:59 cannot get a pure culture unless a is somewhere involved in that.
37:07 That's how you can get it on , on a plate, you can
37:10 and transfer to a fresh plate and pure cultures and you can only do
37:13 with plates. OK. Um All . So let's look at this question
37:19 . Uh So this is about Coke's which among AD E is, is
37:28 . OK. So remember you have four postulates? All right, but
37:33 learned a lot in the past 150 since this time. So we're gonna
37:40 not everything we know now is consistent each of these, but one of
37:43 uh and um ignore F OK. meant to take that one out.
37:50 one of these is consistent. So OK. So one is as
38:02 wrote it. OK. The other wasn't really aware of. OK,
38:10 me uh pause this here for a . I also found a badge,
38:24 , a security officer, I put on Sheriff of Microbiology. OK.
38:39 uh count down. OK. yeah, if you did answer uh
38:55 OK, you are correct. So which is um one of the
39:01 in the process that he established. . Um The um he was able
39:07 culture the organism on the plate and it into a healthy animal, healthy
39:13 came down with disease. But ABC D are things he really wasn't aware
39:18 . OK. Um Let's go through the actual postulates are and then we'll
39:24 back to this. OK. So the, so for him, uh
39:31 having uh culturing it on a so there are actually two culturing steps
39:37 in science is a good thing if can reproduce, reproduce data.
39:42 So that's really one of the strong about this process, uh his
39:46 And so step one was OK. microbe is found only in uh diseased
39:53 , not in healthy animals. Step one, step two is in
39:59 diseased animals. You can isolate the microbe and grow it in pure
40:06 right? That you, you could that every time. OK? Then
40:11 OK. I can take this microbe pure culture and inject it into a
40:16 animal, healthy animal comes down with same disease symptoms, same everything.
40:21 . Then which is what the good is two culturing steps and each time
40:27 get the same exact thing, That's pretty good evidence, right?
40:31 so the the um uh the healthy , you injected succumbs to the same
40:37 and you can then re isolate same microbe out of that animal.
40:42 . So we know there are certain that we've just learned. Right.
40:48 one of those certainly, uh, certainly knew, we knew this way
40:52 COVID. But, you know, of the things with COVID was asymptomatic
40:56 . I heard that all the time the news. Right. So people
41:00 definitely carry pathogens and not be sick them. In fact, a number
41:05 human diseases are due to healthy individuals those pathogens. They're the source for
41:12 outbreak. For example, like you got, you got vaccinated for
41:16 coming here when you have outbreaks of , say like in the norm or
41:20 is traced to a healthy individual who has it naturally in their throat and
41:26 cough or something that goes out and individuals could come down. Ok.
41:32 So a lot of, you men meningitis, measles, mumps,
41:37 of different human diseases are due to carriers. Ok. Um He
41:42 he was not aware of that. wasn't OK. One disease, one
41:46 . So we had this kind he thought there was a relationship between
41:50 infectious disease could only be due to particular pattern. That's it.
41:56 Not true. Ok. Um uh examples, we have an example of
42:04 , let me think of an example that one where a disease would be
42:12 the one disease would be caused by than one patient. Anything.
42:18 Yes. No. Guess that's too . Thanks. Think of a respiratory
42:30 . Pneumonia. There's one caused by of different things. Bacterial fungal
42:36 is pro protozoal causes of pneumonia, ? Um, the um, one
42:45 , one disease. Ok. The one is one disease. One
42:49 Not always. Right. Second one one pathogen. One disease. Not
42:52 right. You may think of one or one pathogen can cause multiple diseases
42:59 you had strep throat. Ok. organism can also cause flesh eating
43:06 It can cause scarlet fever. It cause um other kind of skin
43:14 Ok. So there are exceptions to too. It's not, it's not
43:18 things always one for one. The uh passengers may not be able
43:23 be cultured. Definitely true. So this, this does not
43:28 Ok. Ok. Syphilis. Uh the bacteria that causes syphilis has been
43:35 since the 19 1900 still can't culture in the lab. Ok. Uh
43:42 , it's very easily detected through um lot of these things are detected through
43:47 imm processes. Antibody engine detection. . Uh So just because we
43:53 culture doesn't mean we can't cure it ? Diagnosis and cure it. We
43:57 can't. Ok. Um The the other wild card here is
44:04 If, if Coke started with a that was viral, forget about
44:09 He wouldn't be able to figure anything , OK. You know anything about
44:13 back then, right? No way even culture them. They're so
44:17 OK. So he kind of, know, you're lucky in a lot
44:20 ways too. And what he was . So elect a suitable animal host
44:24 applies to certain bacterial types. Also , you may not, you may
44:29 , they may not, they may grow in that host. So sometimes
44:33 an issue as well. So, again, as I said,
44:38 the postulates that he established are still viable framework. We just know where
44:46 may not be totally consistent, And so we're aware of that.
44:50 . And it may be that it's cultural and we're OK, we
44:55 we can work with that, we figure it out still. OK.
44:57 just we just have more knowledge and can, you know where maybe the
45:01 may occur. OK. Any questions that? OK. All right.
45:08 , um all right. So if you're working on, OK,
45:12 establishing that certain microbes can cause certain diseases. And obviously, the next
45:17 is how do we get rid of ? How can we help people that
45:22 sick with these infectious organisms? And so now we go into fighting
45:27 , um drugs, uh et OK. And so uh vaccination was
45:34 by accident, I'm assuming uh actually like back in the 16,
45:39 maybe late 15 hundreds, early 16 . Uh smallpox outbreaks were all over
45:46 place of the world, especially in . And I don't know what,
45:51 made the person think this. But had the idea to, because we
45:56 smallpox, you have all these little all over your body, called them
46:00 , right? And those bumps rash are full of active virus.
46:06 So somebody had the idea of cutting of those pustules then inoculating a healthy
46:12 with it. Why? What made think to do that? I don't
46:15 , maybe some random accident, who ? But that in many cases that
46:20 who was vaccinated, right was They never came down with disease.
46:26 then they go OK. I this is a thing we can
46:29 right? The problem is those pustules 100% live active virus, right?
46:35 not everybody that they got quote lived, right? They can pop
46:40 and die, right? So we to come up with the other ways
46:43 kind of vaccinate uh but make it . Ok? And that's where attenuation
46:50 in. Attenuation means to to limit to um to um inactivate, make
46:59 , make it still that it can , body can respond to it,
47:04 it can't um kill the person, ? That it can't be active and
47:09 disease in the person, right? ultimately the goal you want.
47:13 That's what attenuation is all about. Now before then, uh Jenner kind
47:19 did it in a different way rather attenuation. Ok. Using a different
47:27 , similar to smallpox but not identical smallpox virus. The cowpox,
47:33 And cowpox is a benign disease in . Ok. And, um,
47:38 had the idea to go. let me try this. It turns
47:42 to work as well. Ok. vaccinated with cowpox virus didn't come down
47:46 smallpox or had much, much, lesser symptoms of disease. Ok.
47:51 wasn't fatal. Ok. Pasture of , has hand in everything and
47:57 in, in the vaccinate vaccines as . He, he came up with
48:01 rabies vaccines, one of them among . Ok. So, attenuation,
48:05 . So we're trying to limit uh activate through various mechanisms and heat temperature
48:12 , many different ways to do And so of course, the this
48:17 the mechanism at play here, I'm , you know, is the body's
48:23 response, right? And so we a pathogen is put into the body
48:29 the person acquires a pathogen and on bacterium or virus or, or zoen
48:37 fungus or whatever the pathogen is, be, it'll illicit a response,
48:43 ? So, antibodies responding to right? So, antigens are the
48:49 that are on uh the surface on periphery of the bacterium or the virus
48:54 whatever it is. Uh that because what the body can see,
48:58 Um Your immune system cells can only what's on the outside of the
49:03 And what's out there all different types protein molecules, uh a flagellum made
49:08 protein, uh a viral spike You heard those in the COVID
49:13 the virus COVID virus, right? those are things on the outside and
49:16 what your cell can respond to. one of the responses is to produce
49:22 . OK. We're doing all this at the end of the semester.
49:27 . But antibody and that's what you , it's obviously the basis of
49:31 OK. So you want to uh the bacteria virus, inactivate it in
49:38 way and but still retain the ability induce the immune response. OK.
49:46 that's, that's what you wanna Now, of course, there's all
49:49 of ways to do that. You deal with whole bacteria, whole
49:56 But nowadays, often it's genetic right? COVID virus, the COVID
50:01 is RN A, right? So RN A is expressed expresses the engine
50:07 then your body responds to the So it's much safer. You're not
50:11 a whole organism into somebody as a . You're just taking the parts that
50:16 the energy. OK. And so different ways to do that as
50:20 OK. Um So the question why was cowpox magazine effective? Even
50:27 it did not contain smallpox, I mentioned, right? Very similar,
50:31 have something very similar. OK? can have very similar antigens and produce
50:36 same response. This is a phenomenon um cross reaction. OK. Cross
50:47 antibodies. OK. Now, that actually have, that can be a
50:50 edged sword because we'll learn that there's uh pathogens that get in your
50:58 They may have antigens similar to your molecules. And then you produce antibodies
51:04 the pathogen, but then you produce to your own tissues, right?
51:08 condition that can occur. There's some diseases that produce that effect. Rheumatic
51:14 is one of those. So sometimes doesn't always work in your favor.
51:19 ? Um But again, it's all antibody engine binding recognition and binding.
51:25 . I said we'll learn about this the semester. So here I put
51:29 one in, this is one of uh pet peeves is the, is
51:34 misuse of the word sterilization, So I put this one in
51:39 Which sentence below is correct. Oh That I even open that
52:08 I said, OK, so somebody at me when I do that.
52:11 tend to do that sometimes. So yell at me. OK.
52:38 Let's speed this up a little bit 1312. OK. Um OK.
52:58 Who answered? Um oops who answered who answered C oh, there's only
53:12 of you. I know who answered anybody want to pass up? Let's
53:21 . I know how to find I'm sneaky here. Uh See.
53:27 it this one? Yeah. Who C Tess Chan where Tess chan.
53:38 . Come on. Is that Ok. Are you sure?
53:44 who's Tess Tess? You're right. are you? Ok. So,
53:51 , what is, thank you uh, raising hand. So,
53:55 it a completely random guess, or knew it disinfection? Is, is
54:10 what, how do you use that ? If you're going to disinfect
54:14 it only applies to what? And then a bench top,
54:19 doorknob ahead. Right. So, um you're, you're like I
54:23 you're right. So it's, it's you, if uh you sterilize,
54:27 my arm was sterilized during this, arm would probably be not there
54:31 OK? Um If it was I was put in an autoclave,
54:35 ? So I'm gonna come out OK. Uh If I have a
54:39 sterilizing agent, it's gonna be so that it's like flesh of me falling
54:43 , right? Uh It'd be but it wouldn't be functional,
54:46 So, um this infection is uh mentioned, right? Inanimate objects,
54:52 ? So for sterilization, disinfectants, gonna be much harsher whether it's chemical
55:00 , what have you uh processed to, to, to do the
55:05 vector of sterilization. So, sterilization if you sterilize something, if I
55:10 this two square inch area on this , OK. I've sterilized it and
55:17 means there's no detectable cell spore or on that area, it's all gone
55:25 . OK. Um This infection um obviously disinfection reduces levels, but you
55:33 go down to zero. Ok. , you know when you have a
55:38 , just look on the bottle of or what have you, you'll see
55:41 the label, uh certain test organisms they're tested against, right? Specific
55:48 , viral bacterial. And they say against ABC DEF strains, right?
55:54 proven to be 99.99% effective, 99.99% . You, you're not going to
56:02 . You still have let things OK? Uh So the correct term
56:10 that is antisepsis. OK. antisepsis is using chemicals or other that
56:20 living tissue, your skin can OK. Beta dyne kind of brownish
56:27 . You might see in the black office um uh the Isopropyl alcohol,
56:33 what the swab is, right? these are kind of, these are
56:35 we call anesthetics you can put on skin and that's, that's what it
56:39 . OK. So uh remember that you go to lab. So in
56:45 and you, you taking the ethanol you put it on the countertop,
56:50 disinfecting it, you're not sterilizing OK? Um OK. Showing growth
56:56 unwanted microbes. So, disinfectants and we just talked about those. Um
57:04 and just the two names are you know, semi Weis and
57:07 Lister uh used uh I forget what chemical was, but it was um
57:14 surgical instruments is what he did um . So both of them similar
57:18 hand washing to reduce um infection. and it, it really had a
57:23 effect, do doing those things in of minimizing post-operative infections and, and
57:30 like that. Ok. Antibiotics, course, we don't know about
57:34 So remember that antibiotics are, are produced. Of course, nowadays,
57:38 , we s we can synthesize these , we can do chemical modifications on
57:43 to kind of tweak their activity and , but we still go out and
57:47 how to find new ones as OK. Uh Obviously penicillin. Uh
57:52 so any kind of inhibitory action by will be seen by kind of this
57:58 . So penicillin, mold sitting there you can see a streak plate of
58:02 that there's an area around that mold , there's no growth occurring because the
58:10 chemical it's releasing is diffusing out and the growth, right? So,
58:14 know, oh, that must be kind of effect. And of
58:17 they've discovered penicillin that way. But , we know nowadays of antibiotic
58:23 which is a major problem. And not only just bacteria resistant to
58:29 single type of antibiotic, but multi types, very difficult to deal
58:34 OK. Don't worry about having to different mechanisms of, of resistance,
58:39 ? Just put this up there just visual purposes. Uh We'll talk about
58:43 later in the semester. But um know, they target for antibiotics and
58:48 reason why you can get resistance because have, they have single targets in
58:54 cell, whether it's affecting a component protein synthesis or an enzyme involved in
58:59 cell wall synthesis or an enzyme involved uh replication. So they have single
59:06 , right. So it's not that considering how bacteria, for example can
59:12 so fast. They can acquire mutations to get just one mutation to counteract
59:16 effect of antibiotic is not that Really? Ok. Uh What you
59:22 though is to have exposure to the . That's where the, that's where
59:26 issue comes in is misuse of creates that environment to produce resistance.
59:33 Antibiotics are everywhere, right? Just a sample of wastewater and you have
59:38 . We have a bunch of those in there, right? The food
59:41 eat, right? We inject chickens cows with antibiotics, right? To
59:45 for food production because when you're growing animals in well in closed quarters,
59:52 say, ok, a bazillion chickens a coop, right? Uh disease
59:57 pretty quick, right? If if one of those is infected,
60:01 you gotta give them antibiotics to minimize , right? And so of course
60:04 you, you ingest that and then contribute the problem as well.
60:08 So resistance kind of come about in various ways, right?
60:12 they can uh pump the antibiotics they can change the target slightly.
60:17 the antibiotic can't bind to it. can um uh modify, modify the
60:23 and pop them out, uh produce that maybe destroy the antibiotic altogether,
60:28 ? So it's a war back and between us and them and trying to
60:33 on top. OK. So the last part here, I'm gonna dimension
60:40 will correlate uh I, I put last because it will correlate us going
60:46 the next couple of weeks, which all about metabolism. OK. So
60:52 a any questions about antibiotic resistance or ? OK. OK. So uh
60:59 ecology. So this, so until time as I mentioned, right?
61:06 , you could, you could grow on a plate, you could roll
61:09 liquid, uh you can isolate But what most we're dealing with if
61:16 all we're dealing with were types that grow on something like a beef
61:22 Think of Campbell's chicken noodle soup, chicken beef broth, whatever like that's
61:29 complex, organic material and lots of can grow on it. OK?
61:34 that's what most microbiologists were dealing If not all of them, we're
61:37 types that would grow on that. ? A very rich medium we call
61:42 . OK. These guys when the at al um discovered these types that
61:49 completely different in terms of metabolism. . So uh they could use food
61:55 for energy that were inorganic. H two S ammonia, um
62:04 right? Things as you go. goodness. How can you get energy
62:06 that OK. This is what we the litho troops. OK. So
62:12 means a rock eater. OK. are inorganic materials for the most
62:18 I think. Um and so synonymous that term is this one chemo
62:25 So they're both synonymous liso troph, autotroph. OK. And so the
62:31 chemo autotroph, you know chemo and . So the chemo part tells you
62:37 gets this energy from chemical reactions, oxidation, OK. As opposed to
62:44 , you have chemo, we're gonna photo, right? Photo is using
62:47 , right? So chemo is using non light chemical reactions to get
62:51 The autotroph part because you can have autotroph, photo heterotrophic, chemo
62:57 right? So the hetro part points what is the what is the sea
63:06 , right? Um Is it co2 it something more complex like C six
63:15 1206 glucose, something like that, ? So two fundamentally different things
63:22 OK. And that's your autotroph hetero . OK. Uh That will definitely
63:31 be the last time you hear that the next three weeks. So you're
63:34 get sick of it by the Um Anyhoo. So uh again,
63:39 inorganic sources, that's what lithos how they do this. Well,
63:43 can imagine it might be kind of to grow on a plate because they
63:46 didn't know what they actually did first to take a soil sample.
63:52 And they uh applied like I think ammonia, right? So you have
63:58 soil, take a, take take a pan of soil and you
64:03 it in an enclosed chamber and you hydrogen gas, let's say,
64:09 then you monitor it every day and notice, hm, hydrogen gas is
64:14 away. What's that all about? ? And so you then take that
64:21 , same soil and you autoclave you sterilize it. OK? You
64:27 any living thing in there. Repeat experiment. Put H two in
64:30 H two is not disappearing, it's there, you know. Hm.
64:34 must be something in the dirt that's hydrogen gas to do some kind of
64:41 products. What in the heck is all about? Right? And micros
64:44 use H two. That sounds right? So that's what led them
64:48 this path. And so they use column. OK? Which is really
64:53 um I actually did one of these times by the there's a pond over
64:58 by the Technology Center. I think took some mud from the, from
65:03 edge and put it in this And the same thing happened. I
65:06 these different layers with it took like months before you actually saw something,
65:10 in any case, so you got mud of course, is a source
65:14 microbes, right? Bacteria. And course, it's gonna be all different
65:17 in there. It's not a pure obviously. But then you add things
65:21 pretty basic, right? Shredded So news newspaper is the source of
65:28 , remember what you, it's a of, well guess it's carbon
65:36 right? So clos papers made of but C is a carbon.
65:41 It's a type of sugar. And you have that, then you add
65:45 like calcium salts of sulfate. I think they added like eggs,
65:49 are rich in sulfur, like eggs egg shells would have eggs, shells
65:53 have carbonate and calcium salts in And you know it put it all
65:58 that sit on the shelf. Light IOT. And so um so
66:03 uh is a source. We have carbon sources. We have this,
66:08 the newsprint newspaper. OK. Sly . And then you have the car
66:15 which can be converted to uh CO2 the micro pass the right enzyme mean
66:22 that CO2 and then that's that, your autotroph source, right?
66:26 And so you could grow then these metabolic types, right? Autotrophs,
66:31 and the same thing. And so see is a layering tiers of
66:37 right? Top bottom, right? again, so that would be a
66:42 of oxygen as well. More oxygen front on top, none as you
66:47 to the bottom, right? So gradient of 02. OK. And
66:51 what you get different types? So that can utilize the um um sulfate
66:59 provided, right? And reduce that H two S that can be used
67:05 others as a source of energy oxidizing to uh elemental sulfur. Um You
67:12 the H two being utilized as a . And so these are all anaerobic
67:20 down there processes. You have santa and these are types that are photos
67:27 just like a plant, right? water to oxygen, utilize sunlight.
67:33 Big CO2. OK. And you have uh other types of photosynthetic bacteria
67:39 can use other things in water like , for example. OK. And
67:44 so this opens up this whole new of microbial activity that didn't even think
67:49 it existed, right? It really to the diversity of metabolisms you see
67:56 among the prokaryotes. OK? And we'll learn that this process here or
68:03 a nutshell. OK? You I just, there's a question coming
68:08 , you have um a source, ? And you have a source that
68:19 oxidized, it's called a food right? That becomes oxidized.
68:25 And then, and as it becomes , it releases electrons, right?
68:30 then goes through an electron transport Don't worry about writing this down.
68:34 And then those electrons are tra traveled here to a terminal acceptor.
68:44 And so for you, that's OK? And that becomes water.
68:51 . So uh it's all about electrons passing through and those when you transfer
68:57 and releasing energy and the energy is then to pump protons out.
69:05 And then you harness that right? having this thing called uh A T
69:13 TP ace. OK? Because as protons go down, they release energy
69:20 they use that to make a OK. So in a nutshell,
69:25 basically describe to you chapter 13 and , right? So we're done,
69:28 know, but that's, you that's, that's what we're gonna be
69:31 on in the next couple, three , not just that, but you
69:34 , kind of fleshing it all OK? But there in the microbial
69:40 , you can have things other than at the end that it can respire
69:44 I mentioned nitrate respiration, right? can have different food sources, it
69:48 be glucose, it can be something . So all the front and back
69:52 can be mixed and matched in different . OK? And that's what gives
69:57 what they use, what they use and what they use here at the
70:04 tells you what kind of metabolic microbe is, right? Is the photo
70:09 is the chemo water trope is this is the that right. So
70:14 , and this collectively is respiration. ? That process, OK? Can
70:21 aerobic or anaerobic. OK? It be using an inorganic source, using
70:27 organic source. OK. So that's which is completely different from what we
70:34 in the past year. So what the yet fermentation is involves nothing
70:45 what I just mentioned not more basic or simple, right? So
70:53 like I said, I describe to what we'll be talking about in the
70:56 two weeks. So if you didn't this down, don't worry about
70:59 OK? We'll, you, we're go through it and nausea.
71:04 So let's um let me do let me erase um this.
71:12 So here's uh li like trophies in for energy. Here's kind of a
71:17 . OK. Um ammonia, ammonium , potassium phosphate, magnesium chloride,
71:24 chloride, iron, sulfate, ferric . However, uh we provide adequate
71:30 create at the right temp maybe add couple of vitamins, right? Um
71:34 . So we got that recipe. the question is what else does it
71:40 ? OK. Um Many ideas, we're supplying it at this point.
71:47 there something else we need to What kind of your kind of,
71:52 based life are you? Are you based life? Carbon based life,
72:02 ? You are carbon based life. don't see, do you see a
72:13 with? See, right. We calcium, we have chloride but do
72:19 see something with ac in it? . So we need to have something
72:24 um for a litho trope, it's be CO2. OK. We need
72:30 have co two. The missing ingredient this case would basically come from the
72:34 . OK. Co two in the or we supply a carbonate molecule and
72:39 will convert to CO two. But that's what an nope is.
72:43 is. No. And so whatever life form you are, you've
72:48 have this, right? Because that's you make your molecules of,
72:52 DNA RN A proteins, carbs these are all based on AC C
73:00 framework, carbon framework and you add to it, right? So
73:04 you can't make those unless you're, eating carbon and um that's what we
73:10 , we get ours from eating where gonna eat for lunch today. That's
73:13 be a carbon source for you. ? Um You can't use CO2,
73:19 ? Um You can try it, ? But you're gonna die.
73:25 So you need to have organic OK? And it's a kind of
73:28 dumb thing to say, well, is not organic, is, is
73:32 . No, it's not, it organic but it's the most, it's
73:35 most simplest organic carbon form, You can't take CO2, right?
73:41 looks like this. You can't break down, right? Life can't break
73:46 down and get energy from it, ? You can only build with
73:50 right? So you build complex molecules this, right? C six H
73:58 . And when you're building stuff, takes lots of energy, right?
74:01 you're making something small into something big so you need energy to do
74:06 And where does the litho trope get from? From oxidizing things like
74:12 Where does the plant get it from . OK. That's the way the
74:17 works, right? You're an autotroph a head atrop. OK. So
74:21 the um so with this discovery of litho troops and these various metabolisms,
74:28 can then see how their metabolisms are in the cycling of the various
74:35 right? So in an ecosystem, you gotta have these supplied,
74:40 And in many cases, it's right? So we actually have a
74:44 , a basic uh yeah, basic cycle, right? So you have
74:50 , right? You have consumers up . This is a nitrogen cycle.
74:55 talk about that later, but the atrophy here is right on the
75:02 on the bottom one, right? . This is the part that's the
75:06 trophy, right? They're taking these , breaking them down and getting energy
75:12 it. That's what lit litho troph do. OK. Um So the
75:17 autotroph thing. So I know, me go doctor. That is so
75:21 . I learned this stuff in junior . OK. Trust me, I
75:26 Kier is doing this that you you know it, then I'll get
75:29 and what's not, right? So it. OK. Um And
75:36 you know, obviously cycling, autotrophs, hetero trope, we eat
75:41 up CO2, right? And that's goes in the atmosphere and that's what
75:44 can use. OK. So certainly , right? Fungi, uh bacteria
75:49 the soil breaking down that organic material elements and components that others can
75:56 right? So uh where are microbes in this cycle on one spot or
76:08 ? Everywhere they're in all levels, ? Your bacteria that sort of synthesize
76:13 bacteria that consume your bacteria that decompose everywhere, right? Ubiquitous.
76:20 Um So autotrophs are producers. Header are consumers. OK. So you're
76:31 hetro, you're a consumer. So um I'll come back to that.
76:39 do that the first thing that, first thing next time. Let's look
76:43 the after this is the same question had earlier. So let's uh let's
76:47 that real quick. OK. Same . So let's see if you change
76:56 mind here. Um So these things were talking about the hetero trope autotroph
77:02 troops, right? Uh We'll begin get in, get into that stuff
77:06 week. OK? But remember, be scared or intimidated by what you
77:11 in chapter 13, right? With the reactions and this and that I'm
77:16 condense that for you. OK? you an expert at it.
77:24 Mhm. Yeah. OK. Calm . Not. Mm That jumped up
77:50 a hurry. OK. Uh Let's . Went from the correct answer.
78:01 OK. A is wrong. B wrong. C is wrong. B
78:09 wrong. E is wrong. F F is the correct answer. So
78:16 went to 53 on that one. . All right. I'll, I
78:20 post Monday's question. Clicker questions. do that. I forgot So you'll
78:23 all these extras will be available to . So don't forget the uh,
78:28 on Friday start opens Friday. See you all next
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