YouTube Lecture 1

Did you guys hear that? Okay. Yeah, I did. All right. Lecture number one, continuation. We're going to start with the question of the day, which is, what is the three-domain system of life? And this has to do with the material that we went over last week. I mean, sorry, on Tuesday. So go ahead. And who wants to answer that question? I'll let you know. It's bacteria, archaea, and I think it was eukarya, right? That is correct, Richard. Bacteria, eukarya, and archaea. Now, who developed this? His name was like Wills? That's right. Carl Wills. And this is based on what? The 16S RNA nucleotide sequence. That's right. It has to do with the 16S rRNA nucleotide sequence because they are all different between those three domains. Okay. So anything, what that means, like someone said, well, how do I know what that is? What that means is that anything that's living is going to be in one of those three classifications or domains. Within those domains, then we break it down further and further into kingdom, phylum, et cetera. Okay. All right, so let's continue with our lecture. You see my screen, correct? All right, so what we're going to discuss next is classifying and naming microorganisms, because there is a special way in which we classify and we name our microorganisms, and you need to understand that, okay? So what we call it is referred to as a formal taxonomic system. That is what we use for naming microorganisms. See, Carolus Linnaeus, he was concerned with how do we name organisms? When we discover something new, what do we call it, right? So he's the one that discovered or developed this. He wanted to have classification. Make sure you guys mute yourselves. Javon, mute yourself. Thank you. He wanted to make sure that there was order, that organisms were arranged, whether they were by morphology or... biochemical characteristics, whatever it may be that there was some sort of order. We refer to this naming. Professor, can I ask you a question? Uh-huh. I'm sorry to interrupt you. I wasn't here in the last class. Where exactly do we get these PowerPoint slides from? Canvas. But we're in Canvas. Like when I go into modules, which lecture is it? Okay. Do you see under quick links? Go below modules. Do you see the quick links? Do you see lecture one exam materials? Quick links, lecture one exam materials. Lectures and homework? Yes. Click on there. It says lecture one, history of microbiology. Is that correct? That is correct. That's lecture one. Okay, got it. So make sure that you print the lecture lab schedule so that you know which lecture we will be on. Okay? Okay, got it. All right. Sorry about that. No, no problem. Okay, so this is referred to as nomenclature. So I'm going to show you today how do you properly write the names of microorganisms. Because this is a prokaryotic class, right? So we're going to focus on prokaryotes. So let's discuss that. There we go. All right. So naming a microorganism. The example that I have here is Staphylococcus aureus. Now, again, normally I like to give, I do a lot of chalk talk, but I can't do it in this format. So that's why I think you will enjoy the videos a little bit more, but I did the best. So whenever you see something written in red, like you will soon, I want you to write that down. Okay. So that's like my board. So the example here is Staphylococcus aureus. The genus is Staphylococcus. The genus is always capitalized, okay? And sometimes the name of the organism tells us something about the organism. For example, caucus refers to the morphology of the organism. Caucus or cocci means round, okay? So whenever you hear... the word caucus, you know that this is a round organism, that the morphology, which means shape of the organism, is round. There's also streptococcus, for example, right? All right. So staphylo means grape-like. So it's like a little grape-like cluster. And caucus is a shape. So it's a grape-like cluster. Staphylococcus is the genus and it's always capitalized. The species is aureus. And aureus refers to gold, and it's because it has a sort of goldish look to the pigmentation of the microorganisms. Okay. Notice that the species is not capitalized. It's lowercase. You need to be very careful because this could be a mistake. When you write the names of microorganisms in your lab manual, I expect proper nomenclature for all the microorganisms that you will write. And we work with a lot of microorganisms. So how do we actually properly write it? Now that we know that genus is always capitalized. and species is not, how do we write the names of microorganisms if we're writing by hand, like you will in your lab notebook, as opposed to when you're typing your final unknown report? Here we go. Handwritten will be in cursive? That's right. So handwritten, there are two ways that, no, not handwritten in cursive. There are two ways that you can write it handwritten. Because you don't... you cannot write in italics, a computer writes in italics, you will underline it. You can write the whole genus Staphylococcus, capitalized, aureus, not capitalized, and you underline it. Or you can abbreviate the genus and write S, capital letter S, dot aureus. So go ahead and write this down. And you underline it. Notice that in my presentation, I have it in italics because I can use the italics function in my computer. So if it's typed, I can type it in in italics the way that you see it in the presentation, right? Capitalized genus, lowercase species, or I can abbreviate. the genus. At the beginning, I don't usually in the lab, I usually don't abbreviate because students are not familiar with the microorganisms yet. There's a lot of organisms that start, that their genus has an S, begins with the letter S, okay? Like streptococcus or serratia or saccharomyces. So if I put S, you might not know. If I write S. marcescens, you may be like, is that Staphylococcus marcescens? If I write S. epidermidis, is that Serratia epidermidis? You may not know. So at the beginning, I write the whole name of the organism so that you know the genus and the species. Okay? So this is the way that I expect you to write the names of the microorganisms. Yeah. Question. I know on Tuesday, you mentioned that you weren't sure if Ms. Morales was collecting lab notebooks. I know for your class, for your lab, you're stating that you are. That doesn't specifically apply to Morales, right? Because she says she wasn't. I think what she's going to have you guys do is maybe take a picture of a few of your labs and submit it. I'm not sure what she's going to do. But whatever you guys do in your lab, she does things a little bit different as far as the delivery of the materials, but the content will be the same. So whatever your lab instructor tells you, that's what you're going to do because she's grading your lab, not me. There are lab points associated with the lab notebook. So however she's going to assign those, it's going to be up to her. Okay? All right. Let's move on. So as I mentioned, the names of microorganisms can be named for a variety of reasons. The example that I gave you was named, it was labeled that way because it helps describe the shape and morphology. of the microorganism, the morphology rather, and arrangement, which you'll learn the difference between what is the morphology and what is the arrangement. But here we see a number of other microorganisms that were named not necessarily because of their morphology, which is their shape, or arrangement, which is how they congregate. For example, here we see streptococcus, let's see, let's see, let's see, oh, Klebsiella pneumoniae. What do you suppose Klebsiella pneumoniae causes? Pneumonia? Pneumonia. That's right. So that's why it was named Klebsiella pneumoniae, because of the disease that it causes. So sometimes the microorganism may be named because of the, you know, to describe the disease that it causes. Sometimes, let's see, like this one, Japanosoma cruzii was named in honor of Oswald Cruz. Now they made it a little fancy and added the end at the end. but they named it in honor of the person who discovered this. So sometimes then the way that they name organisms is to give you an idea or an explanation of the disease that it causes, maybe the morphology or arrangement of the organism, to honor the scientists who discovered it, or also maybe what it causes or what it forms, like Streptococcus pyogenes. Well, pyo means pus. If you get infected with this organism, you're going to have pus production. So, you know, there's a variety of reasons, not one fits all. All right, so let's change gears now. And we're going to talk about the history of microbiology. I love history. If I wasn't teaching microbiology, I would be a history professor because I love history. And I like to tell stories. And I feel like sometimes students may not remember the content, but if they remember the story, hopefully they will remember. the content behind it. Okay. So here we have some of the main historical figures in microbiology, beginning with Anthony van Leeuwenhoek and his discovery of microscopy. I love history again. And I think his developments were very, very important for his time. Louis Pasteur and his pasteurization, right? He gets credited for pasteurization. And Robert Koch, who developed the germ theory. Okay, so we're going to begin. These are the main historical figures. There'll be others that I talk about, but these are the main ones. But let's talk first about Antony van Leeuwenhoek. So he was actually a Dutch, where was he, tailor. He was a Dutch tailor. And what he did is he developed these lenses, and he would use these lenses to look at the quality of the cloth. Now, he thought it was very fascinating because he was able to see things that he couldn't normally see with the naked eye or he could see it better. And so he started developing these more powerful lenses, if you will, and started getting curious about the things around him. He looked at the stinger of a bee. He would look at pond water. He looked at the scrapings of his teeth. He looked at various bodily fluids. He was very curious. But what makes this guy so interesting is the fact that he also kept meticulous notes in his notebook. If you take a look at this figure here, look at how descriptive he is in his drawings. That's how descriptive I want you to be in the lab. You see figure A, it looks like a rod. You see figure B, look how he outlines the movement of figure B. Who knows what the heck that was, right? Figure G here, you see that it looks like a spirula. We have two rods there. You see he even saw cocci. Cocci are usually a lot smaller than the rods or bacilli. And in figure F, he was very good at differentiating between the different sizes of these bacilli that he saw. And he even has here what we call a vibrio. This is all terminology that you will become more familiar with. as we continue with the semester. So this was fascinating. Nobody had ever seen this invisible world. He was fascinated by this and he called these little live microbes animal kills. But this was his actual microscope, the first microscope that was developed. It was very simple, but it had everything that you need to be able to see. what he was going to see. You see it had the lens, it had the specimen holder, a little focus screw, and a handle. So just like this picture here, he would put it up to his eye against the light to be able to see the microorganisms. Now I have an old microscope. This was one of the more modern microscopes after the development of his. It's very, very simple. I would put the sample here. Now it has a little actual sample holder. It has the focusing knob, but I do need a light source and I have to put my eye there. You know, it's more like a museum piece for me. I had a former student that had inherited that from his father and or grandfather or great-grandfather and gave it to me. So that was really, really sweet. And I really treasure it. So here you see more of his documentation. Just amazing, amazing. But this really rattled the scientific community. I mean, if you can just imagine, he is posting or documenting information that had never been heard of. What? What do you mean? There is an invisible world that exists that we can't see? Sorry, that's my co-chair calling me. That is crazy. Hold on a second. All right, so this rattled the scientific community because now we have this invisible world come to life. Well, what is the big deal? You see, the big deal is that people back then, and this was in the, what was it, the 1600s, right, mid-1600s. People believed in spontaneous generation. And what that means is that they believe that life arises just, boom, spontaneously. You know, people believe that... Moist soil will breed mice and toads. That decaying bodies would, you know, automatically give life to flies. That's what people believed. And so when this came about, it was like, huh, so you mean life doesn't happen spontaneously? Life cannot just automatically happen like magic? Well, we don't know, right? So there was this other belief then, and those people that believed in biogenesis. Biogenesis are those folks that believe that living cells can arise only from pre-existing living cells, that life does not spontaneously occur, all right? So again, after Lew and Hoke's discovery of this previously invisible world of microorganisms, right, the scientific world became very interested in the actual origins of life. So now we're going to talk about the researchers who... finally put an end or figured out which one is true. What do you believe? In spontaneous generation or biogenesis? Genesis. Biogenesis? I sure hope so, right? But remember that spontaneous generation stemmed from Aristotle and that was like what, 300 BC. So this belief of spontaneous generation was acceptable for more than two... 2000 years. It's not more than 100 years ago that people actually believed that moist soil would breed mice and toads. So it was going to be a very difficult idea to disprove, you can imagine, right? So let's talk about that journey. Spontaneous generation versus biogenesis. So here we have this scientist, Francois Reddy, and he actually did a simple experiment. He had three jars with three pieces of meat. One he kept open, one he kept sealed with the cork, and the other one he put a gauze. All right. So the idea is he waited and sought to see what would happen. What he noticed is that the jar that was open, flies would come in and then maggots would form. He's like, ah, so what happens here is that Maybe life doesn't spontaneously happen, but what happens is that it's these flies that are present and they lay their eggs or whatever on the meat and that's why we have these maggots, right? The other flask, the meat spoiled, but there was no maggots. And the third one, it was covered so air can go in. Now remember, air is going to be an important factor in this. Air can go in the flask and the flies would try to get there, but no maggots formed because the maggots were not allowed to go inside. All right. Oh my God, I remember this. So rotting meat, what he found is that rotting meat does not spontaneously produce maggots. That was crazy. That was wild. The scientific community didn't know what to make of it. So what did they do? They tried to do everything they could to disprove Reddy's experiment. Okay, so this is where we go into John Needham. Needham was an English biologist and priest. He believed in spontaneous generation. So he conducted an experiment to basically disprove Reddy's experiment. He was not happy with those results. Okay. And so what he did is he boiled brief gravy and then he tightly sealed it with corks. Days later, it was cloudy. So he showed the scientific community. You see, I boiled the broth. I even put a cork and it's cloudy. And the only reason that it's going to be cloudy is if there is life. So therefore, spontaneous generation all the way, right? He believed that there is a life force that causes inanimate matter. What is inanimate matter? Not living, right? That causes inanimate matter to spontaneously, boom, come to life. Well, this impressed the Royal Society and they elected him a member in 1747. All right, 50 years later or so, we have Spionzani, Lazzaro Spionzani. Now, he was an Italian priest. Yes, a lot of these scientists and biologists were priests or in ministry and all that, you know, monks, because that's where they had the time and they... had the means and be able to do these kinds of experiments. So that was not uncommon. He was an Italian priest and he contradicted Needham. So what he thought, what he did is like, hmm, you know what? I think there may have been some errors in Needham's experiments. So I am going to make sure that I'm more thorough with my execution. So what he did is he boiled, he did the same thing. He used the beef infusion, a broth. But what he did is he boiled it for one hour. We don't know how long John Yadam boiled his. We don't know. He just said that he boiled beef gravy. So Spagnanzani boiled it for one hour. And then to be sure, he melted the necks of the flasks to seal them, to make sure that nothing would go in. We don't know how tightly he screwed that. cork in his flask, how we know what Needham did. We don't know that. And what we found, or what he found, is that the flask that Spagnanzani had boiled with the broth remained clear. And unless the seal was broken, it remained clear, you see. So he did believe that Needham had errors in his experiment. Maybe, like I said, he failed to heat the vials. correctly or well enough or long enough. His seals may not have been tight enough, but more importantly, Spagnanzani believed that all living things come from pre-existing living things. So do you think that they invited him to be part of the Royal Society? Yes. No. No way. Nope. Critics claim that there is a vital life force in the air and so by him melting the necks of these flasks didn't allow that life force that's in the air to come in and allow spontaneous generation so no he was not invited what do you say about the eight supposedly there's a certain amount of grams that leave a person's body after the person passes away do you believe there's some type of life force i'm not trying to say i'm a true believer in and all this nonsense. But, you know, some of their, I believe the truth is in the middle. That's one thing I've always believed. Yeah. Well, I, I'm, I'm right now we're talking about spontaneous generation life coming from pre non-existing non-living things. You know, when you die, your cells are, some of them are still living and growing or whatever you may call it. I mean, hair still grows, your nails still grow. So there's your vital organs may be deceased, but there are certain cells that may still be functioning, but we'll stay on task. Okay. So spontaneous generation versus biogenesis. Nope. I think his experiment was valid, but they did not agree. So not until 62 years later, 62 years later, what we have is Louis Pasteur. Louis Pasteur brought a final end to the idea of spontaneous generation, but that's not all he did. You see, this guy was amazing. He showed that microbes cause fermentation and spoilage. He developed pasteurization, which we will talk about later in greater detail, the different methods and different types of pasteurization. He developed a rabies vaccine, but arguably one of the most important things is that he disproved spontaneous generation of microorganisms. How did he do this? He used a swan-necked... flask. Very interesting experiment. What he did is he pour his beef broth, because that was the thing to do, right? In this long flask, he boiled it long enough to make sure that he killed everything. But before he did that, notice the design of this flask right there. You see that? How cool is that? And remember that the critics, he didn't seal it. Because remember that one of the criticisms of Spagnanzani's experiment is that by him sealing the flask, he was killing the life force that exists in the air. Correct? Remember that? Yeah. Yeah. And so what this does is the following. This type of design allows air to go in through the tube and down here. And any microorganisms, because remember that I told you that microorganisms are ubiquitous. That means that microorganisms are everywhere. So yes, some microorganisms will come and land here, but what will happen is that they're going to get trapped. right there. See, they'll get trapped right here. And microorganisms that are trapped there, they're not going to, you know, walk up and then down into the broth. They're not going to do that. They can't do that. They can't climb. They're not climbers. They can fall in there. This is what you actually find still. in a museum in Europe showing Louis Pasteur's swan-necked flask. So this remained clear, and only if you tipped that flask and reconstituted this pellet of bacteria, then this would become cloudy. Dr. Artel, quick question. Microbes and microorganisms are interchangeable, correct? That is correct. So this finally disproved once and for all spontaneous generation. Okay. So the question that he posed was, what causes the growth of microorganisms in the broth? He made an observation. Hey, if I have an open broth container, it's going to be cloudy. If I heat it and cover it, it's clear. And the rest is history. Okay. Now I'm going to talk to you about... this next individual, Robert Koch, the germ theory of disease and Koch's postulates. These are important. The postulates are still used today for the decision on how to treat a certain disease. Robert Koch was a German physician who studied anthrax. We're going to talk about the disease anthrax towards the end of the semester. Towards the end of the semester and the final exam material will... all be diseases. So what my job is to get you ready for that last part of the semester. Okay. So what he did is he studied anthrax in cattle. He discovered a rod shaped bacteria called Bacillus anthracis in the blood of cattle that had died of anthrax. So I'm going to go through with you on how he made that discovery. In doing so, he developed the germ theory. The Koch's postulates is a sequence of experimental steps that verify the germ theory. You need to know the postulates. You need to understand the postulates. And in doing so, he also developed pure culture methods. And I'll explain to you what that means. So what I'm going to do first is I'm going to tell you the beautiful story of the postulates. I want you to just listen. And then we'll go over them again, and then you can take notes if you want, okay? Sometimes it helps to just listen to the story, and then you can write. All right, so here we go. Number one, the first postulate is observation of disease. What that means is that he observed cows that were sick, okay? And those cows that were sick... had the same signs and symptoms and eventually they died. So in other words, observation of disease is the same disease signs and symptoms are observed in all the cases. The animals that do not show signs and symptoms of disease are not sick. Okay. So here we see that in this example, the anthrax disease in cattle, the cattle that were sick had obvious signs and symptoms of anthrax. And they died. Observation of disease. Same signs and symptoms of disease in all that are ill. Number two, cultivation of organism in pure culture. So what he did then is he took a blood sample from the sick animal, the one that was dead, okay, and he cultured it into an auger plate. Now, blood is not one of those things that is supposed to be sterile. We don't want an infection in our blood, okay? We don't want an infection. But blood, let me restate that. Blood shouldn't have bacteria in it. Do you agree? Yeah, that's not one of the sites that should have blood. I mean, sorry, that should have bacteria. But when he took a sample of blood, he was able to culture it into pure culture. What that means is that he found only one type of organism. How do I know that there's only one type of organism in this blood sample that grew? By the color. By the color. It all looks the same. They all look the same. Same color, same size. They look the same, right? This is what you call a pure culture, where you just find one type of organism. So he took a blood sample from the cattle, and he was able to cultivate the organism in pure culture, meaning that there's only one type of organism present. What would be not a pure culture, a mixed culture? Do you see the difference between a pure culture and a mixed culture? I hope so. Right? Yeah. A mixed culture has many different size and shapes, colors, but he didn't find that. So this is important. It is important to get a pure culture because now you find out that, oh, maybe this is what's causing the cattle to be sick, right? So we cultivate the organism in pure culture and only one type of organism is present. That is important. Number three. introduction of the pure culture into an experimental animal. So after he cultured the bacteria on nutrients, he actually injected the sample of the pure culture onto a healthy animal. You see that? Isn't that fascinating? He took that bacteria that he cultured from the sick animal that died and introduced that. into a healthy animal. And then what did he do? He waited. Sorry. He waited and observed that experimental animal undergo the same signs and symptoms of disease as the original animal. So now what? Number four, recovery of the same organism from the experimental animal. Once that animal, the experimental animal got sick, after he introduced that culture, he waited, the animal got sick, same signs and symptoms as the original animal, animal dies perhaps, he takes a specimen of blood from that animal, and then he compares it. This is the bacterial culture from the original sick cow, when he grows it, when he takes the sample from the experimental cow. Look at that. It looks the same. It's a perfect match. Wow, this was mind-blowing. This is the first time that they were able to put or recognize or say, this bacteria causes this disease. That was the first time that they were able to do that. He established a sequence of experimental steps for directly relating a specific microorganism, in this case, Bacillus anthracis, to a specific disease, hence Koch's postulates. So let's review. Number one, observation. He observed the same disease signs and symptoms in all the sick cows. Cows that did not have signs and symptoms were not ill, right? So observation. of disease signs and symptoms. Number two, cultivation of organism and pure culture. He took a sample from the sick cow and he cultured it into pure culture. That is important. If you have a mixed culture, how will you know which bacteria causes the infection? Will you? You won't. You're going to have to go through a lot of cattle, right? So that is why specifically saying pure culture is important. Number three, introduction. He took that pure culture that he cultured from that original sick cow, and he injected it or introduced it into a healthy. experimental cow. Number four, and then he waited and he observed the same signs and symptoms of disease. That is important. That experimental animal exhibited the same signs and symptoms of disease. Number four, recovery of the same organism from the experimental animal. After the animal exhibited same signs and symptoms of disease and perhaps died, then he took a blood sample from that experimental animal, he recovered the same organism as the original. Amazing. Fascinating stuff, right? So Koch's postulate is a scientific method to disprove, sorry, not disprove, to prove causation of disease. It links a specific organism with a specific disease. Why is that important? Because if we know what organism is causing the disease, and maybe we can develop treatments for it because we know what we're targeting. That's why it's so important. And that's why Koch's postulates are still used today to determine what is causing disease. So we can test treatments on cultured organisms in the laboratory. All right. So that is lecture number one completed. Let's continue on. With lecture number two. Any questions. If we need it. Yes, I have a question. So if we need to go back to just review. Where did you say we can find your lecture. Under confer zoom you will find it in events recorded there is a tab. And maybe I'll show you after this lecture, okay? Thank you so much. One second. I want to see you guys again. Meeting info. There you go. Okay. I had a troubleshoot yesterday to try to figure out how to do this. All right. Let me see who else is here. All right. You guys are all there. I'm just checking, viewing. Good. Okay. All right. Let's move on. Lecture number two is going to be the chemistry of microbiology. And there we go. The inorganic portion of this lab, you can review on your own. This is the page numbers that it corresponds in your textbook. Disclaimer, I will not be quizzing you or examining you on this material, but you're more than welcome to review it. if you are interested. And that's when students cross it out and say, do not review, do not read. That's up to you, but I'm not going to examine you. Okay. So this is not a chemistry class, but we do go over basic chemistry. Very, very basic. I'm a double major in chemistry. So I know my chemistry. So what I'm going to teach you is very, very basic. So if you've taken chemistry before and you're like, oh, well, where are the lone pairs and this and that. We're not going to go over that. I'm glad that you know that and you can distinguish that and that you could probably do a better job at it as far as the writing and drawing the correct chemical formulas. But that's not what this class is. This is just to give you a basic introduction so that you understand. Okay? Okay. So let's move on. Common elements in life. All right. So CHOMPS, carbon, hydrogen. Oxygen, nitrogen, phosphorus, and sulfur are elements that are found in all living organisms. Okay? All living organisms. Is there a reason for that order? Just easy to remember. Okay, because I remember there was an acronym that we developed for this called CHENOPS. Oh, CHENOPS. Where's the I? Yeah. Well, there's no I. It's just one of those silly things you remember. Oh, okay. Okay. So I've always used chomps, but you can use whatever, you know, whatever helps you. No abbreviations. You actually need to write out the names of the elements. Okay. All right. So that being said, common elements in living organisms and the number of bonds, basically an atom is the basic unit of a chemical element and atoms are arranged in electron shells. It's like, oh no. Don't worry. It's basic, okay? It's basic. So atoms are arranged in electron shells, and here's what you see, one electron shell, okay? And each shell is going to hold electrons corresponding to the different energy levels. The lowest or the innermost level is going to hold a maximum of two electrons. The second and third will hold a maximum of eight electrons, so on and so forth. We're not going to get past the second electron shell, all right? But here is the key thing. When atoms in the outer shell are filled, the atom is chemically stable or inert. That means they do not react, right? But, you know, atoms want to be stable to a certain degree, okay? Chemically unstable would be an atom where its electron shell is only partially filled. And therefore, if it's partially filled, the atom can react with other atoms. So I'm going to show you how we determined how many bonds an atom needs. Okay? All right. So very basic. Again, it's going to be very basic. All right? So here we have the periodic table. This is where you're going to be writing your notes. You're going to be writing notes. You don't have to have the periodic table in front of you because you'll never use a periodic table in this class. I have it here for demonstration purposes. Okay? So don't freak out. How many of you have ever heard the honk rules? Have you guys heard of the honk rules? Some of you. Maybe no. Yes. No. No? Okay. Good. I haven't. Okay, good. It's good to know so that I know how far to go into it. All right. So, HONC refers to, notice that, well, first of all, it refers to hydrogen, oxygen, nitrogen, and carbon. These are the common atoms that we're going to be working with in this class, okay? Obviously, there's more atoms. I mean, look at the periodic table, yeah? Underneath HONC, I have numbers associated with them, one, two, three, and four. Let me keep tabs of the time because I tend to go over something. One, two, three, four. This has to do with the number of bonds that each of these atoms want to make in order for them to be, quote unquote, happy or stable. Yeah. So it refers to the total number of chemical bonds an atom can form. How do we determine this one, two, three, four, other than memorizing them? You don't have to do what I'm going to show you, but it's for demonstration purposes. But I do want you to write it so that it makes sense to you. All right, here we go. So first we're going to go over hydrogen. How do we know that hydrogen needs to make one bond and only one bond? Okay. If I look at the periodic table, I see that hydrogen has an atomic number of one. Yeah, it has an atomic number of one. We know that the innermost shell of an atom holds how many electrons? Two. That's correct, two electrons. So I'm going to go ahead and Each, the atomic number, this is a number of electrons that it has. So it's one. So it's going to hold one electron. But the innermost shell is supposed to hold two. So is hydrogen happy? No, it's not, right? So how many bonds does it need to make? One. It needs one electron. You see that? In order for it to be stable. And so that's where the one comes. Let's do oxygen. The atomic number of oxygen is eight. Okay. Atomic number is eight. We know that the atomic number is the number of protons, which equals a number of electrons. Therefore, oxygen has a total number of eight electrons. So we're going to distribute those electrons around the oxygen, beginning with the innermost shell, which holds how many electrons? Two. So there's my two electrons. Now I'm going to go to the second valence electron shell. How many total electrons does the second electron valence shell hold? Eight. Eight, right? Okay. But right now I have, so far I have two, right? Two from the oxygen. So I need to get up to eight. So that's, I have two, here's three, here's four, here's five, here's six. Here's seven. Here's eight. Hmm. What's wrong with this? You need two more. Two more. It needs two more. That means that oxygen needs two bonds, needs to make two bonds in order for it to be stable or happy, right? So here are my two bonds, the two electrons that it requires. Therefore, oxygen needs two bonds. Let's go on to nitrogen. Is this making sense? I'm just showing you how do we know that these atoms require this many bonds. Let's move on to nitrogen. Nitrogen's atomic number is seven. Here is my nitrogen right there on the top of the periodic table. That means that that is a number of protons, which equals a number of electrons. So let's go ahead and begin with the innermost shell, which holds a total number of two electrons. Yeah. So I have my two electrons there. I'm going to go to my second valence electron shell, and I'm going to put three, four. Five, six, seven. Is nitrogen happy? Is it stable? No. What does it need? Three more. It needs three more. One, two, three. Therefore, nitrogen requires three bonds in order for it to be stable. Are we getting it? Okay. Let's move on to our final atom, which is carbon. Carbon's atomic number is up here. It is a six. Yeah. So innermost electron shell will hold a total number of two electrons. Here we go. One, two. Second valence electron shell. We're going to put three, four, five, six. Ooh, is it stable? No. What does it need? It needs four. Four more bonds, four bonds or four electrons. So here we go. One, two, three, four. And this is how we get the hunk rules. So I know that carbon will, for our purposes, guys, this is not like organic chemistry that I'm going to get into, okay? For the purposes of this class, microbiology, carbon will always make four bonds. Is that understood? Okay. All right. Now, do I ever require you to do what I just drew here? Never. So here are some of the structural formulas. Okay. This is the chemical or molecular formula versus a structural formula refers to actually drawing it out, drawing it out. All right. So Let's see. Let's do some practice. So get another sheet of paper. We're going to write this down as we go. Now that we know this, now that we know what the hunk rules mean, that means that that's how many bonds each atom needs to make. We're going to go ahead and let's do some practice structural formulas. Yeah, let's do that. Let's draw some structural formulas because they're so much fun to draw. I mean, once you start, you just can't stop. They're really fun. Seriously, you watch. The first thing I do whenever I'm going to do something like this, I write my honk rules, because I don't want to forget. I just don't take it for granted. It doesn't take much space on my paper. I'm going to write honk, and I'm going to write one, two, three, four associated with that, because I just want to remember that this refers to the total number of chemical bonds an atom can form. So if I'm taking a test, I immediately write honk, one, two, three, four, because I'm not taking any chances. It's like a visual. You can double check yourself, yeah? All right, so here's the first one. This is what we're going to be drawing today. The first one is water. Now you're like, water? Really? Everybody knows how to draw water, but have you ever thought why? Yeah? So we're going to start off with our oxygen. How many bonds does oxygen make? How many bonds does oxygen need to make? Two. Two, right? Look at the honk rules. Two. So I'm going to draw my bonds there. One, two. I do my little lines. One, two. Again, we're not going to do lone pairs and all that. Okay, this is microbiology, not chemistry. So we're keeping it simple. Yeah, simple. If you want to draw them, that's fine. You're not going to lose points for it. So there's my two bonds. And oh, geez. Well, what does this two mean in front of the H? There's two hydrogens. There's two hydrogens. Well, that looks like a logical place to put my hydrogens, right? And before I put them, how many bonds does each hydrogen need? One. One. Whoa, look at that. How cool is that? Oxygen is happy because it has its two bonds. And hydrogen is happy because it has its one bond, right? Now let's do methane, the next one. What am I going to start with? What do you think I'm going to start with? Which atom am I going to start with? We don't start with hydrogen. We start with carbon. Now how many bonds does carbon make? Four. Four. So let's draw them. There we go. Well, look at that. Isn't this nice that we actually happen to have four hydrogens that we can surround? Everyone's happy, right? Pretty cool. Let's do the last one. Ooh, nitrogen. This is interesting. How do I do that? Think about that. Before you, if you guys know, don't say, don't say it. Just save it. I know you're waiting to just spit it out. Okay. I'm going to scroll and I want you to tell me, raise your hand if you have no idea how to do this. I'm going to scroll. Everybody knows how to do it? Okay. I don't know how to do it. Okay. I don't either. Okay. All right. I don't know either. Okay. All right. Okay. So let's explore. I have two nitrogens, right? Does that mean that I have two nitrogens? Yes. And how many bonds does nitrogen need to make? Three. Three. Oops. Look at that. It's called a triple bond. That means we can put three bonds together? Yeah. You can do double bonds and triple bonds or single bonds. Yeah. Professor, can you tell me why with the last one you knew that the C or carbon had to go first? Okay. Usually, and this is tricky. That's a good question. And it's tricky because normally we say when we're drawing chemical structures, we often say that you should draw them like you read a word from left to right. But in the case of water, yeah, you wouldn't necessarily do that, right? You start with the oxygen. It has to do with the electronegativity of the atom, but that's beyond the scope of this class. I'm not going to get into that. But normally you would start from left to right, like you're reading a word, okay? If hydrogen is the first atom, hydrogen is just a single bond. You could still draw it if you start with hydrogen, but you might get confused because are you, you know... It's oftentimes when students start with the hydrogen, they connect a hydrogen to a hydrogen to a hydrogen. And then the middle hydrogens have two bonds instead of one. Try it and you'll see what I'm saying. You can draw it with the hydrogen first, but you're kind of, you got to connect it to the carbon. You can't connect them to each other because then you have H2 gas. Hey, professor, I have a question regarding nitrogen. You said there's a triple bond. Is there any chance you could draw that? It's right there. Do you not, you don't see it? No, but I mean, how does it work out? If the outer valence needs six more electrons from both nitrogen atoms. No, no, no, no, no, no, no, no, no. Nitrogen requires three bonds and they bond to each other. Okay, but I don't understand that. Nitrogen, okay, this nitrogen, does it have three bonds? How many, how many electrons does a nitrogen atom have? Total? I guess that's my, yeah, I guess that's my question. Seven. Seven. Oh, okay. I see what you're saying. Okay, seven. Okay, so then you have... So remember the Honk Rules. This is all you need to remember. One, two, three, four. Okay. This tells you how many bonds each of these atoms requires to be stable. Okay? So each nitrogen atom has three bonds. I'm sorry, three electrons. No, each nitrogen atom requires three, needs three extra. Yeah, and so here they are. They're sharing them with each other. So then... I guess I'm a little confused. So then why not just say that oxygen needs, or carbon needs four, well, nevermind, nevermind. It takes some time to process, but you'll get it. We're going to keep it simple, Christian. We're going to keep it simple, just using the HONC rules. I'm never going to give you something really like circular or cyclical or anything really complicated. But what I am going to have you guys do is I'm going to break you up into discussion groups. I want you to quickly introduce yourselves and I'm going to give you about, I don't know, maybe five or six minutes to complete these. I took out one of them that's in your, your, um, that is in your, what is it called? in your PowerPoint. Okay. I took one of them out. So take a look at these, just cross out the, I believe it's urea that I took out. Is that correct? Yeah. Okay. So you can cross out urea and I'm going to break you up into sessions so that you can review this and get to know a little bit of your classmates, put you in breakout rooms. It's going to be random. Whoa, that's a lot of. Whoa. Okay. Talk to each other. Be nice. Okay. I'll see you in a bit. Have fun. How do I know what hoops we're in? You will find out soon, Christian. Don't worry. Okay, cool. Thank you. You'll be okay. Bye-bye. Put your cameras on. I put them in breakout rooms. So they can work on the chemistry really. How was your commotion? I don't know. She's got to eat. She can't have lunch. Come on. Thank you. Thank you. Thank you. Thank you. Don't forget her water bottle. Phil, don't forget her water bottle. Okay, I just don't want you to be hungry later. Okay, get your yogurt then. Okay, then don't eat honey. You're fine. Welcome back. I'm waiting for all these breakout rooms to close. Hello, Professor. Hi. I couldn't go to all the breakout rooms. There were just too many. Okay. Too many, too many. So it was random. All right. Let's see. They're still closing, so let's wait. Not everybody's back yet. Let me put you guys on my other screen. Should we go ahead and mute ourselves now or do that later or what's the deal? What happened? I guess we're back to class. Yeah, you're back in class. Yay. Yay. I was fast. What happened? Jeez. Check our room. The rest of you. Why don't I see the rest of you? It's really hot today. All right. Is everybody back or not yet? Not yet. I'm here. It's like, that's what matters, right? Okay. I'm not trying to say what matter. I'm just trying to say, you know, answer the question. I'm sorry. I don't mean to sound rude. No, no, no, no, no. You're not. You're not. I'm teasing. Okay. It shows that I still have breakout rooms open, but let me see. I'm not sure why I'm not able to close. Can you help me really quick? For some reason, I can't see all the students anymore. It's It doesn't let me open this thing. Oh, here it is. Meeting. There we go. There you guys are. Sorry. I want to see you guys. That's why. All right. Should we show ourselves, professor, or no? Yes, always show yourselves. Okay. I like to see my audience because it helps me. Gage. Okay. Yeah, I can feed off of you guys and, and all of that. Okay, there we go. I don't want to see myself. I want to see you guys. Okay. All right. So, um, why are these people still in the breakout room? I'm closing it. I think that closed it. Okay. All right. So what did you guys think? Was it, did you guys figure it out? Was it difficult? What were your thoughts? It was a little hard. It was a little hard. Okay. Some of you may have had someone that knew what they were doing and that's always a little easier, right? The first time around, it's like anything else. The first time around, it's, it's not, it's, it's really complicated, but afterwards it starts, it starts clicking in my opinion. Good, good. Okay, so let's do it together. And that way you can look at compare it to what you did. And hopefully as I go through it step by step, it will make sense to you. Okay, but if you didn't get it, you were completely lost. Don't worry. This is not a huge part of the class. It's only one small portion of the class. Got it. So don't freak out. All right, let's go. So carbon dioxide. I'm going to start here, actually, with my, oops, I'm going to start with the carbon. Carbon dioxide, right? So carbon, how many? Now, remember, I'm going to write my honk rules, because I always write my honk rules. I want to make sure that I don't forget them. Based on the honk rules, how many bonds does carbon need to be happy? Four. Okay, so this is what I'm going to do. And maybe this is what you did, right? The first thing you do is, well, you write your four bonds, correct? Yeah. Is that what you guys did? Some of you did that? Yeah. Yeah. Right. Okay. So that's good. We're off to a good start here, I think. I don't know. Let's find out. So then what you did is you, how many oxygens do we have? Two. Two. Okay. So I'm going to put my two oxygens. There we go. Now let's, let's ask the question. Is carbon happy? Well, wait a minute. How many bonds did carbon make? Two. It only made two. It didn't make the four. Let's ask the other question. Is oxygen happy? No. No. Because how many bonds does oxygen need? Two. Two. But how many did it get? One. One. No bueno, right? Not good. So what the heck do we do? Double bonds. Double bonds. Ah, that's right. So what if we take away these two little bonds that are not used in the carbon and instead... Are we sharing your screen? Because we can't see your screen. I went through all that work and you cannot even see my screen. Oh my goodness. Well, when were you guys going to tell me that? Let me share my screen. That is not a good thing. Definitely not a good thing. Yeah, let me share my screen. Sorry, guys. Where do I go? You got to love the Zoom thing, huh? This is not fun. It's like learning microbiology all over again, right? Learn something new. Right? It's kind of crazy. Why doesn't it let me? Jeez. And my tech person just left. It doesn't let me get out. Oh. there we go okay i just ended it can you guys are you guys still here yeah i'm still here okay good all right because i don't see you anymore There we go. There you are. Jeez. Let me make this. Hold on. Bear with me. Can you get a whiteboard behind you? It's working there. We can see now. Can you see? Yeah. Yes. Oh man. We already did these. Okay. So here we go. The first thing I'm going to do is I am going to, um, shoot. So we're going to, we're going to take, oh, sorry. Let me back up. So I'm going to start with my carbon atom and we know that carbon makes four bonds. So I'm going to put my four bonds and we said that we have two oxygens. So we put the two oxygens, but nobody's happy, right? So we're going to remove those two bonds that are not utilized there and instead double bond the oxygen. How cool is that, right? So yes, those are double bonds that we just put. Oh, here we go. There you are. Okay. Now, the next one is methanol. And there's a reason that I gave you guys these. There's a purpose for everything I do, even how nutty it may be. So methanol, how do we start with this? Remember that I told you we're going to draw these like we're reading a word. Therefore, we were going to start with what? Carbon. So I'm going to write my carbon. How many bonds does carbon need to make? Four. So I'm going to add my four bonds. Now, what's going to be bonded to this carbon when you look at this? Oxygen. Three hydrogens and an OH. There's going to be three hydrogens, right? Yes? Yes. Well, look at that. How convenient that I have these three bonds on the outside to put each one of those three hydrogens. So I just right now took care of this methyl group. The CH3 is called methyl. I just took care of it. Boom, I'm done with that. All I have left is this OH group. What am I going to do with this third bond for this carbon? Bond it to the OH. The C to the OH. Well, I'm going to bond it first to the oxygen, right? Now, is carbon happy and stable? Yes. Yes, because it has its four bonds completed. And hydrogen, each one of these hydrogens has one bond, just like my honk rules tells me. But is oxygen happy? No. No. Oxygen needs how many bonds? Two. What am I going to bond that oxygen to? Hydrogen. Hydrogen. It's hydrogen. Hydrogen. There we go. You see that? Okay. Now, this next one, ethanol, is a little bit tricky for students sometimes because sometimes when we have chemical formulas, they write them like this. Now, what this tells you is that there are two carbons in this molecule, two carbons, a total of... five hydrogens and then an OH group. Notice, and the reason that I did this, because I wanted you to notice that the OH here, the OH here, and the OH here is separate, is separate and not included. The hydrogens are not included in this bulk. What is that OH called again? Hydroxyl group. Hydroxyl. Okay. Yes. So it's a type of alcohol. These are different types of alcohol. We have methanol. Now we're going to dry. Draw ethanol, and then we're going to draw one propanol. So let's go with the ethanol. We're going to start with what? Another way. So this is one way of writing it. You could write it also like this, CH3, CH2, OH. Or do you agree that with not considering the OH, which is a functional group that we're going to talk about, we have a total of two carbons? Yes. And do you agree that when we add these two hydrogens and these three hydrogens, we have a total of five hydrogens? Yeah. Yes. And that's how we get C2H5. Again, the OH is kept separate. So how do I start drawing this? Carbon. Carbon. I'm going to start with my carbon. I know that carbon makes how many bonds? Four. Four. My four bonds there. I'm going to surround the left side of my carbon with what? Three hydrogens. Three hydrogens. Look at that. That is this first part right there, the CH3 part. I'm done with this part. Let's move on to the second part. What am I going to bond this carbon to? Another carbon. Carbon makes how many bonds? Four. Yeah, four. Here's one. I need to add more bonds to this carbon, don't I? Yes. Yeah. So there's one. There's two, three. Oh, and there's four. I added the two hydrogens before ahead of time. Sorry. So here we see the hydrogens that are there. Sorry, the CH2 right here. Do you see that? Yes. Okay. Now, what is this second carbon going to be bonded to? Oxygen. My oxygen. Oxygen requires two bonds. That only has one. I'm going to bond it to? Hydrogen. Hydrogen. You get that? Remember, get it. Last time you were getting it. Oh, okay, because I wanted to. Okay. Now. The last one here is one propanol. Now that you understand that this can be written like this, you understand what this C3 means. It means that I have how many carbons in my chain? Three. Three. So there is my three carbons. But I know that each carbon needs to make how many bonds? Four. Four. So I'm going to surround it with my bonds. Now, what am I going to fill these bonds with? Hydrogen. Oh, well, I think I need at least seven, right? Yeah. And let's see. I need to have seven. Let's count. One, two, three, four, five, six. Oh, my goodness. Look at that. Is that coincidence or what? Unbelievable. There you go. And what's separate? What's kept separate? The oxygen. The OH group. Got it? Yes. All right. So there's a reason that I gave you these chemical formulas. This right there. And this right there. is often referred to as the rest of the chain. That chain can be 10, 100 of carbon in length, of CH, CH2, CH2, CH2, CH2. That is referred to as the rest of the chain. That doesn't really matter how long it is. You know what does matter? What do you think matters in these two structures? The functional group. The functional group, which is the? Hydroxyl group. The hydroxyl group. So oftentimes what we do is we draw it like this. R for the rest of the chain dash 08. Because R doesn't matter. It doesn't matter how long it is. What matters is that I have my functional group. Got it? And that's why I showed you that. Now that being said here, these are the functional groups that are important. but the ones that you need to know and memorize are the ones that are in your lecture outline. Your lecture outline has all the functional groups that you need to be familiar with. You need to know them. You need to be able to recognize them if I draw them. Got it? Okay. So I'm going to leave it there because on Thursday, no, not on Thursday. Oh, look, here it is. Here's your hydroxyl group. Look at that. Oh, H. They have a dash here because it doesn't matter. Look at this R. Now you know what R means. It means the rest of the chain. Look at here. Look at this one. This is a carboxyl. And R, it doesn't matter what R is. What matters is that I have a carboxyl group. And these carboxyl groups are important because this is where reactions happen. Okay. So I have here when carbon binds atoms other than hydrogens, important for properties of molecules, et cetera. So on Tuesday, we're going to talk about the macromolecules. We're going to talk about the four macromolecules that are important for the body, that are important for microorganisms. Remember, we're going to focus on microorganisms and also our health, right? So the carbohydrates, there is the good carbs, there's the bad carbs. We'll talk a little bit about both. Carbohydrates are going to essentially be your starches, right? your breads, your grains. We're going to talk about lipids, the good lipids, the bad lipids, although sometimes we really do need the bad lipids because it makes the body good. It's what the soul needs, right? We're going to talk about proteins. I love proteins. I'm a protein biochemist by training, so I love proteins and I enjoy to eat them too. Maybe you can give us a little insight into the keto diet. No, we're not going to go there. We're going to stick with microbiology. Oh, come on. This is not a physiology class. All right. And then finally, the last macromolecule that we're going to talk about are going to be your nucleic acids. And we're going to talk about DNA and RNA. So these are the macromolecules. Macro. What does macro mean? It means large. These are large molecules. Large molecules. large number of repeating units, but these units come from smaller units. So on Tuesday, I'm going to show you how do we get these small units called monomeric units and bond them together to make a larger molecule known as a macromolecule. So your homework for this weekend, know and recognize your functional groups. Review the material that we have gone over. so that you are ready for the macromolecule lecture. Okay? Any questions, quick questions? This time is up. Nancy, mute yourself. I mute you. I can mute her. Any questions? Yeah. What did you say? Sorry, go ahead. Go ahead. No, go ahead. Sorry about that. So for the functional group, just pretty much that's what you want us to remember, like the hydroxyl, ether. The ones that are in your lecture outline are the ones that you should memorize, that you should know and understand how to recognize and draw and stuff. Of course, the lecture is important, but I'm specifically telling you, know the functional groups that are in your lecture outlines, okay? Okay. Professor, can I ask you a quick question? Sure. Where do we get this lecture outline? They're also in that same area where you got the lecture. If you look a little bit below that section, why don't you... Well, explore that canvas side, Christian, so that you become familiar with it because under exam one and homework material, all the materials that you need for exam one and all the homework and stuff will be posted in that module. Okay. Okay. Okay. But I guess my question is because I see the lecture one through lecture four or five study outlined and I see homework cell structure and module one summary. I guess my question is where do I go from there? Are we done with lecture? Yes, you are. Yeah, you guys can go because some of you have lab. Thank you. Have a great weekend. Stay cool. And I will see you guys on Tuesday. Bye-bye. Thank you. Bye. Thank you. Thank you. How do I stop recording? Come on, Professor. I have a question for you. Yeah, I know.

Did you guys hear that? Okay. Yeah, I did.

All right. Lecture number one, continuation. We're going to start with the question of the day, which is, what is the three-domain system of life?

And this has to do with the material that we went over last week. I mean, sorry, on Tuesday. So go ahead.

And who wants to answer that question? I'll let you know. It's bacteria, archaea, and I think it was eukarya, right?

That is correct, Richard. Bacteria, eukarya, and archaea. Now, who developed this? His name was like Wills?

That's right. Carl Wills. And this is based on what?

The 16S RNA nucleotide sequence. That's right. It has to do with the 16S rRNA nucleotide sequence because they are all different between those three domains. Okay. So anything, what that means, like someone said, well, how do I know what that is?

What that means is that anything that's living is going to be in one of those three classifications or domains. Within those domains, then we break it down further and further into kingdom, phylum, et cetera. Okay. All right, so let's continue with our lecture. You see my screen, correct?

All right, so what we're going to discuss next is classifying and naming microorganisms, because there is a special way in which we classify and we name our microorganisms, and you need to understand that, okay? So what we call it is referred to as a formal taxonomic system. That is what we use for naming microorganisms. See, Carolus Linnaeus, he was concerned with how do we name organisms?

When we discover something new, what do we call it, right? So he's the one that discovered or developed this. He wanted to have classification.

Make sure you guys mute yourselves. Javon, mute yourself. Thank you.

He wanted to make sure that there was order, that organisms were arranged, whether they were by morphology or... biochemical characteristics, whatever it may be that there was some sort of order. We refer to this naming. Professor, can I ask you a question? Uh-huh.

I'm sorry to interrupt you. I wasn't here in the last class. Where exactly do we get these PowerPoint slides from? Canvas. But we're in Canvas.

Like when I go into modules, which lecture is it? Okay. Do you see under quick links? Go below modules.

Do you see the quick links? Do you see lecture one exam materials? Quick links, lecture one exam materials. Lectures and homework? Yes.

Click on there. It says lecture one, history of microbiology. Is that correct? That is correct. That's lecture one.

Okay, got it. So make sure that you print the lecture lab schedule so that you know which lecture we will be on. Okay?

Okay, got it. All right. Sorry about that.

No, no problem. Okay, so this is referred to as nomenclature. So I'm going to show you today how do you properly write the names of microorganisms. Because this is a prokaryotic class, right? So we're going to focus on prokaryotes.

So let's discuss that. There we go. All right.

So naming a microorganism. The example that I have here is Staphylococcus aureus. Now, again, normally I like to give, I do a lot of chalk talk, but I can't do it in this format.

So that's why I think you will enjoy the videos a little bit more, but I did the best. So whenever you see something written in red, like you will soon, I want you to write that down. Okay. So that's like my board.

So the example here is Staphylococcus aureus. The genus is Staphylococcus. The genus is always capitalized, okay?

And sometimes the name of the organism tells us something about the organism. For example, caucus refers to the morphology of the organism. Caucus or cocci means round, okay? So whenever you hear... the word caucus, you know that this is a round organism, that the morphology, which means shape of the organism, is round.

There's also streptococcus, for example, right? All right. So staphylo means grape-like.

So it's like a little grape-like cluster. And caucus is a shape. So it's a grape-like cluster. Staphylococcus is the genus and it's always capitalized.

The species is aureus. And aureus refers to gold, and it's because it has a sort of goldish look to the pigmentation of the microorganisms. Okay. Notice that the species is not capitalized. It's lowercase.

You need to be very careful because this could be a mistake. When you write the names of microorganisms in your lab manual, I expect proper nomenclature for all the microorganisms that you will write. And we work with a lot of microorganisms. So how do we actually properly write it? Now that we know that genus is always capitalized.

and species is not, how do we write the names of microorganisms if we're writing by hand, like you will in your lab notebook, as opposed to when you're typing your final unknown report? Here we go. Handwritten will be in cursive? That's right.

So handwritten, there are two ways that, no, not handwritten in cursive. There are two ways that you can write it handwritten. Because you don't...

you cannot write in italics, a computer writes in italics, you will underline it. You can write the whole genus Staphylococcus, capitalized, aureus, not capitalized, and you underline it. Or you can abbreviate the genus and write S, capital letter S, dot aureus.

So go ahead and write this down. And you underline it. Notice that in my presentation, I have it in italics because I can use the italics function in my computer.

So if it's typed, I can type it in in italics the way that you see it in the presentation, right? Capitalized genus, lowercase species, or I can abbreviate. the genus.

At the beginning, I don't usually in the lab, I usually don't abbreviate because students are not familiar with the microorganisms yet. There's a lot of organisms that start, that their genus has an S, begins with the letter S, okay? Like streptococcus or serratia or saccharomyces.

So if I put S, you might not know. If I write S. marcescens, you may be like, is that Staphylococcus marcescens? If I write S.

epidermidis, is that Serratia epidermidis? You may not know. So at the beginning, I write the whole name of the organism so that you know the genus and the species. Okay?

So this is the way that I expect you to write the names of the microorganisms. Yeah. Question. I know on Tuesday, you mentioned that you weren't sure if Ms. Morales was collecting lab notebooks. I know for your class, for your lab, you're stating that you are.

That doesn't specifically apply to Morales, right? Because she says she wasn't. I think what she's going to have you guys do is maybe take a picture of a few of your labs and submit it. I'm not sure what she's going to do. But whatever you guys do in your lab, she does things a little bit different as far as the delivery of the materials, but the content will be the same.

So whatever your lab instructor tells you, that's what you're going to do because she's grading your lab, not me. There are lab points associated with the lab notebook. So however she's going to assign those, it's going to be up to her.

Okay? All right. Let's move on. So as I mentioned, the names of microorganisms can be named for a variety of reasons. The example that I gave you was named, it was labeled that way because it helps describe the shape and morphology.

of the microorganism, the morphology rather, and arrangement, which you'll learn the difference between what is the morphology and what is the arrangement. But here we see a number of other microorganisms that were named not necessarily because of their morphology, which is their shape, or arrangement, which is how they congregate. For example, here we see streptococcus, let's see, let's see, let's see, oh, Klebsiella pneumoniae. What do you suppose Klebsiella pneumoniae causes?

Pneumonia? Pneumonia. That's right. So that's why it was named Klebsiella pneumoniae, because of the disease that it causes.

So sometimes the microorganism may be named because of the, you know, to describe the disease that it causes. Sometimes, let's see, like this one, Japanosoma cruzii was named in honor of Oswald Cruz. Now they made it a little fancy and added the end at the end.

but they named it in honor of the person who discovered this. So sometimes then the way that they name organisms is to give you an idea or an explanation of the disease that it causes, maybe the morphology or arrangement of the organism, to honor the scientists who discovered it, or also maybe what it causes or what it forms, like Streptococcus pyogenes. Well, pyo means pus. If you get infected with this organism, you're going to have pus production. So, you know, there's a variety of reasons, not one fits all.

All right, so let's change gears now. And we're going to talk about the history of microbiology. I love history. If I wasn't teaching microbiology, I would be a history professor because I love history. And I like to tell stories.

And I feel like sometimes students may not remember the content, but if they remember the story, hopefully they will remember. the content behind it. Okay. So here we have some of the main historical figures in microbiology, beginning with Anthony van Leeuwenhoek and his discovery of microscopy.

I love history again. And I think his developments were very, very important for his time. Louis Pasteur and his pasteurization, right? He gets credited for pasteurization.

And Robert Koch, who developed the germ theory. Okay, so we're going to begin. These are the main historical figures. There'll be others that I talk about, but these are the main ones.

But let's talk first about Antony van Leeuwenhoek. So he was actually a Dutch, where was he, tailor. He was a Dutch tailor.

And what he did is he developed these lenses, and he would use these lenses to look at the quality of the cloth. Now, he thought it was very fascinating because he was able to see things that he couldn't normally see with the naked eye or he could see it better. And so he started developing these more powerful lenses, if you will, and started getting curious about the things around him. He looked at the stinger of a bee. He would look at pond water.

He looked at the scrapings of his teeth. He looked at various bodily fluids. He was very curious. But what makes this guy so interesting is the fact that he also kept meticulous notes in his notebook. If you take a look at this figure here, look at how descriptive he is in his drawings.

That's how descriptive I want you to be in the lab. You see figure A, it looks like a rod. You see figure B, look how he outlines the movement of figure B. Who knows what the heck that was, right?

Figure G here, you see that it looks like a spirula. We have two rods there. You see he even saw cocci. Cocci are usually a lot smaller than the rods or bacilli. And in figure F, he was very good at differentiating between the different sizes of these bacilli that he saw.

And he even has here what we call a vibrio. This is all terminology that you will become more familiar with. as we continue with the semester.

So this was fascinating. Nobody had ever seen this invisible world. He was fascinated by this and he called these little live microbes animal kills. But this was his actual microscope, the first microscope that was developed.

It was very simple, but it had everything that you need to be able to see. what he was going to see. You see it had the lens, it had the specimen holder, a little focus screw, and a handle. So just like this picture here, he would put it up to his eye against the light to be able to see the microorganisms. Now I have an old microscope.

This was one of the more modern microscopes after the development of his. It's very, very simple. I would put the sample here.

Now it has a little actual sample holder. It has the focusing knob, but I do need a light source and I have to put my eye there. You know, it's more like a museum piece for me. I had a former student that had inherited that from his father and or grandfather or great-grandfather and gave it to me. So that was really, really sweet.

And I really treasure it. So here you see more of his documentation. Just amazing, amazing. But this really rattled the scientific community.

I mean, if you can just imagine, he is posting or documenting information that had never been heard of. What? What do you mean?

There is an invisible world that exists that we can't see? Sorry, that's my co-chair calling me. That is crazy.

Hold on a second. All right, so this rattled the scientific community because now we have this invisible world come to life. Well, what is the big deal? You see, the big deal is that people back then, and this was in the, what was it, the 1600s, right, mid-1600s.

People believed in spontaneous generation. And what that means is that they believe that life arises just, boom, spontaneously. You know, people believe that...

Moist soil will breed mice and toads. That decaying bodies would, you know, automatically give life to flies. That's what people believed. And so when this came about, it was like, huh, so you mean life doesn't happen spontaneously? Life cannot just automatically happen like magic?

Well, we don't know, right? So there was this other belief then, and those people that believed in biogenesis. Biogenesis are those folks that believe that living cells can arise only from pre-existing living cells, that life does not spontaneously occur, all right? So again, after Lew and Hoke's discovery of this previously invisible world of microorganisms, right, the scientific world became very interested in the actual origins of life. So now we're going to talk about the researchers who...

finally put an end or figured out which one is true. What do you believe? In spontaneous generation or biogenesis?

Genesis. Biogenesis? I sure hope so, right?

But remember that spontaneous generation stemmed from Aristotle and that was like what, 300 BC. So this belief of spontaneous generation was acceptable for more than two... 2000 years.

It's not more than 100 years ago that people actually believed that moist soil would breed mice and toads. So it was going to be a very difficult idea to disprove, you can imagine, right? So let's talk about that journey.

Spontaneous generation versus biogenesis. So here we have this scientist, Francois Reddy, and he actually did a simple experiment. He had three jars with three pieces of meat.

One he kept open, one he kept sealed with the cork, and the other one he put a gauze. All right. So the idea is he waited and sought to see what would happen.

What he noticed is that the jar that was open, flies would come in and then maggots would form. He's like, ah, so what happens here is that Maybe life doesn't spontaneously happen, but what happens is that it's these flies that are present and they lay their eggs or whatever on the meat and that's why we have these maggots, right? The other flask, the meat spoiled, but there was no maggots.

And the third one, it was covered so air can go in. Now remember, air is going to be an important factor in this. Air can go in the flask and the flies would try to get there, but no maggots formed because the maggots were not allowed to go inside. All right. Oh my God, I remember this.

So rotting meat, what he found is that rotting meat does not spontaneously produce maggots. That was crazy. That was wild.

The scientific community didn't know what to make of it. So what did they do? They tried to do everything they could to disprove Reddy's experiment. Okay, so this is where we go into John Needham.

Needham was an English biologist and priest. He believed in spontaneous generation. So he conducted an experiment to basically disprove Reddy's experiment. He was not happy with those results. Okay.

And so what he did is he boiled brief gravy and then he tightly sealed it with corks. Days later, it was cloudy. So he showed the scientific community. You see, I boiled the broth.

I even put a cork and it's cloudy. And the only reason that it's going to be cloudy is if there is life. So therefore, spontaneous generation all the way, right?

He believed that there is a life force that causes inanimate matter. What is inanimate matter? Not living, right?

That causes inanimate matter to spontaneously, boom, come to life. Well, this impressed the Royal Society and they elected him a member in 1747. All right, 50 years later or so, we have Spionzani, Lazzaro Spionzani. Now, he was an Italian priest.

Yes, a lot of these scientists and biologists were priests or in ministry and all that, you know, monks, because that's where they had the time and they... had the means and be able to do these kinds of experiments. So that was not uncommon. He was an Italian priest and he contradicted Needham.

So what he thought, what he did is like, hmm, you know what? I think there may have been some errors in Needham's experiments. So I am going to make sure that I'm more thorough with my execution. So what he did is he boiled, he did the same thing.

He used the beef infusion, a broth. But what he did is he boiled it for one hour. We don't know how long John Yadam boiled his. We don't know.

He just said that he boiled beef gravy. So Spagnanzani boiled it for one hour. And then to be sure, he melted the necks of the flasks to seal them, to make sure that nothing would go in. We don't know how tightly he screwed that. cork in his flask, how we know what Needham did.

We don't know that. And what we found, or what he found, is that the flask that Spagnanzani had boiled with the broth remained clear. And unless the seal was broken, it remained clear, you see.

So he did believe that Needham had errors in his experiment. Maybe, like I said, he failed to heat the vials. correctly or well enough or long enough. His seals may not have been tight enough, but more importantly, Spagnanzani believed that all living things come from pre-existing living things.

So do you think that they invited him to be part of the Royal Society? Yes. No. No way.

Nope. Critics claim that there is a vital life force in the air and so by him melting the necks of these flasks didn't allow that life force that's in the air to come in and allow spontaneous generation so no he was not invited what do you say about the eight supposedly there's a certain amount of grams that leave a person's body after the person passes away do you believe there's some type of life force i'm not trying to say i'm a true believer in and all this nonsense. But, you know, some of their, I believe the truth is in the middle.

That's one thing I've always believed. Yeah. Well, I, I'm, I'm right now we're talking about spontaneous generation life coming from pre non-existing non-living things.

You know, when you die, your cells are, some of them are still living and growing or whatever you may call it. I mean, hair still grows, your nails still grow. So there's your vital organs may be deceased, but there are certain cells that may still be functioning, but we'll stay on task. Okay.

So spontaneous generation versus biogenesis. Nope. I think his experiment was valid, but they did not agree. So not until 62 years later, 62 years later, what we have is Louis Pasteur. Louis Pasteur brought a final end to the idea of spontaneous generation, but that's not all he did.

You see, this guy was amazing. He showed that microbes cause fermentation and spoilage. He developed pasteurization, which we will talk about later in greater detail, the different methods and different types of pasteurization.

He developed a rabies vaccine, but arguably one of the most important things is that he disproved spontaneous generation of microorganisms. How did he do this? He used a swan-necked...

flask. Very interesting experiment. What he did is he pour his beef broth, because that was the thing to do, right?

In this long flask, he boiled it long enough to make sure that he killed everything. But before he did that, notice the design of this flask right there. You see that?

How cool is that? And remember that the critics, he didn't seal it. Because remember that one of the criticisms of Spagnanzani's experiment is that by him sealing the flask, he was killing the life force that exists in the air. Correct? Remember that?

Yeah. Yeah. And so what this does is the following. This type of design allows air to go in through the tube and down here. And any microorganisms, because remember that I told you that microorganisms are ubiquitous.

That means that microorganisms are everywhere. So yes, some microorganisms will come and land here, but what will happen is that they're going to get trapped. right there.

See, they'll get trapped right here. And microorganisms that are trapped there, they're not going to, you know, walk up and then down into the broth. They're not going to do that. They can't do that.

They can't climb. They're not climbers. They can fall in there. This is what you actually find still. in a museum in Europe showing Louis Pasteur's swan-necked flask.

So this remained clear, and only if you tipped that flask and reconstituted this pellet of bacteria, then this would become cloudy. Dr. Artel, quick question. Microbes and microorganisms are interchangeable, correct? That is correct. So this finally disproved once and for all spontaneous generation.

Okay. So the question that he posed was, what causes the growth of microorganisms in the broth? He made an observation.

Hey, if I have an open broth container, it's going to be cloudy. If I heat it and cover it, it's clear. And the rest is history.

Okay. Now I'm going to talk to you about... this next individual, Robert Koch, the germ theory of disease and Koch's postulates.

These are important. The postulates are still used today for the decision on how to treat a certain disease. Robert Koch was a German physician who studied anthrax. We're going to talk about the disease anthrax towards the end of the semester.

Towards the end of the semester and the final exam material will... all be diseases. So what my job is to get you ready for that last part of the semester. Okay. So what he did is he studied anthrax in cattle.

He discovered a rod shaped bacteria called Bacillus anthracis in the blood of cattle that had died of anthrax. So I'm going to go through with you on how he made that discovery. In doing so, he developed the germ theory.

The Koch's postulates is a sequence of experimental steps that verify the germ theory. You need to know the postulates. You need to understand the postulates.

And in doing so, he also developed pure culture methods. And I'll explain to you what that means. So what I'm going to do first is I'm going to tell you the beautiful story of the postulates. I want you to just listen.

And then we'll go over them again, and then you can take notes if you want, okay? Sometimes it helps to just listen to the story, and then you can write. All right, so here we go. Number one, the first postulate is observation of disease. What that means is that he observed cows that were sick, okay?

And those cows that were sick... had the same signs and symptoms and eventually they died. So in other words, observation of disease is the same disease signs and symptoms are observed in all the cases.

The animals that do not show signs and symptoms of disease are not sick. Okay. So here we see that in this example, the anthrax disease in cattle, the cattle that were sick had obvious signs and symptoms of anthrax.

And they died. Observation of disease. Same signs and symptoms of disease in all that are ill.

Number two, cultivation of organism in pure culture. So what he did then is he took a blood sample from the sick animal, the one that was dead, okay, and he cultured it into an auger plate. Now, blood is not one of those things that is supposed to be sterile.

We don't want an infection in our blood, okay? We don't want an infection. But blood, let me restate that.

Blood shouldn't have bacteria in it. Do you agree? Yeah, that's not one of the sites that should have blood. I mean, sorry, that should have bacteria.

But when he took a sample of blood, he was able to culture it into pure culture. What that means is that he found only one type of organism. How do I know that there's only one type of organism in this blood sample that grew?

By the color. By the color. It all looks the same. They all look the same.

Same color, same size. They look the same, right? This is what you call a pure culture, where you just find one type of organism.

So he took a blood sample from the cattle, and he was able to cultivate the organism in pure culture, meaning that there's only one type of organism present. What would be not a pure culture, a mixed culture? Do you see the difference between a pure culture and a mixed culture?

I hope so. Right? Yeah. A mixed culture has many different size and shapes, colors, but he didn't find that.

So this is important. It is important to get a pure culture because now you find out that, oh, maybe this is what's causing the cattle to be sick, right? So we cultivate the organism in pure culture and only one type of organism is present. That is important.

Number three. introduction of the pure culture into an experimental animal. So after he cultured the bacteria on nutrients, he actually injected the sample of the pure culture onto a healthy animal.

You see that? Isn't that fascinating? He took that bacteria that he cultured from the sick animal that died and introduced that.

into a healthy animal. And then what did he do? He waited.

Sorry. He waited and observed that experimental animal undergo the same signs and symptoms of disease as the original animal. So now what? Number four, recovery of the same organism from the experimental animal. Once that animal, the experimental animal got sick, after he introduced that culture, he waited, the animal got sick, same signs and symptoms as the original animal, animal dies perhaps, he takes a specimen of blood from that animal, and then he compares it.

This is the bacterial culture from the original sick cow, when he grows it, when he takes the sample from the experimental cow. Look at that. It looks the same.

It's a perfect match. Wow, this was mind-blowing. This is the first time that they were able to put or recognize or say, this bacteria causes this disease. That was the first time that they were able to do that.

He established a sequence of experimental steps for directly relating a specific microorganism, in this case, Bacillus anthracis, to a specific disease, hence Koch's postulates. So let's review. Number one, observation. He observed the same disease signs and symptoms in all the sick cows.

Cows that did not have signs and symptoms were not ill, right? So observation. of disease signs and symptoms.

Number two, cultivation of organism and pure culture. He took a sample from the sick cow and he cultured it into pure culture. That is important. If you have a mixed culture, how will you know which bacteria causes the infection? Will you?

You won't. You're going to have to go through a lot of cattle, right? So that is why specifically saying pure culture is important.

Number three, introduction. He took that pure culture that he cultured from that original sick cow, and he injected it or introduced it into a healthy. experimental cow. Number four, and then he waited and he observed the same signs and symptoms of disease.

That is important. That experimental animal exhibited the same signs and symptoms of disease. Number four, recovery of the same organism from the experimental animal. After the animal exhibited same signs and symptoms of disease and perhaps died, then he took a blood sample from that experimental animal, he recovered the same organism as the original. Amazing.

Fascinating stuff, right? So Koch's postulate is a scientific method to disprove, sorry, not disprove, to prove causation of disease. It links a specific organism with a specific disease. Why is that important?

Because if we know what organism is causing the disease, and maybe we can develop treatments for it because we know what we're targeting. That's why it's so important. And that's why Koch's postulates are still used today to determine what is causing disease.

So we can test treatments on cultured organisms in the laboratory. All right. So that is lecture number one completed. Let's continue on.

With lecture number two. Any questions. If we need it. Yes, I have a question.

So if we need to go back to just review. Where did you say we can find your lecture. Under confer zoom you will find it in events recorded there is a tab. And maybe I'll show you after this lecture, okay? Thank you so much.

One second. I want to see you guys again. Meeting info.

There you go. Okay. I had a troubleshoot yesterday to try to figure out how to do this.

All right. Let me see who else is here. All right. You guys are all there. I'm just checking, viewing.

Good. Okay. All right. Let's move on. Lecture number two is going to be the chemistry of microbiology.

And there we go. The inorganic portion of this lab, you can review on your own. This is the page numbers that it corresponds in your textbook.

Disclaimer, I will not be quizzing you or examining you on this material, but you're more than welcome to review it. if you are interested. And that's when students cross it out and say, do not review, do not read. That's up to you, but I'm not going to examine you.

Okay. So this is not a chemistry class, but we do go over basic chemistry. Very, very basic. I'm a double major in chemistry. So I know my chemistry.

So what I'm going to teach you is very, very basic. So if you've taken chemistry before and you're like, oh, well, where are the lone pairs and this and that. We're not going to go over that.

I'm glad that you know that and you can distinguish that and that you could probably do a better job at it as far as the writing and drawing the correct chemical formulas. But that's not what this class is. This is just to give you a basic introduction so that you understand.

Okay? Okay. So let's move on.

Common elements in life. All right. So CHOMPS, carbon, hydrogen. Oxygen, nitrogen, phosphorus, and sulfur are elements that are found in all living organisms.

Okay? All living organisms. Is there a reason for that order?

Just easy to remember. Okay, because I remember there was an acronym that we developed for this called CHENOPS. Oh, CHENOPS.

Where's the I? Yeah. Well, there's no I.

It's just one of those silly things you remember. Oh, okay. Okay.

So I've always used chomps, but you can use whatever, you know, whatever helps you. No abbreviations. You actually need to write out the names of the elements. Okay. All right.

So that being said, common elements in living organisms and the number of bonds, basically an atom is the basic unit of a chemical element and atoms are arranged in electron shells. It's like, oh no. Don't worry.

It's basic, okay? It's basic. So atoms are arranged in electron shells, and here's what you see, one electron shell, okay? And each shell is going to hold electrons corresponding to the different energy levels. The lowest or the innermost level is going to hold a maximum of two electrons.

The second and third will hold a maximum of eight electrons, so on and so forth. We're not going to get past the second electron shell, all right? But here is the key thing. When atoms in the outer shell are filled, the atom is chemically stable or inert.

That means they do not react, right? But, you know, atoms want to be stable to a certain degree, okay? Chemically unstable would be an atom where its electron shell is only partially filled. And therefore, if it's partially filled, the atom can react with other atoms. So I'm going to show you how we determined how many bonds an atom needs.

Okay? All right. So very basic.

Again, it's going to be very basic. All right? So here we have the periodic table. This is where you're going to be writing your notes. You're going to be writing notes.

You don't have to have the periodic table in front of you because you'll never use a periodic table in this class. I have it here for demonstration purposes. Okay?

So don't freak out. How many of you have ever heard the honk rules? Have you guys heard of the honk rules?

Some of you. Maybe no. Yes.

No. No? Okay.

Good. I haven't. Okay, good.

It's good to know so that I know how far to go into it. All right. So, HONC refers to, notice that, well, first of all, it refers to hydrogen, oxygen, nitrogen, and carbon. These are the common atoms that we're going to be working with in this class, okay?

Obviously, there's more atoms. I mean, look at the periodic table, yeah? Underneath HONC, I have numbers associated with them, one, two, three, and four. Let me keep tabs of the time because I tend to go over something.

One, two, three, four. This has to do with the number of bonds that each of these atoms want to make in order for them to be, quote unquote, happy or stable. Yeah.

So it refers to the total number of chemical bonds an atom can form. How do we determine this one, two, three, four, other than memorizing them? You don't have to do what I'm going to show you, but it's for demonstration purposes.

But I do want you to write it so that it makes sense to you. All right, here we go. So first we're going to go over hydrogen. How do we know that hydrogen needs to make one bond and only one bond? Okay.

If I look at the periodic table, I see that hydrogen has an atomic number of one. Yeah, it has an atomic number of one. We know that the innermost shell of an atom holds how many electrons? Two. That's correct, two electrons.

So I'm going to go ahead and Each, the atomic number, this is a number of electrons that it has. So it's one. So it's going to hold one electron.

But the innermost shell is supposed to hold two. So is hydrogen happy? No, it's not, right?

So how many bonds does it need to make? One. It needs one electron. You see that?

In order for it to be stable. And so that's where the one comes. Let's do oxygen.

The atomic number of oxygen is eight. Okay. Atomic number is eight. We know that the atomic number is the number of protons, which equals a number of electrons.

Therefore, oxygen has a total number of eight electrons. So we're going to distribute those electrons around the oxygen, beginning with the innermost shell, which holds how many electrons? Two. So there's my two electrons.

Now I'm going to go to the second valence electron shell. How many total electrons does the second electron valence shell hold? Eight. Eight, right? Okay.

But right now I have, so far I have two, right? Two from the oxygen. So I need to get up to eight.

So that's, I have two, here's three, here's four, here's five, here's six. Here's seven. Here's eight.

Hmm. What's wrong with this? You need two more. Two more. It needs two more.

That means that oxygen needs two bonds, needs to make two bonds in order for it to be stable or happy, right? So here are my two bonds, the two electrons that it requires. Therefore, oxygen needs two bonds. Let's go on to nitrogen.

Is this making sense? I'm just showing you how do we know that these atoms require this many bonds. Let's move on to nitrogen. Nitrogen's atomic number is seven. Here is my nitrogen right there on the top of the periodic table.

That means that that is a number of protons, which equals a number of electrons. So let's go ahead and begin with the innermost shell, which holds a total number of two electrons. Yeah. So I have my two electrons there.

I'm going to go to my second valence electron shell, and I'm going to put three, four. Five, six, seven. Is nitrogen happy? Is it stable?

No. What does it need? Three more.

It needs three more. One, two, three. Therefore, nitrogen requires three bonds in order for it to be stable.

Are we getting it? Okay. Let's move on to our final atom, which is carbon. Carbon's atomic number is up here.

It is a six. Yeah. So innermost electron shell will hold a total number of two electrons. Here we go.

One, two. Second valence electron shell. We're going to put three, four, five, six. Ooh, is it stable?

No. What does it need? It needs four. Four more bonds, four bonds or four electrons.

So here we go. One, two, three, four. And this is how we get the hunk rules. So I know that carbon will, for our purposes, guys, this is not like organic chemistry that I'm going to get into, okay? For the purposes of this class, microbiology, carbon will always make four bonds.

Is that understood? Okay. All right.

Now, do I ever require you to do what I just drew here? Never. So here are some of the structural formulas. Okay. This is the chemical or molecular formula versus a structural formula refers to actually drawing it out, drawing it out.

All right. So Let's see. Let's do some practice. So get another sheet of paper. We're going to write this down as we go.

Now that we know this, now that we know what the hunk rules mean, that means that that's how many bonds each atom needs to make. We're going to go ahead and let's do some practice structural formulas. Yeah, let's do that. Let's draw some structural formulas because they're so much fun to draw.

I mean, once you start, you just can't stop. They're really fun. Seriously, you watch. The first thing I do whenever I'm going to do something like this, I write my honk rules, because I don't want to forget. I just don't take it for granted.

It doesn't take much space on my paper. I'm going to write honk, and I'm going to write one, two, three, four associated with that, because I just want to remember that this refers to the total number of chemical bonds an atom can form. So if I'm taking a test, I immediately write honk, one, two, three, four, because I'm not taking any chances.

It's like a visual. You can double check yourself, yeah? All right, so here's the first one.

This is what we're going to be drawing today. The first one is water. Now you're like, water? Really?

Everybody knows how to draw water, but have you ever thought why? Yeah? So we're going to start off with our oxygen.

How many bonds does oxygen make? How many bonds does oxygen need to make? Two. Two, right? Look at the honk rules.

Two. So I'm going to draw my bonds there. One, two. I do my little lines.

One, two. Again, we're not going to do lone pairs and all that. Okay, this is microbiology, not chemistry. So we're keeping it simple.

Yeah, simple. If you want to draw them, that's fine. You're not going to lose points for it. So there's my two bonds. And oh, geez.

Well, what does this two mean in front of the H? There's two hydrogens. There's two hydrogens.

Well, that looks like a logical place to put my hydrogens, right? And before I put them, how many bonds does each hydrogen need? One. One. Whoa, look at that.

How cool is that? Oxygen is happy because it has its two bonds. And hydrogen is happy because it has its one bond, right?

Now let's do methane, the next one. What am I going to start with? What do you think I'm going to start with?

Which atom am I going to start with? We don't start with hydrogen. We start with carbon. Now how many bonds does carbon make?

Four. Four. So let's draw them. There we go.

Well, look at that. Isn't this nice that we actually happen to have four hydrogens that we can surround? Everyone's happy, right? Pretty cool. Let's do the last one.

Ooh, nitrogen. This is interesting. How do I do that? Think about that. Before you, if you guys know, don't say, don't say it.

Just save it. I know you're waiting to just spit it out. Okay. I'm going to scroll and I want you to tell me, raise your hand if you have no idea how to do this. I'm going to scroll.

Everybody knows how to do it? Okay. I don't know how to do it.

Okay. I don't either. Okay.

All right. I don't know either. Okay.

All right. Okay. So let's explore.

I have two nitrogens, right? Does that mean that I have two nitrogens? Yes.

And how many bonds does nitrogen need to make? Three. Three. Oops.

Look at that. It's called a triple bond. That means we can put three bonds together? Yeah. You can do double bonds and triple bonds or single bonds.

Yeah. Professor, can you tell me why with the last one you knew that the C or carbon had to go first? Okay.

Usually, and this is tricky. That's a good question. And it's tricky because normally we say when we're drawing chemical structures, we often say that you should draw them like you read a word from left to right. But in the case of water, yeah, you wouldn't necessarily do that, right?

You start with the oxygen. It has to do with the electronegativity of the atom, but that's beyond the scope of this class. I'm not going to get into that.

But normally you would start from left to right, like you're reading a word, okay? If hydrogen is the first atom, hydrogen is just a single bond. You could still draw it if you start with hydrogen, but you might get confused because are you, you know... It's oftentimes when students start with the hydrogen, they connect a hydrogen to a hydrogen to a hydrogen.

And then the middle hydrogens have two bonds instead of one. Try it and you'll see what I'm saying. You can draw it with the hydrogen first, but you're kind of, you got to connect it to the carbon.

You can't connect them to each other because then you have H2 gas. Hey, professor, I have a question regarding nitrogen. You said there's a triple bond.

Is there any chance you could draw that? It's right there. Do you not, you don't see it?

No, but I mean, how does it work out? If the outer valence needs six more electrons from both nitrogen atoms. No, no, no, no, no, no, no, no, no.

Nitrogen requires three bonds and they bond to each other. Okay, but I don't understand that. Nitrogen, okay, this nitrogen, does it have three bonds? How many, how many electrons does a nitrogen atom have?

Total? I guess that's my, yeah, I guess that's my question. Seven.

Seven. Oh, okay. I see what you're saying.

Okay, seven. Okay, so then you have... So remember the Honk Rules.

This is all you need to remember. One, two, three, four. Okay.

This tells you how many bonds each of these atoms requires to be stable. Okay? So each nitrogen atom has three bonds. I'm sorry, three electrons. No, each nitrogen atom requires three, needs three extra.

Yeah, and so here they are. They're sharing them with each other. So then... I guess I'm a little confused. So then why not just say that oxygen needs, or carbon needs four, well, nevermind, nevermind.

It takes some time to process, but you'll get it. We're going to keep it simple, Christian. We're going to keep it simple, just using the HONC rules.

I'm never going to give you something really like circular or cyclical or anything really complicated. But what I am going to have you guys do is I'm going to break you up into discussion groups. I want you to quickly introduce yourselves and I'm going to give you about, I don't know, maybe five or six minutes to complete these.

I took out one of them that's in your, your, um, that is in your, what is it called? in your PowerPoint. Okay. I took one of them out.

So take a look at these, just cross out the, I believe it's urea that I took out. Is that correct? Yeah.

Okay. So you can cross out urea and I'm going to break you up into sessions so that you can review this and get to know a little bit of your classmates, put you in breakout rooms. It's going to be random. Whoa, that's a lot of.

Whoa. Okay. Talk to each other.

Be nice. Okay. I'll see you in a bit. Have fun.

How do I know what hoops we're in? You will find out soon, Christian. Don't worry. Okay, cool. Thank you.

You'll be okay. Bye-bye. Put your cameras on. I put them in breakout rooms. So they can work on the chemistry really.

How was your commotion? I don't know. She's got to eat. She can't have lunch. Come on.

Thank you. Thank you. Thank you.

Thank you. Don't forget her water bottle. Phil, don't forget her water bottle. Okay, I just don't want you to be hungry later. Okay, get your yogurt then.

Okay, then don't eat honey. You're fine. Welcome back.

I'm waiting for all these breakout rooms to close. Hello, Professor. Hi. I couldn't go to all the breakout rooms.

There were just too many. Okay. Too many, too many. So it was random. All right.

Let's see. They're still closing, so let's wait. Not everybody's back yet.

Let me put you guys on my other screen. Should we go ahead and mute ourselves now or do that later or what's the deal? What happened? I guess we're back to class. Yeah, you're back in class.

Yay. Yay. I was fast. What happened?

Jeez. Check our room. The rest of you.

Why don't I see the rest of you? It's really hot today. All right.

Is everybody back or not yet? Not yet. I'm here. It's like, that's what matters, right?

Okay. I'm not trying to say what matter. I'm just trying to say, you know, answer the question. I'm sorry.

I don't mean to sound rude. No, no, no, no, no. You're not. You're not.

I'm teasing. Okay. It shows that I still have breakout rooms open, but let me see. I'm not sure why I'm not able to close. Can you help me really quick?

For some reason, I can't see all the students anymore. It's It doesn't let me open this thing. Oh, here it is.

Meeting. There we go. There you guys are.

Sorry. I want to see you guys. That's why.

All right. Should we show ourselves, professor, or no? Yes, always show yourselves.

Okay. I like to see my audience because it helps me. Gage.

Okay. Yeah, I can feed off of you guys and, and all of that. Okay, there we go.

I don't want to see myself. I want to see you guys. Okay.

All right. So, um, why are these people still in the breakout room? I'm closing it. I think that closed it.

Okay. All right. So what did you guys think?

Was it, did you guys figure it out? Was it difficult? What were your thoughts? It was a little hard. It was a little hard.

Okay. Some of you may have had someone that knew what they were doing and that's always a little easier, right? The first time around, it's like anything else. The first time around, it's, it's not, it's, it's really complicated, but afterwards it starts, it starts clicking in my opinion. Good, good.

Okay, so let's do it together. And that way you can look at compare it to what you did. And hopefully as I go through it step by step, it will make sense to you.

Okay, but if you didn't get it, you were completely lost. Don't worry. This is not a huge part of the class. It's only one small portion of the class.

Got it. So don't freak out. All right, let's go.

So carbon dioxide. I'm going to start here, actually, with my, oops, I'm going to start with the carbon. Carbon dioxide, right? So carbon, how many?

Now, remember, I'm going to write my honk rules, because I always write my honk rules. I want to make sure that I don't forget them. Based on the honk rules, how many bonds does carbon need to be happy?

Four. Okay, so this is what I'm going to do. And maybe this is what you did, right?

The first thing you do is, well, you write your four bonds, correct? Yeah. Is that what you guys did?

Some of you did that? Yeah. Yeah.

Right. Okay. So that's good.

We're off to a good start here, I think. I don't know. Let's find out.

So then what you did is you, how many oxygens do we have? Two. Two. Okay.

So I'm going to put my two oxygens. There we go. Now let's, let's ask the question. Is carbon happy?

Well, wait a minute. How many bonds did carbon make? Two.

It only made two. It didn't make the four. Let's ask the other question. Is oxygen happy?

No. No. Because how many bonds does oxygen need?

Two. Two. But how many did it get?

One. One. No bueno, right?

Not good. So what the heck do we do? Double bonds.

Double bonds. Ah, that's right. So what if we take away these two little bonds that are not used in the carbon and instead...

Are we sharing your screen? Because we can't see your screen. I went through all that work and you cannot even see my screen.

Oh my goodness. Well, when were you guys going to tell me that? Let me share my screen.

That is not a good thing. Definitely not a good thing. Yeah, let me share my screen. Sorry, guys.

Where do I go? You got to love the Zoom thing, huh? This is not fun. It's like learning microbiology all over again, right?

Learn something new. Right? It's kind of crazy.

Why doesn't it let me? Jeez. And my tech person just left. It doesn't let me get out. Oh.

there we go okay i just ended it can you guys are you guys still here yeah i'm still here okay good all right because i don't see you anymore There we go. There you are. Jeez. Let me make this.

Hold on. Bear with me. Can you get a whiteboard behind you?

It's working there. We can see now. Can you see?

Yeah. Yes. Oh man.

We already did these. Okay. So here we go.

The first thing I'm going to do is I am going to, um, shoot. So we're going to, we're going to take, oh, sorry. Let me back up.

So I'm going to start with my carbon atom and we know that carbon makes four bonds. So I'm going to put my four bonds and we said that we have two oxygens. So we put the two oxygens, but nobody's happy, right?

So we're going to remove those two bonds that are not utilized there and instead double bond the oxygen. How cool is that, right? So yes, those are double bonds that we just put.

Oh, here we go. There you are. Okay. Now, the next one is methanol.

And there's a reason that I gave you guys these. There's a purpose for everything I do, even how nutty it may be. So methanol, how do we start with this? Remember that I told you we're going to draw these like we're reading a word.

Therefore, we were going to start with what? Carbon. So I'm going to write my carbon. How many bonds does carbon need to make?

Four. So I'm going to add my four bonds. Now, what's going to be bonded to this carbon when you look at this?

Oxygen. Three hydrogens and an OH. There's going to be three hydrogens, right?

Yes? Yes. Well, look at that.

How convenient that I have these three bonds on the outside to put each one of those three hydrogens. So I just right now took care of this methyl group. The CH3 is called methyl. I just took care of it.

Boom, I'm done with that. All I have left is this OH group. What am I going to do with this third bond for this carbon? Bond it to the OH.

The C to the OH. Well, I'm going to bond it first to the oxygen, right? Now, is carbon happy and stable?

Yes. Yes, because it has its four bonds completed. And hydrogen, each one of these hydrogens has one bond, just like my honk rules tells me. But is oxygen happy?

No. No. Oxygen needs how many bonds?

Two. What am I going to bond that oxygen to? Hydrogen.

Hydrogen. It's hydrogen. Hydrogen. There we go. You see that?

Okay. Now, this next one, ethanol, is a little bit tricky for students sometimes because sometimes when we have chemical formulas, they write them like this. Now, what this tells you is that there are two carbons in this molecule, two carbons, a total of... five hydrogens and then an OH group. Notice, and the reason that I did this, because I wanted you to notice that the OH here, the OH here, and the OH here is separate, is separate and not included.

The hydrogens are not included in this bulk. What is that OH called again? Hydroxyl group.

Hydroxyl. Okay. Yes.

So it's a type of alcohol. These are different types of alcohol. We have methanol. Now we're going to dry.

Draw ethanol, and then we're going to draw one propanol. So let's go with the ethanol. We're going to start with what? Another way.

So this is one way of writing it. You could write it also like this, CH3, CH2, OH. Or do you agree that with not considering the OH, which is a functional group that we're going to talk about, we have a total of two carbons?

Yes. And do you agree that when we add these two hydrogens and these three hydrogens, we have a total of five hydrogens? Yeah.

Yes. And that's how we get C2H5. Again, the OH is kept separate.

So how do I start drawing this? Carbon. Carbon.

I'm going to start with my carbon. I know that carbon makes how many bonds? Four.

Four. My four bonds there. I'm going to surround the left side of my carbon with what? Three hydrogens. Three hydrogens.

Look at that. That is this first part right there, the CH3 part. I'm done with this part.

Let's move on to the second part. What am I going to bond this carbon to? Another carbon.

Carbon makes how many bonds? Four. Yeah, four. Here's one.

I need to add more bonds to this carbon, don't I? Yes. Yeah.

So there's one. There's two, three. Oh, and there's four. I added the two hydrogens before ahead of time. Sorry.

So here we see the hydrogens that are there. Sorry, the CH2 right here. Do you see that? Yes.

Okay. Now, what is this second carbon going to be bonded to? Oxygen.

My oxygen. Oxygen requires two bonds. That only has one.

I'm going to bond it to? Hydrogen. Hydrogen.

You get that? Remember, get it. Last time you were getting it. Oh, okay, because I wanted to. Okay.

Now. The last one here is one propanol. Now that you understand that this can be written like this, you understand what this C3 means. It means that I have how many carbons in my chain?

Three. Three. So there is my three carbons.

But I know that each carbon needs to make how many bonds? Four. Four. So I'm going to surround it with my bonds.

Now, what am I going to fill these bonds with? Hydrogen. Oh, well, I think I need at least seven, right? Yeah. And let's see.

I need to have seven. Let's count. One, two, three, four, five, six.

Oh, my goodness. Look at that. Is that coincidence or what?

Unbelievable. There you go. And what's separate? What's kept separate? The oxygen.

The OH group. Got it? Yes. All right.

So there's a reason that I gave you these chemical formulas. This right there. And this right there.

is often referred to as the rest of the chain. That chain can be 10, 100 of carbon in length, of CH, CH2, CH2, CH2, CH2. That is referred to as the rest of the chain. That doesn't really matter how long it is. You know what does matter?

What do you think matters in these two structures? The functional group. The functional group, which is the?

Hydroxyl group. The hydroxyl group. So oftentimes what we do is we draw it like this. R for the rest of the chain dash 08. Because R doesn't matter. It doesn't matter how long it is.

What matters is that I have my functional group. Got it? And that's why I showed you that. Now that being said here, these are the functional groups that are important. but the ones that you need to know and memorize are the ones that are in your lecture outline.

Your lecture outline has all the functional groups that you need to be familiar with. You need to know them. You need to be able to recognize them if I draw them. Got it?

Okay. So I'm going to leave it there because on Thursday, no, not on Thursday. Oh, look, here it is.

Here's your hydroxyl group. Look at that. Oh, H. They have a dash here because it doesn't matter.

Look at this R. Now you know what R means. It means the rest of the chain.

Look at here. Look at this one. This is a carboxyl. And R, it doesn't matter what R is.

What matters is that I have a carboxyl group. And these carboxyl groups are important because this is where reactions happen. Okay. So I have here when carbon binds atoms other than hydrogens, important for properties of molecules, et cetera.

So on Tuesday, we're going to talk about the macromolecules. We're going to talk about the four macromolecules that are important for the body, that are important for microorganisms. Remember, we're going to focus on microorganisms and also our health, right? So the carbohydrates, there is the good carbs, there's the bad carbs.

We'll talk a little bit about both. Carbohydrates are going to essentially be your starches, right? your breads, your grains. We're going to talk about lipids, the good lipids, the bad lipids, although sometimes we really do need the bad lipids because it makes the body good. It's what the soul needs, right?

We're going to talk about proteins. I love proteins. I'm a protein biochemist by training, so I love proteins and I enjoy to eat them too.

Maybe you can give us a little insight into the keto diet. No, we're not going to go there. We're going to stick with microbiology.

Oh, come on. This is not a physiology class. All right.

And then finally, the last macromolecule that we're going to talk about are going to be your nucleic acids. And we're going to talk about DNA and RNA. So these are the macromolecules.

Macro. What does macro mean? It means large.

These are large molecules. Large molecules. large number of repeating units, but these units come from smaller units. So on Tuesday, I'm going to show you how do we get these small units called monomeric units and bond them together to make a larger molecule known as a macromolecule.

So your homework for this weekend, know and recognize your functional groups. Review the material that we have gone over. so that you are ready for the macromolecule lecture. Okay? Any questions, quick questions?

This time is up. Nancy, mute yourself. I mute you.

I can mute her. Any questions? Yeah.

What did you say? Sorry, go ahead. Go ahead. No, go ahead. Sorry about that.

So for the functional group, just pretty much that's what you want us to remember, like the hydroxyl, ether. The ones that are in your lecture outline are the ones that you should memorize, that you should know and understand how to recognize and draw and stuff. Of course, the lecture is important, but I'm specifically telling you, know the functional groups that are in your lecture outlines, okay? Okay.

Professor, can I ask you a quick question? Sure. Where do we get this lecture outline?

They're also in that same area where you got the lecture. If you look a little bit below that section, why don't you... Well, explore that canvas side, Christian, so that you become familiar with it because under exam one and homework material, all the materials that you need for exam one and all the homework and stuff will be posted in that module.

Okay. Okay. Okay. But I guess my question is because I see the lecture one through lecture four or five study outlined and I see homework cell structure and module one summary. I guess my question is where do I go from there?

Are we done with lecture? Yes, you are. Yeah, you guys can go because some of you have lab.

Thank you. Have a great weekend. Stay cool. And I will see you guys on Tuesday. Bye-bye.

Thank you. Bye. Thank you.

Thank you. How do I stop recording? Come on, Professor.

I have a question for you. Yeah, I know.

Transcript for:YouTube Lecture 1

Transcript for:
YouTube Lecture 1