Transcript for:
Foundations of Microbiology and Microbes

as we begin moving through the microbiology course we're gonna start with just a little overview of the subject of microbiology and give you a little bit of information on what we're gonna study throughout the semester so as we started chapter one the first time we need to think about is the term ubiquitous the term ubiquitous tells us that microorganisms also called microbes are found virtually everywhere as you can see in these pictures this is just a few examples of the different environments in which you can find microbes in the ocean frozen in the RT in the dirt in the air on your skin microorganisms are found everywhere in order to be classified as in microbe the organism must be too small to be seen without a microscope so as we look at these pictures we can't actually see the microbe with the exception of this picture here this is a microscope image but knowing that those microbes are there is really what is interesting about this subject a lot of us may think about microbes as something bad we think about bacteria or viruses that cause disease but in reality most microbes are completely harmless and can actually do good things for us an example of some of the good things that microbes can do for us other than creating oxygen helping make fuels for us microbes are used to ferment food and beverages we would not be able to make things like beer wine bread yogurt cheese for example if we did not understand microorganisms and the process of fermentation so as we go throughout the semester we'll actually learn about fermentation and how that works let's take a brief look at the history of microbiology there's a little argument as to where the subject of microbiology began but most people can credit the first true discussions of microbiology all the way back to the park jeez the poverties did a lot for medicine but what he did for the subject of microbiology was he was the first person to completely dismiss the idea that diseases were caused by supernatural forces now Hippocrates had no idea what was causing the disease but he knew it was not just an act of nature now following this vet Morrow then said you know what I think there's something we can't see that's causing the disease but he still was not the person that discovered microbes microbes weren't discovered until over 1500 years later when Leo and hook the true father of microbiology developed what we consider the first microscope now it wasn't actually a microscope like we no microscopes today it looked more like this picture shown here it was actually just more of a magnification set of lenses and what Leo and Hooke did is he looked at a drop of rainwater and he noticed very small things moving around in the rainwater so late I would hope discovered small organisms still not exactly sure that those organisms were what caused disease but he discovered the first microbes around the same time Robert Hooke and Ben in a microscope and he is who we considered the father of cell theory he discovered the first cell but Robert Hooke was not looking at microbes he was looking at cells within this cork a few other important people in the history of microbiology would be Louis Pasteur he was the person that discovered fermentation and what he was trying to do with fermentation and later on pasteurization was figure out how could we kill the things that were making food and drinks spoiled so what he did he took a flask with a curved neck he boiled it what we now know was occurring was boiling was killing most of those microbes and then with that curved neck once we boiled and killed all the microbes inside of the flask anything coming from the air we get trapped here in the neck of the flask and you would get no growth of microbes so he considered this pasteurization he was heating enough to kill to preserve what was inside of his flask the next experiment he did he boiled the same way but broke the top off the flask now with the exposure to air microbes would enter into this liquid inside of the flask and we would get microbial growth so he was proving that there was microbes in the air that was leading to the spoilage of food and different types of beverages now later on in his research pester also developed some vaccines and we'll talk more about that as we go through this semester the last notable person to talk to you about at this point in the course is Robert Koch Robert Koch developed his postulates the four postulates and what this breaks down to is this man demonstrated that one particular microbe could be the cause of a disease and so he actually took an animal that had died from a particular disease and he was actually studying anthrax he was able to purify from the blood of this diseased animal a microbe that we now know bacillus anthracis the bacteria that causes anthrax it could then take that purified bacteria inject it into a healthy organism this mouse then when the mouse dies he could purify the same bacteria out again proving that it was this one bacteria that was causing the disease now as we continue through the course we will talk more about pasture and Koch and some of your other important people in the history of microbiology but in Chapter one we really just wanted to get an idea some of those important individuals as we go through a microbiology course it's important to keep up with how we classify microorganisms there are three main domains that we use to classify organisms in scientific studies the three different domains are the bacteria which is where most of our microbes will be studying or found the archaea archaea are really odd microbes and then the third domain are the eukaryote you have some microbes in this domain but you also have plants and animals and us within this Eukarya so we're gonna talk about this a little more as we go well we're looking at how to properly name microbes we in this course will use binomial nomenclature to do this we will need to know the genus and species of each organism remembering that the genus is always capitalized while the species is not and then you either need to underline or italicize the scientific name so if we think of a common bacteria that we're all familiar with Staphylococcus aureus so you can see here in this first bullet this is the proper name a proper way to write the scientific name underlined or italicized genus only is capitalized if you're going to abbreviate a scientific name the second bullet here shows you the proper way to do so the genus name is abbreviated with just one letter the first letter and then the species name is spelled out this right here third bullet is absolutely not correct as we look at all of these different microbes throughout the semester in your brain you need to kind of keep an idea of the relative size of what we're looking at so these pictures here on the image show you about the size of an animal on plant sale just kind of a generic one compared to a red blood cell which is smaller mitochondria even smaller would be within the other cells and then a lot of so a lot of your bacteria are gonna be about the size of a mitochondria that you would find inside of an animal or plant so as we go down your viruses are gonna be even smaller than your bacteria so going back to those classification groups are three domains this slide is intended to be just a quick reference for you as you go throughout the semester on the characteristics of these three different domains the most important difference that will follow up with in the next chapter is the difference between the domain Eukarya and the other two domains eukaryote contains eukaryotes which have true membrane bound organelles bacteria and archaea are both you.not cellular prokaryotes which means they are organisms that do not have membrane bound organelles the main difference between your archaea and your bacteria are the type of material that make up the cell wall and again we're gonna cover this more in the next chapter now viruses I have stuck out here over to the sides viruses are unique they're technically are microbes but they are not technically living so now let's spend the last part of this first week going through just an overview of the different types of microorganisms starting with the algae algae can be unicellular or multicellular their cell walls are made of cellulose making them very similar to plants also your algae are majority photosynthetic allowing your algae to be responsible for producing the majority of the Earth's oxygen what makes an algae different from a plant mostly is the fact that they can be unicellular more simple and they are microbes ouchy are important in our everyday life they help us produce oxygen they're using the laboratory setting in the form of auger you have auger in your refrigerator right now you purchased it in your lab kit but somewhere you may not think algae are found in ice cream salad dressings lipstick toothpaste all sorts of things you use every day our next wave of micro organisms are the protozoa these are really neat and probably some of my favorite microorganisms they can be unicellular or multicellular they are highly motile meaning they can move and they're classified by which type of organelle they used to move they can have cilia flagella pseudopods some of your protozoa can be parasitic cause some pretty nasty diseases but then other protozoa are gonna be found in your drinking water and if you've ever ran water from the tap and took a sip you've drank of protozoa and you're all still alive so you're okay the third group of microorganisms will study this semester are the fungi they can be unicellular or multicellular the microscopic groups include yeast and molds not gonna be studying mushrooms we're studying the microscopic all cell walls of fungi are gonna be made of chitin making them completely different from plants and algae almost all types of fungus are going to be free living and completely harmless but there are a few types of pathogenic groups that will go through we get through this semester the largest of the microbes are gonna be the helmets helmets are parasitic worms they are included in the microbe group because they are transmitted from one host to another during a microscopic stage so this particular picture this is a several foot long tapeworm that was taken from someone and then our last group of microbes are the viruses as I said they are not composed of cells they're completely a cellular they are obligate intracellular parasites all of your viruses are parasites so just to close the goal of chapter one was really to give you an overview of the different types of microbes and what we're going to be studying this semester will really get a good start with our bacteria remember those are the ones that do not have membrane bound organelles and that will move in through those different eukaryotic microbe groups