Transcript for:
Anatomy of Prokaryotic and Eukaryotic Cells

[Music] so we're going to take a look at the functional anatomy of prokaryotic and eukaryotic cells to start out guys we're going to start doing a comparison where we're going to look at different structures and how they relate to prokaryotic cells and eukaryotic cells now when we're focusing here on the prokaryotes we're going to be focusing in on the domain bacteria when we look at bacteria their dna is not found in a membrane-bound structure it's going to be found in a general area called the nucleoid we also see that their dna is going to be in a single circular loop so they only have one chromosome and it's going to be in a circular loop now in the picture it may not appear to be of one single loop but it's going to be wound up in that area of the nucleoid when we look at the dna in eukaryotes it will be found in a centralized structure called the nucleus and it will have a membrane around it in the case for the eukaryotic cells we do see that they have more than one chromosome that's where the s comes in they have chromosomes and it is associated with these special proteins called histone proteins okay so where the chromosomes actually wrapped around these special protein structures with organelles prokaryotic cells do not have any membrane-bound organelles they're actually very they're relatively simple internally in the fact that they don't have a lot of these structures they do however have ribosomes present and if you recall ribosomes are important because they do protein synthesis in the case of prokaryotic cells these ribosomes are going to have a 70s structure and we will talk about what that means a little bit later when you go to eukaryotic cells they are going to have various organelles now organelles mean little organs which means they have a lot of structures that are going to do different jobs these are membrane bound they also will have ribosomes but their ribosome structure is a little different and it has an ads structure when it comes to cell walls prokaryotic cells do contain a cell wall and normally these prokaryotic or bacterial cells are going to have peptioglycan found in their cell wall structure now peptidoglycan is a very complex structure compared to the cell walls that we see in eukaryotic cells now not all eukaryotic cells have a cell wall animal cells do not contain a cell wall plant cells do and they have the structure of having it as cellulose and fungi have a structure of chitin and you can see that in the picture here you'll notice that this chitin or chitin structure is not as complex as the peptioglycan that you see for the bacteria so a little concept here is that all cells do have a plasma membrane okay the plasma membrane is the barrier of the inside of the cell versus the outside of the cell but not all cells contain a cell wall all right so now we're going to look at cell division in prokaryotic cells the cell is going to go from one cell to two cells and this process is going to be known as binary fission now with binary fission it is asexual reproduction because it does only start with one parent now the two cells that come out of this particular procedure or process are going to be exactly the same as the parent cell now eukaryotic cells also do a form of asexual reproduction where they go from one cell to two but theirs is through mitosis mitosis actually means division of a nucleus and so since the eukaryotic cells have a nucleus and it needs to divide that is why it's called mitosis for them and binary fission for prokaryotic cells because prokaryotic cells do not contain a nucleus so again asexual reproduction produces daughter cells and those daughter cells are going to be identical genetically to the parent cell that we start with mitosis does involve the division of the nucleus and this is why it happens in eukaryotic cells whereas prokaryotic cells are going to use binary fission since no nucleus is present now for prokaryotic cells in cell organization they tend to be less complex and smaller in size because of this and organisms that are in this group are going to be unicellular when we look at eukaryotic cells they are more complex and this is due to the fact that they have all those organelles that are present most are actually multicellular now of course there is the exception in the kingdom protista but the cells of eukaryotes are normally about 10 times larger in size in this of the cells of prokaryotes all right so we're going to mostly focus on prokaryotes in this particular presentation we'll focus more on the eukaryotic cells a little bit later in another presentation so with prokaryotes this is the domain archaea which none of them cause disease so you're not going to hear about them much throughout the course and bacteria now it is important that we id the type of bacteria by cell shape and arrangement so when we're looking at shapes there's going to be a series of shapes that we're going to be looking at and there's three kind of main groups for the most part we have the round shaped cells these round shaped cells are known as caucus cells and i have a little o highlighted there so that you see that it's round okay so these are the round shaped cells and when we talk about the word caucus here it kind of means berries we then have a type of rod shape this is known as the bacillus and so i have the two l's highlighted to show you the rod shaped alright so we have that bacillus group now you'll notice they're not all exactly the same shape rod wise some of the even look like little drumsticks or whatever but they do have that rod shape the last group are going to be the helical the ones that look like a spiral and so these are going to be spirulium now spirulium are going to be more rigid in their structure whereas spirochetes are going to be more flexible also in this group there is what we call the vibrio and vibrio have a comma shape to them so this is what we're looking at for the shapes now what about arrangement now if you look in this particular diagram you're going to notice that these are all cockeye cells so they're going to be all round cells so let's look at some arrangements that these cells can undergo we see that they can have the diplo this means they're in pairs where two of them are together so we would call this diplococci because this tells us there's two and they are those round cells we also have the strepto strepto means it's in a chain and if you look here we have a chain of those circular cells so this is streptococci now sometimes they'll come in these kind of packets or groups and we see that the tetrad is going to be in fours and a sarcanee is going to be in cubes or octets the last one is staphyloe and staphylomeans grape-like clusters and so in this case you have a cluster of these round cells so it's called staphylococci now these may kind of sound familiar if you've heard of somebody who had a streptococcus infection this is what it looks like underneath the microscope if they have a staphylococci infection that's what we're looking at there down at the bottom so this gives us an idea of what cells are present but also the arrangement now a quick thing to note though guys that organisms that are grown on artificial media like in the plates in the lab they may not typically exhibit this cellular arrangement they may not get into their strepta or their staph flow as well as if you were to take the sample straight out of it from a living organism so you may not see streptococcus actually in chains when it's grown on artificial media the same thing with staphylococcus you may not see them in the clusters as much so you'll notice here that you'll see that this is one gram staining from an auger plate you'll notice that they look very similar okay in that structure versus if you look at the other two pictures that were out of the living tissue sample you can see that there are some differences you see the chains versus the clusters all right so now using the information that we've already gone through describe the following by gram reaction so is it gram positive or gram-negative the morphology so that's telling you the shape of the cells and then the arrangement of the cells okay so you've got to be able to do this okay when you're going through this course so in this first example we see that these are gram positive we know they're gram positive because they are purple okay so we're looking at the smaller cells here because bacteria is smaller they're prokaryotic cells and so these are going to be gram positive if you'll notice they're in twos so that's the diplo and they are circular so that's the cockeye so this is gram positive dippolo cockeye the next one because it has a pinkish red color this one's going to be the gram negative again they are in pairs and they have kind of this roundish structure so in this case we have gram negative dippolo cockeye the last one is gram positive again it is purple in color and it's going to be the cockeye and chains and so since the cockeye is in chains would say that it is streptococcus so when we look at this guys we need a din a definitive eye a definitive idea of the bacteria cannot be made solely on the gram reaction in the morphology okay we can't go through the process and be like oh that is what that particular one is we've got to have to do further tests to find out the reason being is when we look at this gram-positive diplococci is it streptococcus pneumoniae well wait a minute the strepto tells you it should be in chains okay but is that what we're looking at the gram-negative diplococci is it an assyria gonorrhea don't know we have to do some further tests and of course then the last one it could actually be enterococcus not streptococcus when we're talking about it as a species all right so it's important for us to do more tests in order to figure out what potential bacteria we're looking at all right so when we move on to the bacillus group in the sense of the rod shaped cells their arrangements are going to be a little bit different okay so we see that these terms are typically not used to describe cellular arrangements for bacilli we don't normally use diplo bacilli and streptobacilli when we're describing things like we did with the caucus group all right but they are present they can be in twos or in in um chains we also see that sometimes if they have kind of a shape that's similar to cockeye but also bacillus we give it that name calciobacillus because it's kind of a mix of the two now guys one thing that's important here is the term bacillus is used to describe cellular morphology but it is also going to be used to describe some species and these are called the bacillus species if you'll notice though there is a difference when we're talking about a particular species what do we have to do with that name we have to capitalize it okay so that genus bacillus is capitalized so this tells you we're talking about something specific not just the general cellular morphology all right so describe the following by gram reaction morphology and arrangement okay so in the first one we have that purple color so these are going to be gram-positive bacilli they kind of have a box car shape okay but these are gram positive bacilli the next one is also purple and these are gram positive bacilli but you'll notice these are in chains we're not going to call that streptobacilli but they are in chains now if you'll look at these two that we have here you'll see that these are considered monomorphic now monomorphic means you have a single shape that's present within the culture on the other hand over here we have gram positive but we have we call it uh polymorphic bacillus this is described as using as looking like kind of chinese letters or clubs like in palisades which are like evenly distributed cells a lot of times these are also called diphthroids an example of these are going to be korani bacteria all right so now we're going to actually take a look at structures that are going to be present in some of the bacteria that we will be studying now these structures we're going to start with are going to be on the external part of the cell wall the first one is what we call a glycocalyx now glycocalyx is a caps can be a capsule the capsule helps with virulence and a capsule is firmly attached to the cell wall on the other hand we can have a slime layer also out here it's a type of glycocalyx and it's only going to be loosely attached to the cell wall so if you'll take a look here at this picture we have the inner plasma membrane in the yellow we have the middle cell wall area that's in the green and then we have the outer capsule which is the orange in this case it's firmly attached to the cell wall now this is a gelatinous kind of sugar coat around the bacterium cell and it protects the cell from being engulfed this is going to help protect it like from your immune system your immune system is maybe going to have a harder time holding on to it because of this this gelatinous type of structure that's around the cell an increased virulence factor means that it has an increased chance of making you sick it has an increased chance of being pathogenic now sometimes there's what we call a k antigen the k antigen is a capsular antigen and this actually induces an immune response in some cases what types of staining allow us to be able to see capsules we talked about this in the previous presentation so what type of staining is this this type of staining is the negative staining technique so guys here's some examples of some bacterium that are going to have that gelatinous capsule to it and you can actually see it when they're growing on the plate you can see that it has more of a jelly like substance to it or texture to it klebsiella pneumoniae on the mcconkey's auger over here and we have also streptococcus pneumoniae on the sheep blood auger okay the five percent sheep blood auger so it shows you how they're growing so the colonies kind of have this mucus like structure to them so mucoid-looking structure some virulent strands of bacillus anthracis is also going to produce a capsule the next one we want to look at are the flagella the flagella are going to help with motility movement now these are associated with an h antigen and so when you see examples like with this e coli where it says e coli survivor o 157 h7 the h is referring to the type of flagella antigen that's present okay so it could be different based on like mutations that can occur even within different subgroups of the of a bacteria like e coli so the first flagella we're looking at is going to be the peritricus type of flagella and that is going to be where there are many flagella and they're all over the organism we then have the monotrochos and what also is called polar so when it's a mono it tells you that it only has one and polar tells you it's on one end the lophotricos are going to also be many but they're also going to be contained in one area and so that's again where the polar is located so it's going to be on one end the amphotercosis are also going to be polar bacterium and you're going to see the flagella on both sides okay so on both poles the flagella will be present now a lot of times guys with this flagella it it helps it move and it does it by rotating and the flagella can either rotate clockwise or counterclockwise we also see that there could be axial filaments for motility these are going to actually run and wrap around the whole body of the bacteria this is actually what you see in spirochetes okay in that spiral type shape and this is what allows it to move more of like a corkscrew type of movement an example of this is treponea pallidium which causes syphilis we also call a lot of times these axial filaments endoflagella because the fibrils wrap around the cell and lays within the outer sheath of the cell another structure that we want to look at are what we call fembre fimbre are going to have two kind of functions for one they're going to help with adhesion and holding on the bacteria being able to hold on to something as well as a sex pillis and guys the sex pill is part of the fembra is going to help transfer genetic information from one bacteria to the next remember they're going to reproduce by asexual reproduction which means they all would be the same but mutations do happen or they pick up pieces of dna that help them and then they can pass them on to bacteria that are nearby now fimbre guys are going to be bristle-like fibers that extend out from the cell a cell may have 200 to 400 of these and it allows them to attach to surfaces now when we look at this it acts kind of like a velcro in that sense so it allows it to attach when we look at the sex pillows it has more of a tubular structure it will be longer than your normal fembrae okay and we do see that they'll have none or less than 10 of these and the whole point of this is again for genetic information transfer and that is called bacterial conjugation if fimbre is present it's associated more often with gram negative organisms so some examples would be things like e coli necessary gonorrhea the next one we want to look at is the cell wall the cell wall protects the plasma membrane and also provides and gives shape to the cell now this cell wall can be gram positive which we talked to talked about previously if it's gram positive it's going to stain in that purple color due to crystal violet and it's going to have a thicker layer of peptidoglycan which you can see here in the picture gram negative on the other hand is going to have a thinner layer of peptidoglycan it's also going to contain an outer layer of what we call lipopolysaccharides now these lipopolysaccharides also referred to as lps are going to be important because a lot of times they are going to produce endotoxins now an endotoxin that could be released is called lipid a and it gets released when the cell dies so what happens here is that the cells the kind of making you sick and it triggers your immune system and then your immune system attacks it and destroys it but the bacteria is like oh wait a minute i got something else for you you destroyed me but i'm going to get the last laugh because i'm going to release this endotoxin which is going to cause you some more problems okay and so again it's a virulence factor but it's going to be a toxin found inside of the cell wall and when the cell wall ruptures the toxin comes out another one is an o polysaccharide the o polysaccharide is kind of antigen and again it can have us it can help us be able to distinguish different subtypes of a bacteria like with e coli so that o157 is referring to the type of polysaccharide that is present here now remember gram-negative bacteria are going to stain more of the pinkish color because they are not going to hold on to the crystal violet due to the decolorization in the gram stain and they are going to take in the secondary stain which is the safranin another thing that is important with these gram-negative bacterias is because they have the peptioglycan with this lipopolysaccharide structure the lipid polysaccharide structure actually helps act as a better barrier than just the peptioglycan and it protects against detergents heavy metals and bile salts and so it's going to cause it to be harder to potentially treat because it's going to be harder to access even less some antibiotics have a harder time working on gram negative bacteria when we go back over here to this endotoxin that could be released remember i told you it's kind of the bacteria gets the last last laugh it's like hey you killed me but i'm going to still cause problems some of those problems that like lipid egg can cause are going to be things like fever they could send the person into shock and blood clots now another type of bacteria that we need to look at are called mycoplasma mycoplasma is the causative agent of walking pneumonia and they are a type of bacteria that's kind of an exception to the rule remember earlier we talked about prokaryotes and bacteria pretty much all have a cell wall well mycoplasms do not they lack a cell wall they're the smallest living microbe that's out there and they have a high lipid content and this lipid content contains a lot of sterols in their plasma membrane mycobacterium also has that high lipid content and this is going to be what we call that my myclonic acid now remember with the myclonic acid we have to stain it with a different type of stain gram stain doesn't work and we have to use that acid fast now rka remember is not talked about much here and one reason why archaea bacteria were moved to different groups is because their cell wall structures were so different another note is that some antibiotics they actually interfere with cell wall synthesis they interfere with the bacteria making the cell wall that it uses for protection penicillin affects those cross bridges that are found in the gram positive bacteria of that peptidoglycan cell wall but penicillin does not work near as well on gram-negative bacteria so bacteria cells with atypical cell walls do not gram-stain well okay so if their cell walls are different they don't grab stain real well different antibiotics have to be used on gram positive versus gram negatives because of the structural differences that are present and damage of the cell wall can lead to osmotic rupture of the plasma membrane guys if we can poke holes in our cell wall it makes that bacteria more vulnerable and it makes it where it's more vulnerable to losing water and or gaining water and it can cause the the cell to rupture all right so let's do a quick comparison here of gram positive versus gram negative when we look at the gram reaction we see that it's going to retain the crystal violet with gram positive and it's going to take the counter stain of safranin if it's gram negative the peptidoglycan layer is thick in gram-positive it's thin in gram-negative when we talk about the periplastic space or outer lipopolysaccharide the release of endotoxins we see that that is absent in gram-positive bacteria but in gram-negative these are present and they release that lipid a endotoxin now sensitivity to what we call lysozyme which is a which is a natural type of antibiotic that is made mostly like in your tears and some of your bodily fluids as well as penicillin gram positive responds very well to it it actually can be destroyed pretty easily and weakened by lysozyme and penicillin gram-negative however its response or sensitivity is low now resistance to drying out gram-positive has a high resistance to drying out but gram negative does not now this means that if they are able to not dry out as quickly they can actually be in the environment for longer and be on surfaces longer so gram positive bacteria can survive on surfaces longer because they're not going to dry out as quickly as you see the gram negatives all right so this brings us into plasma membranes now the plasma membrane is also known as the cell membrane or the cytoplasmic membrane and we see the structure of the plasma membrane is kind of like a fluid mosaic model so guys when we talk about a fluid mosaic model it is a phospholipid bilayer meaning there's two layers of those phospholipids where they have the heads and the tails it does create this fluid type of structure it's kind of like a lipid see a fat c here the mosaic part is telling you that there's a bunch of stuff that is embedded within this membrane and in this case it's going to be mostly proteins when we talk about bacterioplasma membranes they actually do not contain certain structures like animal plasma membranes contain they don't contain the glycoproteins the glycolipids or the sterols okay except for the mycoplasm that we talked about earlier they do retain however the integral proteins the peripheral proteins and the surface proteins so they contain still all those protein structures they just don't have the others now remember when we have this phospholipid bilayer the head of the phospholipid is hydrophilic liking water the tells however are hydrophobic so what are the functions of this plasma membrane the plasma membrane acts as a barrier between internal and external environments it is subject to rupture if it's not protected and so this is why bacteria really wants that cell wall the cell wall helps protect it from rupturing the other part of function of the plasma membrane is for transport it's going to allow the movement of substances into and out of the cell now it's not just going to let anything move in and out something that's really important about this is it is selectively permeable it's going to pick and choose what gets to move in and out of the cell a lot of times i compare it to like a bouncer of a club like one of those high-end clubs you have the big line of people they're gonna pick and choose who gets to come into the club okay that's kind of how the cell membrane is gonna work because it wants to bring in the things that are beneficial to the cell and it wants to get the things out that it needs to get out of there whether it's waste products or things that's made that need to be released okay so it's going to be selective on what gets to move in and out when we're talking about bacteria cells the plasma membrane is where aerobic cellular respiration is going to occur cellular respiration guys is how the cells create atp and for us that happens in the powerhouse of our cell which is the mitochondria remember bacteria though don't have organelles they don't have mitochondria so they are going to have special proteins embedded in their membrane which are going to allow them to do cellular respiration all right let's talk a little bit about this transport of moving in and out of the cell now there is what we call active transport active transport is going to be where atp or energy is required to move substances and the reason why atp is required is because we're going to try to move substances against their concentration gradient because most substances like space just like us we like our personal space okay so do molecules so if they're tightly packed together those molecules want to spread out okay and the idea of spreading out is they're going to go from high concentration to low concentration well in active transport we are going to push them back to the high concentration we're going to push them where they don't want to go which means that it requires energy it's kind of like if you've ever seen a parent or a person deal with a toddler who does not want to go somewhere that parent has to utilize a lot of energy a lot of times to move that child because the child acts as dead weight okay and so that's kind of what's happening here is the cells having to use energy and push it to the area it does not want to go passive transport on the other hand is no atp required whatsoever this is just letting the molecules move from high to low okay where they're spreading out this is like getting in the lazy river at a water park you get in you don't have to do anything the current does all the work for you okay and that's what it's looking at for passive transport so guys here are a lot of examples of passive transport the first one is what we would call simple diffusion molecules are just moving across that plasma membrane from high concentration to low concentration okay they have no they don't need any kind of help they can just do it through the membrane however some molecules are either too big or they have a charge that makes it harder for them to move across the membrane and they need some help in that case they're going to use those transport proteins that are embedded in the membrane that's called facilitated diffusion they're going to get some help but again still no atp is required because it's still moving from high to low the last one over here is the movement of water and the movement of water from high to low the diffusion of water is called osmosis now why do we need to talk about this and specifically that movement of water well osmosis is movement of water from high to low okay so it has a concentration gradient against that plasma membrane that selectively permeable membrane now when we put cells in different solutions we call that tonicity the tonicity of a solution describes the solute's concentration and it is relative okay so in this particular case we have a hypertonic solution okay the blue solution has tons of little green guys in there okay those are the solutes that are placed in there okay so there's a lot of them so this is hypertonic more solutes less water the cell then however is hypotonic because it has less solutes on the other hand this picture is showing you a hypotonic solution because there's only one little solute in it versus the cell which is hypertonic if it's the same there's equal amounts on both sides we call this isotonic it's the same now again why is this important well guys water is going to move from a high concentration to a low concentration so in the case guys water is always going to flow from the post side to the per side it's going to flow from the hypo to the hyper so in this case water is going to go out in the first picture this is going to cause the cell to shrivel up and shrink that cell then could die and not continue to do its job in the second picture the water is going to go into the cell this could cause the cell if it doesn't have that protection of the cell wall it could cause the cell to expand and eventually burst okay now in the third one with it being isotonic the water is just going to move back and forth at an equal rate okay no change to the cell is going to occur now cells placed in isotonic solutions have no net movement of water across the membrane so water will move but if five mo move in five move out ten move in ten move out there's no net gain or loss but cells placed in a hypotonic solution will swell and osmotic lysis could occur if that cell wall is damaged in in bacterial cells this is why taking certain antibiotics or lysozyme activity is important because if it pokes holes in the cell wall then your body can use this structure in order to cause the cell to burst on the other hand if a cell is placed in a hypertonic solution it will shrink up and this is called plasmolysis you can see that the plasma membrane is pulling away from that cell wall structure again the cell can be rendered useless here and it could die so an application well this whole idea of water and the movement of water in different solutions could control microbial growth in order for bacteria to grow properly they need perfect osmotic conditions so this is why when we do cultures and we want to grow it in the lab we need to give those good conditions on the media bacterial cells in a hypotonic and hypertonic solution are subject to becoming metabolically inactive therefore they can't be utilized anymore they can't continue to do their job because their metabolism has stopped all right so some other structures we want to take a look at this is moving into the cell we have the cytoplasm the cytoplasm is composed mostly of water with a variety of inorganic and organic substances it's an aqueous solution and it's going to end up bathing the whole dna area that nucleoid and this is also where the ribosomes are floating in the cell the nucleoid recall is the region or the location of the single loop of dna now remember since this is still dna deoxyribonucleic acid it is still double stranded it has the two sides the twisted type ladder structure to it sometimes those these bacteria will have small pieces of dna that are not actually connected to that single chromosome in the nucleoid these are an accessory ring of dna and these are called plasmids these are not crucial for the metabolism of that particular bacteria but they're extra genes and these extra genes could be donated through that sex pilus we talked about from one cell to the other these can be responsible for antibiotic resistance guys this is how they share that when one's like hey i don't get i don't get destroyed by that antibiotic do you want protection and the other cells like yeah it gives a piece of that dna and it helps spread that this is also how some of them start producing toxins and other virulent factors that cause them to be more a little more dangerous we also use plaid plasmids in biotechnology when we want to do gene manipulation and transfer okay so we are taking what they automatically do and we're we are manipulating it and using it in a different manner all right let's talk a little bit about these ribosomes ribosomes remember are responsible for protein synthesis and they are made up of two subunits they have a large unit and a small unit now one thing that is really important is the fact that our ribosomes are different than the ribosomes found in bacteria this allows for the use of certain types of antibiotics we talked about some antibiotics mess with the cell wall which is fine because in animal cells like us we don't have a cell wall so it's specific against the invader and not us but what if we want to attack the ribosomes we have ribosomes and so do they well our ribosomes are a little different antibiotics can be used to target that 70s structure versus the ads structure that our ribosomes have so if you take a look at the prokaryotic ribosomes they're a little bit smaller they have a 30s small unit and a 50s large unit when those combine they make a 70s unit you're like wait a minute that doesn't add up i'm not even sure why they don't add up that way except for that when they come and combine together their sedimentation rate just does not equal what it did before now sedimentation means when they're spinning it in a liquid how quickly does it pull and fall to the bottom hey look how heavy is it in that sense in that liquid in eukaryotic cells our ribosomes are larger our small unit is 50s our large unit is 60s and when those combine it makes it 80s so these are unaffected by the antibiotics so again when we talked about medication and chemotherapy it's important for medication to be specific in order to be effective so these antibiotics are going to trigger or going to attack the 70s unit but they don't attack ours they don't attack those ads units so our cells can still make proteins but the bacteria cells cannot another structure that bacteria can end up having are called endospores now endospores are metabolically inactive structures this is where the bacteria becomes dormant like it's sleeping okay these are dehydrated cells and they have a thickened layer of peptidoglycan to protect them against like hostile or unfavorable conditions now these cells can't reproduce because their metabolism is so low but it does allow them to survive while those harsh conditions are present these are very hardy guys and they can actually survive in the environment and on surfaces for many years okay because they are going to have this dormant structure however when the environment is better for them it can trigger them to become where they start germinating and when they germinate they return to the vegetative state and they can do metabolism and they can reproduce okay so this causes them to be an issue because they can sit dormant for several years and then potentially make you sick right so that's how endospores are an issue and they are an increased virulence factor in order to help make sure infections don't occur with organisms that have endospores we must kill them during a sterilization process we got to make sure that the sterilization can actually penetrate and get through that endospore structure so some examples with endospores we have here gram-positive endospore producing bacilli this is like clostridium clostridium causes botulism tetanus and gas gangrene lots of things you do not want okay botulism is going to actually release a toxin that causes your muscles to relax okay we actually use this for botox okay they use the toxin from clostridium to do botox the issue is if you have the bacteria it keeps making the toxin and it's not so much of an issue until it gets to your diaphragm and then you can't breathe because it can't contract on the other hand tetanus causes it releases a toxin that causes your muscles to contract violently it causes you to have all kinds of major cramps and those can actually be so severe they can break bones and gas gain green guys it's terrible it eats away at the tissue producing a toxic gas that smells terrible but also pulls away the layers of tissue causing more damage we also see some bacillus species will have these endospores some cause food poisoning and then anthrax is also a part of this and you've probably heard a little bit about anthrax or at least in the past where it was mailed to like the pentagon and things like that and it caused severe illnesses that's why in some places they treat the male to try to eradicate any endospores that could be transported so implications guys the big thing here is proper food preservation like canning needs to be done properly because if you don't and these endospores are in there they can survive for a long time and also the importance of vaccines and public awareness it's important to make people aware of what's going on and that whole idea of using proper techniques with preservation of food and vaccine now eukaryotes guys we are going to focus more of that on another presentation that we'll do over chapter 12 but remember that we're going to be looking at protista and focusing mostly on the protozoa with a few algae fungi we're going to look at yeast and molds and with animalia we're going to look at the helmets the parasitic worms remember that some of these will also have flagella flagella cilia and cell walls similar to what we talked about in this presentation but all of them do contain a membrane-bound nucleus and organelles because they are in the eukaryotic group they're eukaryotes