Reviewing the Environmental Factors of Microbial Growth

in this video, we're going to begin reviewing the environmental factors of microbial growth. And so in this video, once again, we're only going to review information that we've already covered in our previous lesson videos. And so if you're already feeling good, then feel free to skip this video if you'd like. However, if you need a little bit of extra help, then stick around because this video could be very helpful for you. And so here in this example problem it wants us to fill in the following blanks throughout the flow chart that's down below, that's reviewing all of those environmental factors of microbial growth that created these different classes. And so over here on the far left, what we have is the classification of microbes by growth temperature. And notice that there are these five groups that are classifying these microbes based on their growth temperature. And so the first group that we have over here are the psy crow files and the psych profiles are going to be organisms that love the cold. Because psy crow is a route that means cold and file is a route that means loving. And so these are going to grow between negative five degrees Celsius to degrees Celsius and extremely cold environments. Then what we have are the psy crow troughs. And the psycho troughs are also has that route. Psy crow. So they're going to also grow in cold environments. But troughs as a as a route that means nutrients. And so these are going to grow in a cool environment, such as your refrigerator, for example, Which is gonna have temperatures between zero and 35°C. Uh then what we have next are the Meso files and the miso files grow on me and you as well, because they grow in temperatures between 10 and degrees Celsius. And human body temperatures right around 35 ish degrees Celsius, approximately. Then what we have. Next are the thermo files And the Thermo files are going to grow in hotter temperatures between 40 and 80°C And last but not least what we have are the hyper thermo files, which are going to grow and even hotter environments than the Thermo files. They grow between 65 and 115°C. Next, what we have are the classification of microbes based on their oxygen requirements. And so recall that for the electron transport chain, a lot of microbes require oxygen as the final electronic sector and those that require oxygen are called Arabs, whereas those that do not require oxygen are are referred to as anna robes. And so down below what we have are these other classifications of microbes by their oxygen requirement. We've got these five groups here. So the first one that we have are the obligate Arabs and obligate Arabs are going to be obligated to aerobic conditions, so they require oxygen in order to grow and they will not grow in any other regions that do not have oxygen. Then what we have next are the faculty native anna robes and the faculty of anna robes can grow in the presence or the absence of oxygen. However, they grow better in the presence of oxygen and that's simply because oxygen allows for more energy, more ATP to be generated and that allows for better and more growth. However, faculty of an Arabs, they will grow in both the presence and absence of oxygen, but they grow better in the presence of oxygen. Then next week we have are the micro arrow files and micro is a route that means small. So these require a small amount of oxygen in order to survive too much. Oxygen is toxic and no oxygen is also going to not be good for it. So it needs a small amount of oxygen. Next what we have are the obligate and erodes. And the obligate anaerobic are practically the opposite of the obligate. Arabs. Because the obligate anaerobic cannot grow with oxygen, they can only grow an anaerobic environments. They are obligated to anaerobic environments that lack oxygen. Then last but not least what we have are the arrow tolerant anna robes and these can grow equally and with or without oxygen. And so oxygen is not toxic to these organisms and they really will grow equally with or without oxygen. Then what we have over here are the classification of microbes by the ph requirement. And so we have three groups here we have the Asado Files And the set of files are going to have an optimum ph of less than 5.5. So they have an acidic optimum p Next what we have are the new Trow files, which as their name implies, they are going to have an optimum ph near neutral between 5.5 and about 7.9 here, close to neutral. And then the last group that we have here are the alcohol. Oh, fouls. And the alcohol files are going to have uh ph that is about or basic or alkaline ph is above uh equal to greater than or equal to eight. So they have basic phs or alkali phs optimum ph d s. Uh Then last, but not least what we have over here are the classification of microbes by salt tolerance. And we've got these four different groups here. First we have the non halo tolerant organisms which do not tolerate salt concentrations. They really don't tolerate sodium chloride concentrations. So they must grow in areas that do not have uh salt or do not have a lot of salt concentration at all. Then what we have are the halo tolerant organisms. The halo tolerant organisms, as their name implies, are capable of tolerating medium or moderate concentrations of salt, such as your skin, for example, Then we have the Halo files. And once again, files means as a route that means loving. So these grow in high concentrations of salt between one and 14% sodium fluoride concentration and then last but not least what we have are the extreme halo files which are going to be growing in salt concentrations that are greater than 15% sodium chloride here. So they grow and even saltier environments than the halo files. And so really this is just a recap in a review of all of the information that we talked about in our previous lesson videos. And so I'll see you all in our next video