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Learn the toughest concepts covered in Microbiology with step-by-step video tutorials and practice problems by world-class tutors.

10. Dynamics of Microbial Growth

Growth Factors


Growth Factors

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in this video, we're going to begin our lesson on growth factors. And so some microbes require growth factors from the environment that they cannot synthesize on their own. And so growth factors can be defined as biological substances that are going to promote cellular growth. And festen Aegis organisms are organisms that are going to have really complex nutritional requirements. In other words, prestigious organisms are organisms that require many growth factors. And so, if we take a look at our image down below, notice, over here, on the left hand side, these little yellow circles that you see represent growth factors that a cell would obtain from its environment. And so the growth factor is going to be able to bind to a specific growth factor receptor that is going to be found in the membrane of the particular cell. And so when the growth factor binds to the growth factor receptor, it's going to trigger a cascade of events inside of the cell that ultimately leads to the cellular response and that cellular response is going to be cell division, allowing the cell to divide and grow thus the name growth factors, leading to cellular growth. Now again, a festive gis organism is an organism that has complex nutritional requirements and requires many different growth factors. And so notice here, we're showing you a prestigious organism that's saying I need tons of these growth factors. And so uh really this year concludes our brief introduction to growth factors and we'll be able to get some practice applying these concepts moving forward. So I'll see you all in our next video.

Small organic molecules that must be provided to bacteria for them to grow are called:


Some microorganisms are difficult to culture because they require very specific growth factors to flourish. For example, Neisseria gonorrhoeae is difficult to culture because it requires blood, hemoglobin, many amino acids and many vitamins to grow. Neisseria gonorrhoeae, is an example of what type of organism?