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concept
Introduction to Avoiding Host Defense Mechanisms
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in this video, we're going to begin our introduction to how pathogens avoid host defense mechanisms. And so pathogens have evolved a wide variety of mechanisms that allow them to avoid the defense mechanisms of a host. And so down below what we have is a map of our lesson on uh these mechanisms of avoiding host defenses. And so what you'll notice is the title of our map here is just going to be avoiding host defenses and how pathogens can avoid host defenses and cause disease. And so notice that there are a wide variety of mechanisms that we're going to talk about in more detail as we move forward in our course. And because this image represents a map you can use it as a map to help guide you as we move forward. So we're gonna be covering the left most branches first. So we'll talk about how um pathogens can hide within host cells to avoid host defenses. We'll talk about how they can avoid Figo sites in many different ways, by preventing their encounter with a ghost sites, by avoiding optimization, by fabio sites, by using capsules and preventing optimization by using fc receptors. Again we'll talk more details about this as we move forward. Then we'll talk about surviving inside of to go sites to avoid the host offenses, avoiding the complement system and avoiding antibodies such as using I. G. A proteus is uh using anti genic variation or mimicking host cells. And so again this is just a map of our lesson moving forward and you can refer back to this lesson in order to help guide you and help you figure out where we are within the lesson. And so this here concludes our brief introduction, and I'll see you all in our next lesson video, where we'll get to talk more details about hiding within host cells, so I'll see you all in that video.
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Problem
All of the following are methods that pathogens use to avoid phagocytosis by immune cells except which of these answers?
A
The pathogens avoid being bound by C3b proteins that trigger opsonization.
B
The pathogens possess Fc receptors which bind and change the orientation of antibodies bound to them.
C
The pathogens create IgA proteases which break down IgA antibodies before they can bind the pathogen.
D
The pathogens create toxins which damage the phagocytic immune cells stopping phagocytosis.
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Problem
Certain pathogens, like Staphylococcus aureus, hide within host cells to avoid being phagocytosed by immune cells. What other advantageous reasons would a pathogen have for hiding within host cells?
A
Avoid being bound by antibodies.
B
Avoid being bound by opsonization proteins like C3b.
C
Avoid triggering the complement system.
D
The pathogen can lie dormant until an opportune time to cause disease.
E
All of the above.