Why are some organisms that constitute the normal microbiota described as commensals, whereas others are described as mutualistic?

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Accepted Answer

Hello, everyone and welcome. Our next question says Staphylococcus epidermitis is part of the normal microbiota found on human skin. It co exists harmlessly with its host under normal circumstances. Hence, they can be referred to as a mutualistic microorganisms. B comsal microorganisms, C parasitic microorganisms or D none of the above. So we have a situation where we have two organisms, the S epidermidis bacteria and humans in a relationship. And what characterizes this relationship, no harm or benefit to the human, but there's a benefit to the bacteria and that the dead skin cells provide nutrients. So a relationship where the t in the relationship, one member benefits and the other is neither harmed nor benefits is a commences relationship. So the S epidermidis are choice B comsal microorganisms. So one benefits the other is neither harmed nor benefits from the relationship. When we look at our other answer choices, obviously, we can rule out choice. D none of the above. Since we have a correct answer choice, a mutualistic micro organisms describes a scenario where both participants in the relationship benefit from it. But since humans don't benefit particularly from the presence of S Emadi, then choice A is not the right description. And then choice c parasitic microorganisms describe a scenario where one participant benefits but the other is harmed by the association. Now, one thing to note is that our question specifically says it coexists harmlessly with its host under normal circumstances. There do exist situations when the staphylococcus epidermidis enters the body during surgery when it has a chance to when that skin barrier is breached with the insertion of an IV, placing of artificial um valves or joints. And then at the same time, there's a surgical opening when this bacteria enters inside the body. So outside of his normal environment that can cause harmful infections. But since under normal circumstances, it is harmless, you still would call that comsal and not choice c parasitic. So the staphylococcus epidermidis can be referred to as choice. B commence microorganisms. Hope to see you in the next video.

Why are some organisms that constitute the normal microbiota described as commensals, whereas others are described as mutualistic?

Verified Solution

Key Concepts

Normal Microbiota

Commensalism

Mutualism