In Two of Koch's Postulates (#2 and #3), a Pure

question 55

Multiple Choice

In two of Koch's postulates (#2 and #3) , a pure culture of the organism is required. Which of the following would NOT be a possible consequence of using a contaminated culture?

• A) You can't necessarily attribute the illness directly to the microbe in question-it may in fact be caused by the contaminating microbe.
• B) There's the possibility that the test animal might be acutely susceptible to the contaminating microbe, but completely resistant to the microbe you suspect causes the illness of interest. As such, when you introduce it into the test animal, it could confuse your final results.
• C) The problem is that one microbe may be toxic to the other. It may have killed all of your suspect microbe in the culture. Therefore, you can't be sure that you're infecting your test animals with the microbe you suspect is causing the illness, or if it's only the 2^nd (contaminating) microbe.
• D) Even though there's a contaminating microbe present, so long as the original suspect microbe is also present, the disease should still manifest in test animals. It should also still be recoverable from test animals following infection. As such, there's really no consequence to using a contaminated culture.

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Regions

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Free Frank

Free Frank McWorter was an African-American man who bought his freedom from slavery, and later established the town of New Philadelphia, Illinois.

New Philadelphia

A historically significant town in Illinois, founded by Free Frank McWorter, an African American man, in 1836; it is notable for being the first town platted and registered by an African American before the American Civil War.

Ex-Slave

A person who has been emancipated from slavery or has escaped from enslavement.