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

question 29

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) Even though there's a contaminating microbe present, as long as the original suspect microbe is also present, the disease should still manifest in test animals and the organism should still be recoverable from test animals. As such, there's really no consequence to using a contaminated culture.
• D) 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 second (contaminating) microbe.
• E) These would all be consequences of using contaminated cultures.

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Definitions:

Role Schema

The cognitive structure that holds expectations and beliefs about the behaviors, attributes, and roles of individuals within certain contexts.

Group Schema

A shared cognitive framework held by members of a group, which helps them interpret and predict the behavior and attitudes of the group.

Internal

Pertaining to or existing within an entity (such as an individual, organization, or system).

Stable

Characterized by consistency, permanence, and resistance to change over time.