You Add an Unknown Phage to a Mixture of F⁺

question 124

Multiple Choice

You add an unknown phage to a mixture of F⁺ and F^- cells of

• A)The phage bound to a receptor on the sex pilus,and therefore only infected the F⁺ cells (leaving the F^- cells alone).
• B)The phage bound to a receptor on the F^- cells,leaving only them alive and allowing the F⁺ cells to die off.
• C)The phage integrated (lysogenized)the F^- cells,giving them a selective advantage over the F⁺ cells.
• D)F⁺ cells are uniquely susceptible to phage attack for unknown reasons.
• E)coli and plate out the bacteria.The bacterial colonies that grow are all F^-.How can you explain this phenomenon?

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Definitions:

Experimenter Bias

A form of bias introduced by the experimenter whose expectations about the outcome of the experiment can be subtly communicated to the participants.

Researchers Blind

A method used in studies where researchers are kept unaware of key aspects of the research, such as which participants belong to the control or experimental group, to prevent bias.

External Validity

The extent to which the results of a study can be generalized to other situations and to other people.

Random Error

Variability in data that arises from unpredictable fluctuations and inconsistencies in the measurement process.