A Lab Technician Has Four Strains of Bacteria A) Minimal Media with Leucine and Streptomycin
B) Minimal Media

question 8

Multiple Choice

A lab technician has four strains of bacteria. Although he forgot to label them, he knows that they include one F+ strain, one Hfr strain, one F' strain, and one F- strain. He observed the following results after plating these strains on different media. Which of the following plates can be used to identify the F- strain? $$\begin{array} { | l l l l l l | } \hline \text { strain } & \text { his } & g \text { gu } & \text { cys } & \text { leu } & \text { str } \\\mathrm { F } ^ { + } & + & + & + & - & + \\\mathrm { Hfr } & + & + & + & + & - \\\mathrm { F } ^ { \prime } & + & + & + & + & - \\\mathrm { F } & - & - & - & + & + \\\hline\end{array}$$

• A) minimal media with leucine and streptomycin
• B) minimal media with histidine, glutamate, and cysteine
• C) minimal media with histidine, glutamate, cysteine, and streptomycin
• D) complete media
• E) minimal media with streptomycin

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Definitions:

Peer Interaction

The social engagement and exchanges between individuals of similar age or status.

Emotional Warmth

The feeling of empathy, compassion, and genuine care one person can show to another.

Norm of Reciprocity

A social norm dictating that people should respond to others with the same kind of behavior they have received.

Kin Selection

An evolutionary strategy that favors the reproductive success of an organism's relatives, even at a cost to the organism's own survival and reproduction.