Table 203
the Following Data Were Obtained from a Broth Dilution

question 19

Multiple Choice

Table 20.3
The following data were obtained from a broth dilution test:

$\begin{array}{ll}\text { Concentration of Antibiotic } X&\text { Growth }\\\hline2.0 \mu \mathrm{g} / \mathrm{ml} & - \\1.0 \mu \mathrm{g} / \mathrm{ml} & - \\0.5 \mu \mathrm{g} / \mathrm{ml} & - \\0.25 \mu \mathrm{g} / \mathrm{ml} & + \\0.125 \mu \mathrm{g} / \mathrm{ml} & + \\0 & +\end{array}$
Bacteria from the 0.25 µg/ml tube were transferred to new growth media containing antibiotic X with the following results:

$\begin{array}{ll} \underline{\text { Concentration of Antibiotic }} X& \underline{\text { Growth} }\\2.0 \mu \mathrm{g} / \mathrm{ml} \\1.0 \mu \mathrm{g} / \mathrm{ml} & - \\0.5 \mu \mathrm{g} / \mathrm{ml} & + \\0.25 \mu \mathrm{g} / \mathrm{ml} & + \\\end{array}$
-The data in Table 20.3 show that these bacteria

• A) Developed resistance to antibiotics.
• B) Can be subcultured.
• C) Were killed by 0.5 µg/ml of antibiotic X.
• D) Were killed by 0.125 µg/ml of antibiotic X.
• E) Were resistant to 1.0 µg/ml at the start of the experiment.

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Definitions:

Synchrony

The simultaneous occurrence, operation, or action of two or more things.

Timing

The selection of the precise or opportune moment to perform an action, which can greatly affect the outcome of an event.

Effortful Control

The ability to regulate one's responses, including emotional and attentional self-regulation, particularly through the exertion of willpower.

Exuberance

The quality of being full of energy, excitement, and cheerfulness; a joyful enthusiasm for life.