Table 203 the Following Data Were Obtained from a Broth Dilution

question 4

Multiple Choice

Table 20.3 The following data were obtained from a broth dilution test:
$$\begin{array} { | c | l | } \hline \text { Concentration of Antibiotic X } &{ \text { Growth } } \\\hline 2.0 \mu \mathrm { g } / \mathrm { ml } & - \\\hline 1.0 \mu \mathrm { g } / \mathrm { ml } & - \\\hline 0.5 \mu \mathrm { g } / \mathrm { ml } & - \\\hline 0.25 \mu \mathrm { g } / \mathrm { ml } & + \\\hline 0.125 \mu \mathrm { g } / \mathrm { ml } & + \\\hline 0 & + \\\hline\end{array}$$ Bacteria from the 0.25 ?g/ml tube were transferred to new growth media containing antibiotic X with the following results:
$$\begin{array} { | c | l | } \hline \text { Concentration of Antibiotic X } & { \text { Growth } } \\\hline 2.0 \mu \mathrm { g } / \mathrm { ml } & - \\\hline 1.0 \mu \mathrm { g } / \mathrm { ml } & + \\\hline 0.5 \mu \mathrm { g } / \mathrm { ml } & + \\\hline 0.25 \mu \mathrm { g } / \mathrm { ml } & + \\\hline\end{array}$$ The data in Table 20.3 show that these bacteria

• A) were resistant to 1.0 ?g/ml at the start of the experiment.
• B) were killed by 0.5 ?g/ml of antibiotic X.
• C) are pathogenic.
• D) were killed by 0.125 ?g/ml of antibiotic X.
• E) developed resistance to antibiotics.

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Definitions:

Continuous Reinforcement

A learning process in which a behavior is reinforced each time it occurs, leading to rapid learning.

Behaviors Persist

Behaviors Persist refers to the phenomenon where actions continue or are repeated over time, often due to reinforcement or underlying psychological factors.

Intermittent Reinforcement

A conditioning schedule in which a behavior is rewarded or punished at irregular intervals, making the response more resistant to extinction.

Socialization

The process by which individuals learn and adopt the norms, values, and behaviors appropriate to their society or social group.