In Fred Griffith's Experiments, Harmless R Strain Pneumococcus Became Lethal

question 13

Multiple Choice

In Fred Griffith's experiments, harmless R strain pneumococcus became lethal S strain pneumococcus as the result of which of the following?
1) horizontal gene transfer
2) transduction
3) conjugation
4) transformation
5) genetic recombination

• A) 2 only
• B) 4 only
• C) 2 and 5
• D) 1, 3, and 5
• E) 1, 4, and 5

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Definitions:

Placebo

A harmless substance with no therapeutic effect, used in controlled experiments to test the efficacy of treatments.

Control Group

In experimental research, a group of subjects who do not receive the treatment being tested, used as a benchmark to measure the effect of the treatment.

Dependent Variable

In an experiment, it is the variable being tested and measured, which is expected to change due to manipulation of the independent variable.

Independent Variable

A variable in an experiment that is manipulated by the researcher to observe its effect on the dependent variable.