Which of the Following Is the Best Evidence for a Three-

question 37

Multiple Choice

Which of the following is the best evidence for a three- domain system?

• A) There are three distinctly different Gram reactions.
• B) Some bacteria live in extreme environments.
• C) There are three distinctly different cell structures.
• D) There are three distinctly different cellular chemical compositions.
• E) None of the above.

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Definitions:

Variable-Interval

A schedule of reinforcement where a response is rewarded after an unpredictable amount of time has passed, in the context of behavioral psychology.

Operant Responding

Operant responding involves a type of learning where behavior is modified by its consequences, through reinforcement or punishment, initially described by B.F. Skinner.

Unpredictable

not able to be predicted or foreseen, often because of constant changes or lacking a pattern.

Variable-Interval

A timetable for reinforcement where the time intervals between receiving reinforcement vary around a certain average but are unpredictable.