Which of the Following Is True About Photosynthetic Bacteria

question 1

Multiple Choice

Which of the following is true about photosynthetic bacteria?

• A) They are the most primitive of all bacteria.
• B) Photosynthesis appears to have evolved several separate times.
• C) Photosynthetic bacteria all appear to be closely related.
• D) A comparison of rRNA genes in different lineages of photosynthetic bacteria would reveal that the genes are almost identical in all lineages.
• E) All photosynthetic bacteria appear to have evolved relatively recently.

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Definitions:

Positively Punished

The addition of an unpleasant stimulus in response to a behavior, resulting in a decrease in the likelihood of that behavior being repeated.

Negatively Punished

A term in behavioral psychology referring to the decrease in the frequency of a behavior due to the removal of a pleasant stimulus following the behavior.

Positive Reinforcer

A stimulus which, when presented after a behavior, increases the likelihood that the behavior will occur again.

Negative Reinforcer

A stimulus whose removal following a behavior increases the likelihood that the behavior will occur again in the future.