In a Sequence of DNA Taken from Various Species of Snails

question 88

Multiple Choice

In a sequence of DNA taken from various species of snails, researchers have found that the rates of nonsynonymous substitutions and synonymous substitutions are roughly the same. What can we infer from this pattern?

• A) Transversions are more common than transitions.
• B) Most of the amino-acid changes are neutral.
• C) Strong stabilizing selection is acting on this gene.
• D) Strong selection for change is acting on this gene.
• E) None of the above

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Definitions:

Schachter and Singer

Psychologists known for their Two-Factor Theory of Emotion, proposing that emotion is based on physiological arousal and cognitive labeling of that arousal.

Two-factor Theory of Emotion

A psychological theory suggesting that an emotion is determined by a cognitive appraisal of a physiological arousal and the environmental context in which it occurs.

Arousing Injection

A hypothetical or experimental procedure aiming to increase physiological or emotional arousal through the administration of substances.

Confederate

A supposed participant in a research study who actually is working with the experimenters, unknown to the real participants.