Mendel Accounted for the Observation That Traits Which Had Disappeared

question 63

Multiple Choice

Mendel accounted for the observation that traits which had disappeared in the F₁ generation reappeared in the F₂ generation by proposing that

• A) new mutations were frequently generated in the F₂ progeny, "reinventing" traits that had been lost in the F₁.
• B) the mechanism controlling the appearance of traits was different between the F₁ and the F₂ plants.
• C) traits can be dominant or recessive, and the recessive traits were obscured by the dominant ones in the F₁.
• D) the traits were lost in the F₁ due to dominance of the parental traits.
• E) members of the F₁ generation had only one allele for each trait, but members of the F₂ had two alleles for each trait.

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Definitions:

Stimulus-Stimulus Learning

A type of learning where an association is formed between two stimuli, leading to a new learned response.

Two-Factor Theory

A psychological theory proposing that emotion is based on two factors: physiological arousal and cognitive label of the arousal, proposed by Stanley Schachter and Jerome E. Singer.

Negative Reinforcement

A behavioral principle where the removal of an unpleasant stimulus strengthens a behavior or increases its likelihood of being repeated.