At the Beginning of the Twentieth Century, Geneticists

question 22

Multiple Choice

At the beginning of the twentieth century, geneticists

• A) thought that inheritance was fundamentally discontinuous.
• B) argued that Mendelian genetics supported Darwin's idea that adaptation occurs through the accumulation of small variations.
• C) agreed that evolution proceeded by the gradual accumulation of small changes.
• D) believed that genes had no discernible effect on phenotypes.

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Definitions:

Fixed-Interval

In the context of operant conditioning, a schedule of reinforcement where rewards are given at fixed times, provided the correct response is made.

Smelled Food

The act of detecting the aroma of food, which can trigger physiological reactions such as salivation and influence appetite.

Operant Behavior

Behavior emitted spontaneously or voluntarily that operates on the environment to change it.

Respondent Behavior

Reactions that are automatic and involuntary, typically elicited by specific stimuli, contrasted with operant behavior, which is influenced by its consequences.