In Your Textbook, the Lower Frequency of Sickle-Cell Anemia Among

question 24

Multiple Choice

In your textbook, the lower frequency of sickle-cell anemia among present-day Americans of West African ancestry as compared to people living in West Africa is attributed to

• A) genetic drift.
• B) gene flow.
• C) new mutations.
• D) natural selection.

---

Definitions:

Little Albert

An early 20th-century experiment by John B. Watson and Rosalie Rayner, demonstrating classical conditioning in a young child.

White Rat

Commonly used in psychological experiments, particularly in the study of behavior, learning, and conditioning; often associated with B.F. Skinner's work.

Conditioned Stimulus

A previously neutral stimulus that, after association with an unconditioned stimulus, elicits a conditioned response.

White Rat

Commonly used in psychologic and medical research, a laboratory rat of a breed that is white in color.