This lesson introduces how genetic differences can influence health and survival, and why a harmful genetic variant can remain common in a population. The example of sickle-cell anemia shows how a gene’s effects depend partly on the environment.
Sickle-cell anemia is a genetic condition in which red blood cells can become crescent-shaped rather than round. These cells may clog blood vessels and obstruct blood flow, causing severe pain, swelling, fever, and tissue damage.
All flashcards
Sickle-cell anemia
A genetic condition in which red blood cells can become crescent-shaped and obstruct blood flow.
Sickle-cell carrier
A person with one copy of the sickle-cell variant; carriers generally do not have full-blown sickle-cell anemia.
Natural selection
A process in which traits suited to an environment can become more common through differences in survival and reproduction.
Epigenetics
The study of changes in gene expression that do not require changes to the underlying DNA sequence.
Behavioral genetics
The study of how genetic and environmental influences contribute to differences among individuals.
Quiz questions
Why can carrying one copy of the sickle-cell variant provide an advantage in some regions?Answer: It can offer some protection against malaria's effects.
What question is most characteristic of evolutionary psychology?Answer: How broad behavior patterns may have evolved across generations.
How do twin studies commonly help researchers examine genetic and environmental influences?Answer: They compare trait similarity in identical and fraternal twins.
Why are broad racial categories limited as descriptions of genetic relationships?Answer: There is substantial genetic variation within racial categories.
Based on Psychology 2e by Rose M. Spielman, William J. Jenkins, Marilyn D. Lovett (OpenStax), licensed CC BY 4.0. Adapted into a summary, flashcards and quizzes.