Unit 1.1 - Interaction of Heredity and Environment

AP Psychology vocabulary from collegeboard.

Nature (Heredity)

Refers to our genetic makeup — the DNA passed down from our parents

Evolutionary Perspective

The idea that behaviors have evolved over time because they helped our ancestors survive and reproduce

Natural Selection

Traits that enhance survival get passed on

Behavior Genetics

The study of how much our genes and environment affect our behavior

Mutations

Random changes to DNA that can lead to new traits

Genes

The basic unit of heredity

Genome

The complete set of genetic instructions for an organism

Nurture (Environment)

Everything from our family and friends to our culture and experiences

Twin Studies

Comparing identical (Monozygotic) twins with fraternal (Dizygotic) twins to see how much behavior is genetic vs environmental

Adoption Studies

Examining if adopted children are more like their biological or adoptive parents

Family Studies

Analyzing shared traits among relatives

Identical twins (Monozygotic)

Share 100% of their genes

Fraternal Twins (Dizygotic)

Share about 50% of their genes, just like other siblings

Epigenetics

How our environment can influence gene expression without changing the DNA itself

Eugenics

The controversial idea of improving human populations by selective breeding and controlling reproduction

Problem with Eugenics: Racial and Class Bias

The movement targeted marginalized groups, including immigrants, minorities, people with disabilities, and the poor. It falsely labeled these groups as “genetically inferior”

Problem with Eugenics: Forced Sterilizations

Over 60,000 people in the US were forcibly sterilized under eugenics laws. Many were sterilized without consent, often in institutions like prisons or mental hospitals

Problem with Eugenics: Violation of Human Rights

The movement ignored individual rights, treating people as tools for “breeding better humans” instead of as individuals with autonomy