AP Psychology - 1.12

Heredity

 genetic transfer from parent to offspring; nature

Environment

non-genetic influences; nurture

Identical twins (monozygotic)

twins develop from a single egg that splits

Fraternal twins (dizygotic)

twins develop from separate fertilized eggs; genetically no closer than ordinary brothers/sisters…they just shared a prenatal environment

For what traits can we ask whether adopted children are morel like their biological parents (who contributed genes) or adoptive parents (who contributed a home environment)?

• For personality or any other given trait

  • Just because traits may be heritable, that doesn't necessarily mean that the traits will manifest themselves

Heritability

the extent to which variation within a group can be attributed to inherited genetic factors

• Ranges from 0 to 1; 0 indicates environment totally responsible for differences in the trait and 1 means that all variation in the trait can be accounted for genetically.

What does heritability only demonstrate?

Heritability only demonstrates the extent to which a trait is explainable by genetics, not the extent to which the trait will affect behavior in an individual outside of environmental influences

Epigenetics

the study of environmental influences on gene expression that occur without a DNA change

• Looks at what environmental factors turn genes on or off and how that info is passed to offspring

Evolutionary psychology

the study of the evolution of behavior and the mind, using principles of natural selection (traits that better help an organism survive & procreate will likely be passed to offspring)

What has given us the ability to learn and adapt to varied environments?

The gene combinations produced at conception, plus the mutations (random errors in gene replication that lead to change) that sometime result