Lesson 1: Heredity & Environment

genes

biochemical units of heredity

environment

every non-genetic influence

fraternal twins

individuals who developed from separate fertilized eggs and shared a prenatal environment

fraternal twins are genetically no more similar than…

siblings

fraternal twins are also called…

dizygotic twins

interaction

interplay that occurs when the effect of one factor depends on another factor

evolutionary psychology

study of the evolution of behavior and the mind, using principles of natural selection

natural selection

principle that the inherited traits enabling an organism to survive and reproduce in a particular environment will, in competition with other trait variations, most likely be passed on to succeeding generations

heredity

genetic transfer of characteristics from parents to offspring

epigenetics

study of the molecular mechanisms by which environments can influence genetic expression without DNA change

identical twins

individuals who developed from a single fertilized egg that split in two, creating two genetically identical organisms

identical twins are also called…

monozygotic twins

behavior genetics

study of the relative power and limits of genetic and environmental influences on behavior

nature-nurture issue

longstanding controversy over the relative contributions that genes and experience make to the development of psychological traits and behaviors

human genome

complete cellular DNA instructions for human development and function

polygenic traits

traits influenced by several genes

mutation

random error in gene replication that leads to a change

family study

study that searches for traits and diseases that tend to be shared by family members

twin study

study that compares twins to measure the influence of genetics versus environment on specific traits or diseases

adoption study

study that investigates the relative influences of genetics and environment on human behavior and traits