Unit 1.1 & 1.4

Mutation

A random error in gene replication that leads to change

Identical twins

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

Behavior genetics

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

Interaction

The interplay that occurs when the effect of one factor (such as environment) depends on another factor (such as heredity)

Enviornment

Every nongenetic influence, from prenatal nutrition to our experiences of the people and things around us

Natural Selection

The 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

Genome

The complete instructions for making an organism

Epigenetics

The study of the molecular mechanisms by which environments can influence genetic expression

Nature-nuture issue

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

Evolutionary Psychology

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

Heredity

The genetic transfer of characteristics from parents to offspring

Fraternal twins

Individuals who developed from separate fertilized eggs. They are genetically no closer than ordinary siblings, but they shared a prenatal environment

Genes

The biochemical units of heredity

Corpus Callosum

The large band of neural fibers connecting two brain hemispheres and carrying messages between them

Split Brain

A condition resulting from surgery that separates the brain's two hemispheres by cutting the fibers connecting them

Neurogenesis

The formation of new neurons