Behavior Genetics
Study of the relative power and limits of genetic and environmental influences on behavior.
Environment
In behavior genetics, this refers to every non genetic, or external, influence on our traits and behaviors.
Chromosomes
Threadlike structures made of DNA molecules that contain the genes. In conception, the 23 in the egg are paired with the 23 in the sperm.
DNA
A complex molecule containing the genetic information that makes up chromosomes.
Genes
The biochemical units of heredity that make up the chromosomes; they are segments of DNA molecules capable of synthesizing a protein.
Genome
The complete genetic instructions for making up an organism.
Identical Twins
Develop from a single (monozygotic) fertilized egg that splits in two and therefore are genetically identical.
Fraternal Twins
Develop from two separate (dizygotic) eggs fertilized by different sperm and are therefore no more genetically similar than ordinary siblings.
Temperament
refers to a person's characteristic emotional reactivity and intensity.
Molecular Genetics
The subfield of biology that studies the molecular structure and function of specific genes.
Heritability
Refers to the proportion of variation among individuals that can be attributed to genes.
Interaction
Occurs when the effects of one factor (such as environment) depend on another factor (such as heredity)
Epigenetics
The study of influences on gene expression that occur without a change in DNA.
Evolutionary Psychology
The study of the evolution of behavior and the ind using principles of natural selection.
Natural Selection
The evolutionary principle that traits that lead to increased reproduction and survival are the most likely to be passed on to succeeding generations.