Myers EXPLORING PSYCHOLOGY (6th Edition in Modules) Module 5 The Nature of Behavior James A. McCubbin, PhD Clemson University Worth Publishers

Genes: Our Biological Blueprint  Chromosomes  threadlike structures made of DNA that contain the genes  DNA (deoxyribonucleic acid)  complex molecule containing the genetic information that makes up the chromosomes  has two strands-forming a “double helix”- held together by bonds between pairs of nucleotides

Genes: Our Biological Blueprint  Genes  biochemical units of heredity that make up the chromosomes  a segment of DNA capable of synthesizing a protein  Genome  the complete instructions for making an organism  consisting of all the genetic material in its chromosomes

Genes: Their Location and Composition NucleusChromosomeGene CellDNA

Evolutionary Psychology  Natural Selection  the principle that, among the range of inherited trait variations, those that lead to increase reproduction and survival will most likely be passed on to succeeding generations  Mutations  random errors in gene replication that lead to a change in the sequence of nucleotides  the source of all genetic diversity

Evolutionary Psychology  Evolutionary Psychology  the study of the evolution of behavior and the mind, using the principles of natural selection  Gender  in psychology, the characteristics, whether biologically or socially influenced, by which people define male and female

Evolutionary Psychology  Men preferred attractive physical features suggesting youth and health  Women preferred resources and social status

Behavior Genetics  Behavior Genetics  study of the relative power and limits of genetic and environmental influences on behavior  Environment  every non-genetic influence, from prenatal nutrition to the people and things around us

Behavior Genetics  Identical Twins  develop from a single fertilized egg that splits in two, creating two genetically identical organisms  Fraternal Twins  develop from separate eggs  genetically no closer than brothers and sisters, but they share the fetal environment Identical twins Fraternal twins Same sex only Same or opposite sex

Behavior Genetics  Temperament  a person’s characteristic emotional reactivity and intensity  Interaction  the effect of one factor (such as environment) depends on another factor (such as heredity)