Myers’ PSYCHOLOGY (6th Ed) Chapter 3 The Nature and Nurture Of Behavior James A. McCubbin, PhD Clemson University Worth Publishers

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

Genes: Our Biological Blueprint zGenes ybiochemical units of heredity that make up the chromosomes ya segment of DNA capable of synthesizing a protein zGenome ythe complete instructions for making an organism yconsisting of all the genetic material in its chromosomes

Genetics and Behavior NucleusChromosomeGene CellDNA

Evolutionary Psychology zNatural Selection ythe principle that, among the range of inherited trait variations, those contributing to survival will most likely be passed on to succeeding generations zMutations yrandom errors in gene replication that lead to a change in the sequence of nucleotides ythe source of all genetic diversity

Evolutionary Psychology zEvolutionary Psychology ythe study of the evolution of behavior using the principles of natural selection zGender yin psychology, the characteristics, where biologically or socially influenced, by which people define male and female

Evolutionary Psychology zMen everywhere preferred attractive physical features suggesting youth and health

Behavior Genetics zBehavior Genetics ystudy of the power and limits of genetic and environmental influences on behavior zEnvironment yevery nongenetic influence, from prenatal nutrition to the people and things around us

Behavior Genetics zIdentical Twins ydevelop from a single zygote (fertilized egg) that splits in two, creating two genetic replicas zFraternal Twins ydevelop from separate zygotes ygenetically 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 zTemperament ya person’s characteristic emotional reactivity and intensity zHeritability ythe proportion of variation among individuals that we can attribute to genes ymay vary, depending on the range of populations and environments studied

Behavior Genetics zInteraction ythe effect of one factor (such as environment) depends on another factor (such as heredity) zMolecular Genetics ythe subfield of biology that studies the molecular structure and function of genes

Environmental Influence zTwo placental arrangements in identical twins

Environmental Influence zExperience affects brain development Impoverished environment Rat brain cell Rat brain cell Enriched environment

Environmental Influence zA trained brain

Environmental Influence zCulture ythe enduring behaviors, ideas, attitudes, and traditions shared by a large group of people and transmitted from one generation to the next zNorm yan understood rule for accepted and expected behavior

Environmental Influence zPersonal Space ythe buffer zone we like to maintain around our bodies zMemes yself-replicating ideas, fashions, and innovation passed from person to person

The Nature and Nurture of Gender zX Chromosome ythe sex chromosome found in both men and women yfemales have two; males have one yan X chromosome from each parent produces a female zY Chromosome ythe sex chromosome found only in men ywhen paired with an X chromosome from the mother, it produces a male child

The Nature and Nurture of Gender zTestosterone ythe most important of the male sex hormones yboth males and females have it yadditional testosterone in males stimulates xgrowth of male sex organs in the fetus xdevelopment of male sex characteristics during puberty zRole ya set of expectations (norms) about a social position ydefining how those in the position ought to behave

The Nature and Nurture of Gender zGender Role ya set of expected behaviors for males and females zGender Identity yone’s sense of being male or female zGender-typing ythe acquisition of a traditional masculine or feminine role

The Nature and Nurture of Gender zSocial Learning Theory ytheory that we learn social behavior by observing and imitating and by being rewarded or punished zGender Schema Theory ytheory that children learn from their cultures a concept of what it means to be male and female and that they adjust their behavior accordingly

The Nature and Nurture of Gender zPercentage agreeing “The activities of married women are best confined to home and family” Men Women 1967 ‘71 ‘75 ‘79 ‘83 ‘87 ‘91 ‘95 Year Percentage