Study Guide, Exam 2
(covering Chapters 4-6)
Nature and nurture
What is nature; what is nurture?
Nature: genetics, biological makeup, influence of hormones, hereditary. Nurture: everything that
isn’t biological. Social environment, family life, values/morals, experiences, people, events,
What do behavior geneticists study?
Relative power and limits of genetic and environmental influences on behavior
What are genes; how many in the human body? How do we know this?
Genes: biochemical units of hereditary that make up chromosomes. About 30,000 genes in
human body found from human genome project.
How much genetic material do human beings share with each other?
Humans are 99.95% genetically identical
How do genes determine traits? (hint: two characteristics of genes we talked about)
Gene expression. Active or inactive. Genes may be similar but pattern of expression produces
What is the difference between identical and fraternal twins?
Identical twins- produced form single egg split into two. Fraternal twins- develop from separate
What are the two categories of twin studies? You should understand how they allow researchers
to control for the effects of nature vs. nurture
Categories- twin and adoption. Identical twins together, fraternal twins together. Identical twins
together, identical twins apart.
What was the overall conclusion of the Minnesota twins study (Bouchard, 2004)?
Most, if not all of our psychological traits are inherited
What is heritability? What did the Twin study find with regard to heritability of personality? Of
mental ability/intelligence? Of psychological illness? 2
Heritability- extent to which variation between people can be attributed to genes. Study found
that personality is 40-50% heritable. Schizophrenia is 80% and anxiety/depression is 20-40%
Describe four critiques of the Minnesota twin study
People looking for similarities can find them, some twins spent much time together before the
study, some shares same physical appearance which has implications regarding how people
respond (ex attractiveness), adoption agencies placement of babies (required to place in similar
What do adoption studies show with respect to nature and nurture influences on personality? On
attitudes and values?
Nature heavily influences personality and nurture has less of an impact. Nurture has a big
influence on attitudes and values.
What are two key periods in the womb when hormonal influences are acting on males and
females (what are the hormones doing during these periods?)
At 7 weeks: genes activate or 23 pair of chromosomes. Male determines sex. Hormone
production begins. Stimulate growth of sex organs.
At 4 /5 month: hormones are released and act on brain which may explain development
differences in adulthood.
What is gender? What are gender roles? Are they driven more by nature or nurture? How do we
Gender: biological and social characteristics by which people define male and female.
Gender roles: society’s expectation about the way men and women should behave. Driven by
nurture because gender roles have changed over time.
According to evolutionary psychologists, how do mate selection strategies differ for men vs.
For men: mate selection is about reproduction
For women: mate selection is about raising a healthy child
Be familiar with David Buss’s methods and findings of what women want, what men want
Men: youth, physical beauty (waist to hip ratio of .70), fidelity
Women: resources, social status, older men, love and commitment, size/strength
What did the experiment by Townsend & Levy (1990) show; Clark & Hatfield (1989)? 3
Townsend and Levy: men attracted to attractive women, clothes didn’t mater. Women attracted
to higher social status/better outfit, looks didn’t matter.
Clark and Hatfield: men will be more likely to have sex with an attractive stranger. No women
What is conception? Define zygote, embryo, fetus
Conception: moment in time when sperm fertilizes the egg
Zygote: fertilized egg. Survival rate is 50%
Embryo- about two week to 8 weeks
Fetus- 9 weeks to birth
What is a teratogen? Be familiar with an example and its effects
Teratogen: agents, such as chemicals and viruses, that can reach the embryo or fetus during
prenatal development and cause harm. Examples: HIV, smoking, heroin, fetal alcohol syndrome
What have studies found regarding newborns and young babies’ senses and preferences?
Newborns prefer human voices to other sounds, particularly the mothers. Prefer mothers face and
What is habituation?
A decrease in response to stimulation after repeated presentations. Slow habituation =
What do researchers argue about our neural connections when we are born? When does the most
neural development unfold?
Most of brain cell s you have are present at birth. Growth explosion in connection after birth.
What are the last areas of the brain to develop? When does this occur?
Adolescence: most growth in association areas (cortex)
What happens to the brain soon after puberty?
There is a pruning process. Connection not used much get weak or shut down 4
What do researchers argue about the sequence of motor development in babies? What do they
argue is responsible for differences in the timing of these skills?
Motor skill development is universal but timing is different. Possible reasoning is timing is a
reflection of temperament and personality.
What is infantile amnesia? What did the preschool study (Pillemer, 1995) show?
Infantile amnesia: can’t remember things from before age 3.5 years. The preschool study found
that children aged 5 remembered an event more clearly than 3 year olds remembers
What did Rovee-Collier do and find?
Showed that babies learned and remembered by tying string to baby’s ankle and to mobile.
Kicked leg to make mobile move. Remembered mobile and distinguished it from other things.
Why does infantile amnesia exist according to contemporary thought?
Brain is changing so much and memories get lost in development.
Jean Piaget – what peaked his interest in cognitive development?
Kids around same age tend to make same errors on intelligence test.
Piaget’s theory of cognitive development: Be familiar with the stages and the major milestone(s)
associated with each stage
Stage 1: Sensorimotor stage: from birth to 2 years. Object permanence: object continues to exist
even though it cannot be seen (6 mo