Download Module 3 Nature vs. Nurture

How do families, friends and culture
affect the way we live?
- Study the
relative effects
of genes and
environment
on behavior
- The nature vs.
nurture debate
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Genes – biochemical units of heredity that
make up a chromosome
Chromosome – Threadlike structures made of
DNA molecules that contain genes (46 total, 23
from each parent)
DNA (deoxyribonucleic acid) – complex
molecule that contains genetic information that
makes up chromosomes
Cell -> Nucleus -> Chromosomes -> DNA ->
Genes
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Genes made up of
nucleotides (A,T,C, or G)
Genome – complete
instructions for making an
organism consisting of all
genetic material in its
chromosomes
Humans have about 30,000
different genes
Does anyone know the
animal humans are most
genetically related to?
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Genes are responsible for predisposing our
appearance and behavior, not concretely
determining either.
Predisposition – a situation that allows
something else to occur but doesn’t necessarily
cause it to occur; “Her genetic makeup left her
with a predisposition to develop Alzheimer's.”
Mutations – random error in gene replication
that lead to a change in genetic code
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Natural selection – the
idea that , among the
inherited trait
variations, those
contributing to survival
will most likely be
passed on to future
generations
Adaptation – species
changing genetically to
better survive in their
environment
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What traits do you believe are essential
for human survival?
Do you think that those people who
reproduce in large numbers in our
society today should really be the ones
reproducing at such rates? Why or why
not?
What correlation does economic status
have with reproduction rates worldwide
if any?
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Identical twins – twins that develop from a
single fertilized egg and then split in half; are
genetically identical
Fraternal twins – twins that develop from
separate eggs; no more related genetically than
normal siblings
Twin studies have discovered that identical
twins are strikingly similar is intelligence,
attitude and even brain waves!
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Studies of adopted
children show that they
exhibit similar
personality traits of
their biological parents
However, adopted
children tend to be
smarter, more
productive and more
successful than their
biological parents
Nurture is back in the
game!
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Are parents to blame
for success/failure of
children? Studies say
“not really”.
Siblings raised
together tend to be as
different personalitywise as two random
people on the street.
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For our brains to reach
their developmental
potential, early
experience is
CRITICAL.
Children raised in
abusive homes tend to
be less intelligent that
children raised in
loving environments.
Score one for nurture!
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Peers hold a heavy influence on the behaviors
of individuals (i.e. smoking, drinking,
promiscuity )
Bandwagon phenomenon
“Fitting In”
Parents influence behaviors of children by
supplying them the environment from which
they have to work within (i.e. parents “choose”
which neighborhood to live in)
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Culture – shared attitudes and beliefs of a
group passed on from one generation to the
next.
Norms – understood rules for accepted and
expected behavior; prescribe “proper” behavior
Individualism – giving priority to one’s goal
over the goals of the group
Collectivism – giving priority to the group’s
goal over the goal of the individual
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Scientists have done studies on sexuality to
discover if it is determined by genetics or
environment. Using what you know now
about genetics and environment, draw your
own conclusion about human sexuality:
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Do you think people are born with a predisposition to
be either straight or gay?
To what extent does peer influence have on
sexuality?
How do cultural norms affect sexual behavior?