Chapter 2: Genetic and Environmental foundation Flashcards
What are gametes? autosomes (body cells)? How many chromosomes are contained in body cells (autosomes)? sex cells (gametes)?
gametes are sex cells, autosomes are pairs of chromosomes that are not sex cells. 22 autosomes, 23rd is the sex cell.
how does meiosis produce genetic variability in the population? and why is this important?
during meiosis parts of the chromosome cross over and then divides producing variability, this is important for adaptation –> evolution
how is the sex of a baby determined in prenatal development?
XX vs XY, but hormones in the environment of development can lead to a change of sex.
How are identical and fraternal twins produced? give different names for both types.
identical (monozygotic twins) - single zygote is divided into 2.
fraternal (dizygotic twins) - two separate zygotes.
What is dominant -recessive inheritance? give an example of a disorder associated with this type of inheritance.
occurs in heterozygous pairing, occurs when only one allele affects the child’s development.
Example: PKU (phenylketonuria)–> can’t convert phenylalanine to tyrosine.
what is incomplete dominance? give example.
pattern of inheritance in which both alleles are expressed in the phenotype, resulting in a combined trait, or one that is immediate between the two.
ex: sickle cell - two recessive alleles. makes round blood cells to moon shaped.
What is an x-linked disorder, why are males more likely than females to be natively affected by x linked disorder.
when a harmful allele is carried on the x chromosome. Harmful to males because their sex chromosomes do not match. females it can be suppressed by the other x chromosomes but boys only have 1 x.
regarding family influences, what is the difference between a direct and indirect effect on children. give examples.
direct - 2 person relationships. I directly social connection between a parent and child.
indirect - 3rd parties. Grandparent, provide support by assistance (financially, child-rearing advice, etc).
SES (social-economical status), low vs. high and emphasis on raising their children
SES (3) - years of education, prestige of ones job or sill it requires, income.
low SES - emphasize on external characteristics (obedience, politeness, neatness and cleanliness).
high SES - curiosity, happiness, self-direction, and cognitive/social maturity.
Which group of young people is most influenced by the availability of community resources: low-income children rom dangerous neighborhoods, or higher income children from safe neighborhoods?
Low SES
heritability estimates vs concordance rates in behavioral genetics research. Why is it inappropriate to use these values when taking about an individual’s development.
heritability estimate (continuous variables) - portion of variation in attribute that is due to shared genes; rated - 0 to 1 concordance rate (categorical variables) - percentage of case in which a particular attribute is present in both members of a twin pair; rated 0 to 100% these do not look into the environmental factors that infers individuality.
why is it inappropriate to use heritability estimates for IQ from one sample to make generalized statements about the genet bases of ethnic differences in intelligence?
heritabilities computed on mostly white twin samples do not tell us what causes test score differences between ethic groups. large economical and cultural differences are involved.
gene-environment correlation (passive, evocative, active; niche-picking). give examples.
genetic environmental correlation - our genes influence the environments to which we are exposed
passive - child has no control over their environment, so it’s up to the parent; athletic parents will give child more outdoor time.
evocative - the responses children evoke from others are influenced by the child’s heredity, and these responses strength the child’s original style. ex:active babies receive more attention.
active; niche-picking - tendency to actively choose environments that complement our heredity. choosing an environment that feels right at the time.
epigenesis? example using parent-infant interaction.
epigenesis - development resulting from ongoing, bidirectional exchange between heredity and all levels of environment.
smoking during pregnancy can lead to ADHD. But children with homozygous for chromosome-12 gene; predisposed to symptoms of ADHD did not show change unless smoking occurred in environment.
