chap 2 Flashcards
what are directly observable characteristics that depend in part on the individuals genotypes?
phenotypes
what are the complex blend of genetic information that determines our species and influences all our unique characteristics?
genotypes
what are the rodlike structures in the nucleus of a cell that store and transmit genetic information?
chromosomes
what chemical substance are chromosomes made up of?
deoxyribonucleic acid
how identical is the dna of humans and chimpanzees?
95%
what looks like a twisted ladder and is composed of segments called genes?
DNA
what are segments of DNA?
genes
what sends the instructions for making a rich assortment of proteins?
protein-coding genes
what triggers chemical reactions throughout the body and are the biological foundations on which characteristics are built?
protein-coding genes
what two special cells combine to make new individuals?
gametes or sex cells
what determines the gender of the baby?
sperm
how are gametes formed?
meiosis
what process halves the number of chromosomes in cells?
meiosis
what is a cell that results when a sperm and ovum unite at conception?
zygote
true or false: sex cells are unique in that they contain only 23 chromosomes
true
identical or fraternal: frequency of this type of multiple birth is 1/350 births
identical
identical or fraternal: most common type of multiple birth
fraternal
identical or fraternal: genetically no more alike than ordinary siblings
fraternal
identical or fraternal: type of multiple birth created when a zygote duplicates and separates into two clusters of cells
identical
identical or fraternal: older maternal age, fertility drugs, and in vitro are associated with this type of multiple birth
fraternal
true or false: children of single births are often healthier and develop more rapidly than twins in the early years
true
what is each form of a gene called?
allele
what is the child if alleles from both parents are alike?
homozygous
what is the child of alleles from both parents are different?
heterozygous
will child display trait if homozygous?
yes
will child display trait if heterozygous?
depends on relationship between alleles
what commonly known recessive disorder affects the way the body breaks down proteins contained in many foods?
PKU (phenylketonuria)
how do doctors identify PKU?
blood test
what is the most common intervention to prevent harmful aspects of PKU?
diet! eliminate phenylalanine from diet
can changes in environment alter the extent that an inherited disorder influences a person’s well-being?
yes
how does PKU manifest?
baby’s mental health declines, retardation
why are serious diseases only rarely due to dominant alleles?
a child with a dominant allele will develop disease and probably die before they can reproduce
why is huntington’s disease a dominant disorder that has endured?
it is a type of dementia and the symptom onset isn’t until mid to late 30s, when they’ve already reproduced
true or false: males are more likely than females to be affected by X-linked inheritance
true, their sex chromosomes do not match
what are 2 types of x-linked disorders?
hemophilia (blood doesn’t clot)
fragile x-syndrome (intellectual disability)
how are harmful genes created?
mutation! sudden, permanent change in a dna segment
what characteristics are due to polygenic inheritance?
height, weight, intelligence, personality
what inheritance involves many genes determining the characteristic?
polygenic
most chromosomal defects result from mistakes occurring during meiosis
chromosomal abnormalities
what is the most common chromosomal abnormality, where there is a defect in 21st chromosome?
down syndrome
the risk of bearing a down syndrome baby rises with:
maternal age (exponentially in 40s)
what are consequences of down syndrome?
intellectual disability, speech problems, limited vocabulary, slow motor development, short and stocky, flat face, protruding tongue, almond eyes, and crease in hand (50% of time)
what are factors that promote development in down syndrome babies?
engage with surroundings, physical therapy, occupational therapy, speech therapy, sign language
what reproductive tech involves taking a sperm and injecting it at the top of the cervix?
artificial insemination
how much is artificial insemination?
$1500/each time
what is the success rate for AI?
70-80%
what is in vitro?
sperm and egg added to petri dish, form zygotes and injected at top of cervix
how much is in vitro?
$10-15k
what is the success rate of in vitro?
50% and decreases with age
what are risks involved with surrogate motherhood
1) everyone wants baby
2) nobody wants baby
3) favors wealthy, exploits poor
4) increases insecurities in surrogate’s children
what are 3 reasons that adopted children have more learning and emotional difficulties than other children?
1) the bio mom is unable to care for child, passes on tendencies like alcoholism/depression, or stress, poor diet, inadequate medical care
2) pre-adoptive history of conflict-ridden family relations, lack of affection, neglect, abuse, deprivation
3) adoptive parents and children are less alike than bio children which creates family disharmony
why is the search for birth parents more likely during adolescence/early adulthood?
marriage and childbirth trigger it
true or false: international adoptees develop more favourably than birth siblings or institutionalize agemates who remain in their birth country
true
what does the term “bidirectional influences” mean within a family?
we mutually influence one another
what is the difference between direct and indirect influences?
direct = person-person contact
indirect = 3rd party influences (quality of marriage affects interactions with kids)
what is coparenting?
mutually support each other’s parenting behaviours - united front
what are 3 interrelated variables that define socioeconomic status (SES)?
1) income
2) years of education
3) prestige of/skill required - career
how does SES affect the timing and duration of phases of the family life cycle?
low SES - marry earlier, have kids earlier, more kids
high SES - marry later, kids later, less kids
what is the influence of SES on parenting practices and parent-child interaction?
low SES - more criticism & physical punishment
focus on external characteristics - obedience, cleanliness, polite
high SES - talk to & read to
focus on psychological characteristics - curiosity, motivation, happiness
true or false: affluent parents often engage in high levels of family interaction and parenting that promote favourable development
false
why are affluent youth more troubled or poorly adjusted?
parents value accomplishments more than character - like things that are objectively measurable
affluent parents are busy, they get nannies, aren’t present
what simple routine is associated with a reduction in adjustment difficulties for both affluent and low-SES youths?
family dinners
what two groups are hit hardest by poverty?
1) parents under 25 with young kids
2) elderly who live alone
what percentage of single moms with preschool kids live @ or below poverty line?
50%
what are 5 outcomes children of poverty are more likely to have than other children?
1) poor physical health
2) persistent cognitive deficits
3) high-school dropout
4) mental illness
5) antisocial behavior
why do neighborhood resources have a greater impact on economically disadvantaged kids than well-to-do?
affluent families don’t want/need those resources
students whose parents are involved in school activities and attend parent-teacher conferences show…
increased academic achievement
what reduces the energy that low SES parents have for school involvement?
daily stressors
how do low SES parents often feel about coming to school?
uncomfortable
who should be responsible for rearing young children?
any individual who has contact with them
in what type of societies do individuals define themselves as part of a group?
collectivist
in what societies do people think of themselves as separate entities and concern themselves with their own needs?
individualist
which type of society values an interdependent self?
collectivist
which type of society values an independent self?
individualist
what are 3 values of a collectivist society?
1) social harmony
2) collaborative endeavours
3) responsibility to others
what are 3 values of an individualist society?
1) personal choice
2) achievement
3) individual exploration
what characteristics of the african & latino-american extended family reduce the stress of poverty and single parenthood?
live in extended family households, numerous adults contributing $, numerous adults contributing to childcare
why have attempts to help children through public policy been difficult to realize in the US?
we value privacy and self-reliance, and programs are expensive
true or false: the minimum income guaranteed to americans age 65 and older is less than the poverty line
true
what is heritability?
measures extent that individual differences in complex traits in specific population are due to genetic factors
what studies compare characteristics of family members and provide heritability estimates?
kinship studies
true or false: among children and adolescents, heritability estimates from intelligence and personality are approximately 0.50, indicating that genetic makeup can explain half the variance in these traits
true
true or false: unlike intelligence, heritability of personality does not increase over the lifespan
true
what are 3 limits of heritability?
1) environments of twin pairs are less diverse than gen pop, so HE are exaggerated
2) misapplied (between ethnic groups)
3) limited usefulness - no precise info
what is gene-environment interaction?
because of genetic makeup, individuals differ in responsiveness to qualities of environment
true or false: sometimes different genetic-environmental combos can make two people look the same
true
what is gene-environmental correlation?
our genes influence the environments to which we are exposed
what are the 3 types of gene-environment correlation?
passive, evocative, active
what type of gene-environment correlation involves children increasingly seeking out environments that fit their genetic tendencies (niche-picking)
active
what type of gene-environment correlation involves a child’s style of responding influences others’ responses, which then strengthen the child’s original style
evocative
what type of gene-environmental correlation involves parents providing an environment consistent with their own heredity. the child has little control
passive
what is development resulting from ongoing, bidirectional exchanges between heredity and all levels of environment?
epigenesis
can environmental modification of a gene expression occur at any age, even prenatally?
yes
what is methylation?
biochemical process triggered by certain experiences. set of chemical compounds (methyl group) lands on top of gene and reduces or silences its expression
what factors during pregnancy concerning methylation can produce unfavourable outcomes?
maternal smoking, harmful prenatal environment, severe maternal stress
