Chapter 2 Flashcards
phenotypes
directly observable characteristics
genotype
complex blend of genetic information
chromosomes
store and transmit genetic information
23 pairs in humans
DNA
deoxyribonucleic acid
chemical that codes template for proteins, breakthrough when they discovered the double helix shape
gene
segment of DNA, determines characteristics
protein-coding gene
directly affect our body’s characteristics
regulatory genes
modify instructions given by protein-coding genes
about 95% of _________ and human DNA is identical
chimpanzee
gametes
sex cells (eggs and sperm), only contain 23 chromosomes
meiosis
form gametes, goes through reduction division
zygote
combination of sperm and ovum at conception
in meiosis, men end up with ___ sperm and women end up with ____ ovum
4; 1
autosomes
non-sex chromosomes (22 out of 23 pairs)
most common type of multiple offspring
dizygotic/fraternal twins (shoutout)
maternal factors related to fraternal twins
ethnicity (best odds for black people)
family history of twins
age (35-39)
nutrition
more likely with each birth
fertility drugs and IVF
allele
each form of a gene
homozygous
presence of the same two alleles
heterozygous
2 different alleles are present
dominant-recessive inheritance
only one allele affects the child’s inheritance, and it is the dominant one
carriers
people who only have one recessive allele, making them unaffected by the trait but can pass onto offspring
Cooley’s anemia (description, dom or rec, auto or x)
Pale appearance, impacted physical growth, slow behavior development in infancy
recessive; autosomal
Cystic Fibrosis (description, dom or rec, auto or x)
lungs, liver and pancreas secrete mucus leading to difficulty with breathing
recessive; autosomal
PKU (description, dom or rec, auto or x)
inability to metabolize an amino acid (phenylalanine) causing CNS damage
found in kids/prenatally
recessive; autosomal
Sickle Cell Anemia (description, dom or rec, auto or x)
abnormal sickling of RBCs causing oxygen deprivation, pain, swelling and tissue damage (painful and damaging)
recessive; autosomal
Tay-Sachs disease (description, dom or rec, auto or x)
CNS degradation –> blindness, deafness, and poor muscle tone
starts showing brain damage @ toddler, no cure/treatment, high frequency in jewish populations
recessive; autosomal
Huntington’s disease (description, dom or rec, auto or x)
CNS degradation –> muscle coordination difficulties (don’t appear until 35 or later), fatal
dominant; autosomal
Marfan syndrome (description, dom or rec, auto or x)
tall, slender build w/ heart defects and eye abnormalities
dominant; autosomal
Duchenne muscular dystrophy (description, dom or rec, auto or x)
degenerative muscle disease, lose ability to walk in 7-13 yrs of age
recessive; x-linked
hemophilia (description, dom or rec, auto or x)
blood fails to clot normally
recessive; x-linked
diabetes insipidus (description, dom or rec, auto or x)
excessive thirst and urination
recessive; x-linked
incomplete dominance
pattern of inheritance where both alleles are expressed in phenotype creating an intermediate between the two ends
carriers of what disease are most resistant to malaria?
sickle cell anemia
genomic imprinting
alleles are imprinted to make it so that one pair member (mother or father) is activated
often temporary, may be erased in following generation
fragile x syndrome
abnormal DNA repetition on X chromosome cause cognitive impairments, attention deficits, high anxiety and signs of autism
mutation
sudden but permanent change in a segment of DNA
polygenetic inheritance
many genes affect the characteristic in question
genes on chromosome ___ are linked to Down Syndrome
21
genetic counseling
communication process designed to help couples access their chances of having an offspring with a hereditary disorder
socioeconomic status (SES)
combines three variables:
1) years of education
2) prestige of one’s job
3) income
high-SES families emphasize _____ while low-SES emphasize ____
self-direction and happiness; obedience and politeness
2 main factors that are causing homelessness
insufficient availability of low-cost housing
release of people with mental illness from institutions w/o necessary supports
collectivism vs. individualism
c: people stress group goals over individual ones
i: people are concerned with their own personal needs and value independence
what country is more individualistic compared to most?
USA
the US ranks usually _____ when compared to other nations on indicators of children’s health and wellbeing
last :(
heritability estimates
measure the extent to which individual differences in complex traits in a specific population are due to genetic factors
usually exaggerate the role of heredity
kinship studies
compare characteristics of family members
gene-environment interaction
due to genetic makeup, people differ in their responsiveness to qualities of the environment
gene-environment correlation
our genes influence the environments to which we are exposed to
niche-picking
tendency to actively choose environments that complement our hereditary
epigenesis
development resulting from ongoing, bidirectional exchanges between heredity and all levels of environment
genes affect behavior and experiences while behavior and experiences affect gene expression
methylation
biochemical process triggered by certain experiences that lands on a gene and changes its impact
mitosis
replication of cells to grow or heal
dominant vs. recessive
dom: expressed in Bb or BB genotypes
rec: expressed in bb genotype
range of reaction
genes set boundaries within we operate
canalized
some traits are more canalized than others (more malleable by the environment), the stronger = less influenced
ex) strongly canalized: eye colors
neurofibromatosis (description, dom or rec, auto or x)
tumors all over the body, all benign
dominant; autosomal
color blindness (dom or rec, auto or x)
recessive; x-linked
severe combined immune deficiency (description, dom or rec, auto or x)
no immunity to anything, can quickly succumb to illnesses that other people with immune systems can fight off
recessive; x-linked
imprinting (genetic)
one gene is silenced, sometimes only maternal or paternal is expressed (important for fetus development)
practice genetics!!
yupppppp
mothers that were exposed to the Rwandan Tutsi genocide had what effects
increased PTSD
impaired regulation of stress hormones
elevated methylation of the GR gene
parents with PTSD often have children with PTSD
