exam 1 Flashcards
genetic variation
vary between organisms
mutation
2 sources of genetic variation
dna
made of 3 nucleotides
recombination
crossing over in meiosis
haploid
1n
diploid
2n
gamete
sex cell
germline mutation
in sex cells, can be passed
somatic mutation
in cell that is not producing, so the mutation cant be passed
3 variations
deleterious, neutral, adventageous
deleterious variation
hurts
neutral variation
doesnt help or hurt
advantageous variation
helps it in the environment, may increase in frequency in the population
adaptation
genetic change in individual makes it better able to survive and reproduce
allele frequency
of alleles / total # of alleles at lous
homozygous recessive
pp
homozygous dominant
PP
zygote
offspring
genotype
pp PP Pp
phenotype
“purple white”
how to measure variation
with allele frequency to measure how rare
test cross
electrophoresis
take fluid put in gel matrix in electric field
enzymes
catalysis. proteins. molecules that allow chemical reactions to proceed (geneticists look at enzymes through electrophoresis)
hardy weinberg equilibrium
5 conditions for hardy weinberg equilibrium
- no selection
- no migration or immigration
- no mutation
- large population
- random mating
- no selection
no difference in survival/ reproductive success of individuals
- no migration or immigration
new people could change the makeup
- no mutation
…
- large population
significantly large. no sampling errors
- random mating
…
genetic drift
change in allele frequency due to random effects of population size
allele frequencies equation
p + q = 1
genotype frequencies equation
p2 + 2pq + q2 = 1
autosomal
not sex linked
natural selection
driving mechanism for how populations change, frequency of beneficial alleles increase
darwins postulates
- all organisms show variation
- all species produce more offspring than can survive
- individuals w favorable traits will tend to survive and reproduce, passing the favorable traits onto offspring
- the result is a change toward favorable traits in the population
- over time this leads to populations becoming adapted to their environment
artificial selection
breeders breed traits they want
modern synthesis
30s and 40s mendell and darwin
patterns of selection
complex traits
stabilizing selection
selects against extremes
directional selection
selects against one of the two extremes
disruptive selection
selects against the mean
sexual selection
promotes an individual’s access to mating. showy aspects threat to safety
other evolutionary forces
can change allele frequency.
selection = ?
selection = evolution
migration
gene flow, movement of allele population from one to another
mutation
change in allele frequency, how we get a new variation
genetic drift
random change in allele frequency due to effect of small population size
genetic bottleneck
allele frequency altered due to population crash
founders effect
large population with small groups that breaks off and starts a new population
divergence
molecular evolution
molecular clock
using amount of change between 2 groups to estimate time together (conserved vs unconserved genes)
species
fundamental biological unit
BSC
biological species concept
ring species
two populations form ring. one place they can interbreed, they cant at the other
ecological species concept
splitting things up based off ecology
competitive exclusion
2 species cannot fill same niche at same time
ecological niche
end dimensional hypervolume
gregory gause
1930s single cell protists
evolutionary species concept
how these different groups have evolved, common ancestor
cladogram
branching tree that shows where populations diverge. bigger level than species
reproductive isolation
prezygotic, post zygotic
prezygotic
heaving apart before zygote, stopping geneflow prefertilization
postzygotic
stopping geneflow after fertilization
zygotic
zygote, combo of 2 gametes
(prez iso) behavioral
dances, songs, things to attract
prezygotic isolation
behavioral, biochemical, anatomical, temporal, spacial
postzygotic isolation
genetic incompatibility
(prez iso) biochemical
not the right chemical, nothing happens
(prez iso) anatomical
“lock and key” if it doesn’t fit it doesn’t happen
(prez iso) temporal
different times where it occurs
(prez iso) spacial
not in same space
(post z iso) genetic incompatibility
issue w chromosomes (mule)
allopatric speciation
different places split species
vicariance
geographical barrier keeping apart (snapping shrimp)
dispersal
colonization of distant area
peripatric speciation
nearby place dispersal few individuals from big forming island population (big shifts short time)
stabilizing selection
!
peripatric
!
adaptive radiation
!
cospeciation
2 completely diff evolving same time same way in response to each other
sympatric speciation
disruptive selection
allopatric
speciation w no gene flow between diverging populations
sympatric
sub pops w diff characteristics
instantaneous speciation
happens right away (hybrid can reproduce w hybrid)
polyploidy
like haploid but more
speciation
split into 2 species
prokaryotic
no membrane bound organelles. no nucleus
eukaryotic
membrane bound organelles. yes nucleus
Domain Kingdom Phylum Class Order Family Genus Species
dear king phillip came over from great spain
things in prokaryotes
plasma membrane, nucleoid region, cytoplasm, ribosomes
can have: cell wall, flagella
nucleoid region
circular chromosomes, plasmids
prokaryote
domain bacteria and domain archaea
eukaryote
domain eukarya
cell
smallest unit of life
scientific name
Genus + species
semi-autonomous
organelles that can kinda work alone
mitochondria
powerhouse turns adp to atp
chloroplasts
photosynthesis
eukaryotic cells
cytoplasm, nucleus, cytoskeleton, nuclear membrane, endoplasmic reticulum, golgi apparatus, vacuoles, plasma membrane
endosymbiont theory
inside cells, there’s a symbiotic relationship
symbiosis
mutualism, parasitism, commensalism
mutualism
both benefit (clownfish, anenome)
parasitism
one benefits, one harms
commensalism
one isn’t helped or hurt. no effect
multicellular organisms
!! tissue
tissue
collection of cells that work together to perform a specific function
kingdom Protista
single cell
simple multicellularity
poor or minimal communication, no resource sharing. NO TISSUES
diffusion
!
complex multicellularity
true tissue
