Bio Ch 20 & 21 Quiz

Front 1

hardy weinberg does what

Back 1

predicts an equilibrium of unchanging allel & genotype frequencies in a population

Front 2

mutation

Back 2

weak agent of change

Front 3

2 important consequences on allele frequency.

Back 3

enhances alleles by introducting new alleles into population & reduces the difference in allele frequewncy between two allele populations – become more homogenized over time

Front 4

non random mating

Back 4

assortative mating – does not change freq of ind alleles. Increases the proportion of homo indv. Disassortative mating phenotypically different ind mate. Produce excess of hetereo

Front 5

another type of non random mating

Back 5

inbreeding

Front 6

genetic drift

Back 6

statistical accidents random fluctuations in allele frequencies. Mostly affects frequency of nutral alleles. Usually leads to loss of alleles. Reduces genetic variation in population

Front 7

founder effect

Back 7

few ind found new population (small allelic pool)
amish community example (Ellis-van Creveld syndrome) dwarf too many fingers or toes.

Front 8

bottlebeck event

Back 8

drout, starvation, etc. kills population (drastic reduction in population) surviving alleles missing others from start

Front 9

natural selection

Back 9

environmental conditions determine which ind in a pop proeuce the most offspring

Front 10

3 conditions for natural selection to occur

Back 10

variation must exisrt among inds in a pop
variation among ind must result in differences in the number of offspring survival
variation must be geneticallyt inherited
artificial selection – dogs

Front 11

fitness

Back 11

a phenotype with greater finess usually increases in frequwncy
AA produces 5 offspring
Aa produces 4 offspring
Aa produces 1 offspring

Front 12

directional selection

Back 12

acts to eliminate one extremely from an array of phenotypes

Front 13

directional selection in guppies (example)

Back 13

More colorful guppies in areas where less predators

Front 14

disruptive selection

Back 14

Two or more extreme fenotypes are favored over lower fenotypes (acts to eliminate intermediate types) – snales separated by area for long times

Front 15

vector

Back 15

carrier of disease

Front 16

stabilizing selection or balancing selection

Back 16

(acts to eliminate both extrmes)
Favors survival of individuals with intermedia fenotype – increasing genetic diversity in population – population of birds are stabilization – birds with few eggs and many eggs less than in the middle
Balanced polymorphism is when 2 or more alleles are kepy in balance and are maintained a population over the course of many generations.

Front 17

frequency dependent selection

Back 17

depends on how frequently or infrequently a phenotype occurs in a population.
Negative freq dependent selection: rare phenotypes are favored by selection (cause fish eat the common one)
Positive freq dependent selection: common phenotypes are favored. Variation is eliminated from pop. Different phenotype stands out and is predated upon.

Front 18

oscilating selection

Back 18

selection favors one phenotype at one time and a different phenotype at another time. Birds on islands.. bigger beaks able to eat seeds during particular environmental conditions. Conditions change and reverse is seen.

Front 19

3 conditions for natural selection

Back 19

1. variation must exist in the population
2. this variation m,ust lead to differences among indv in reproductive success
3. Variation among ind must be genetically trnansmitted to the next generation

Front 20

Peter and Rosemary Grant studied med ground Finch on Galapagos isles. Daphne Major… for 30 years.

Back 20

Hypothesis: dry conditions produce larger seeds and mayu result in larger breaks succeeding generations odue to natural selection. Compared beak size of parents with offspring for many many years. Data shows natural selection from 1970-1990. Increase in birds with larger beak survived due to drout and only larger seeds found. Larger beaks were passed on to offspring propelling birds with larger birds thereafter

Front 21

peppered moth

Back 21

natural selection caused black colored moth’s to thrive during start of industrial revolution. – called industrial melanism

Front 22

when environmental conditions reverse

Back 22

, so does the selection pressures

Front 23

artificial selection

Back 23

breeder selects parents instead of nature

Front 24

fossils created by three events occured

Back 24

1. organism buried in sediment
2. calcium in bone and other hard tissue mineralize
gravel = conglomerate
sand = sandstone
mud = shale
3. surrounding sediment hardens into rock

Front 25

Paleontologists

Back 25

study fossils

Front 26

radioisotope dating

Back 26

tells how old the fossil is.
Measure amount of isotope and measure decay

Front 27

igneous rock

Back 27

is studied for dating. Lava rock that has cooled.
Fossil records document the course of life through time.

Front 28

Fossil of fishapod

Back 28

was intermediate species

Front 29

anatomical evidence for evolution

Back 29

Homologous structures are studied – leading to anatomical evidence for evolution. Ie. Bat wing vs. cat arm vs. human arm

Front 30

developmental homologies

Back 30

early stages of embryonic development, different species often look similar.

Front 31

vestical structures

Back 31

human ears have muscles but don’t use them like horses do. Evolutionary relics

Front 32

molecular homologies

Back 32

evidence for evolution in cells. All living species contain DNA. – similar biochemical pathways in all living organisms
Example. all species that use oxygen have similar proteins that make up ETC. nearly all living organisms can use glucose.

Front 33

molecular evidence in genome

Back 33

Dogs and wolves. Certain genes are fgound in diverse array of species, sequence of closely related organisms will tend to be more similar.

Front 34

biogeography

Back 34

the study of the georgragic distribution of species. Some plants and animals have similar appears but are inly distantly related.

Front 35

convergent evolution

Back 35

species are similar even though they evoled from different ancestors. Giant anteater’s tongue and snout is similar to Australian eckena. Also appears in plants.. open air root plants.