Term
| Hardy-Weinberg Equilibrium can also be considered what? |
|
Definition
| no evolution, or genetic equilibrium |
|
|
Term
| during Hard-Weinberg equilibrium there is no change in? |
|
Definition
| allele frequencies between generations or genotype frequencies between generations |
|
|
Term
|
Definition
| disorder where humans are missing an enzyme that breaks down phenylalanine which can cause mental retardation if it accumulates in blood |
|
|
Term
| phenylketonuria is a ___________ disorder |
|
Definition
| recessive, only exhibited in the homozygous recessive condition |
|
|
Term
| can you use the H-W theorem to predict the frequency of humans carrying the recessive allele, but not showing the phenylketonuria (heterozygotes)? |
|
Definition
|
|
Term
|
Definition
|
|
Term
| q or p in the hardy-weinberg equation |
|
Definition
|
|
Term
| q^2 or p^2 in the h-w equation |
|
Definition
| freqeuncy of homozygotes for one allele |
|
|
Term
|
Definition
| the frequency of heteroygotes |
|
|
Term
| five conditions required for a population to be in Hardy-Weinberg equilibrium |
|
Definition
| no mutation, random mating, infinitely large population size, no differential reproductive success, no gene flow |
|
|
Term
| true or false, if there is no change in allele frequency the is no change in genotype frequency |
|
Definition
|
|
Term
|
Definition
| the frequency of alleles and genotypes between generations |
|
|
Term
| infinitely large population size can lead to... |
|
Definition
|
|
Term
| no differential reproductive success also means |
|
Definition
|
|
Term
|
Definition
| no immigration from another population with different allele frequencies |
|
|
Term
| what processes can cause evolution? |
|
Definition
| mutation, genetic drift, selection, gene flow |
|
|
Term
|
Definition
| creates new variation (only minor change in allele frequencies |
|
|
Term
|
Definition
| alters allele frequencies randomly |
|
|
Term
| selection (natural or sexual) |
|
Definition
|
|
Term
| gene flow (immigration or emigration) |
|
Definition
| changes allele frequencies in ways that can be non-adaptive |
|
|
Term
| genetic drift can lead to |
|
Definition
| a random loss of alleles -> loss of genetic diversity |
|
|
Term
| genetic drift can lead to |
|
Definition
| a random loss of alleles -> loss of genetic diversity |
|
|
Term
| genetic drift is most pronounced in |
|
Definition
|
|
Term
| genetic drift is due entirely |
|
Definition
|
|
Term
|
Definition
| changes in allele frequency within a population across generations |
|
|
Term
| a sampling error (genetic drift) in one generation can have a _________ effect |
|
Definition
|
|
Term
| two mechanisms of genetic drift |
|
Definition
| genetic "bottleneck" and founder event |
|
|
Term
| genetic (population) "bottleneck" |
|
Definition
| very large population dramatically reduced in size |
|
|
Term
| scientific name for the Northern Elephant Seal |
|
Definition
|
|
Term
| Bottleneck example of the Northern Elephant Seal |
|
Definition
| original population -> slaughtered for blubber -> 5--100 remained -> protected by government -> now about 200,000 but much less variation at the 24 electrophoretic loci (no genetic variation) |
|
|
Term
| scientific name for Southern Elephant Seal |
|
Definition
|
|
Term
| no bottleneck effect for Southern Elephant Seal |
|
Definition
| no decline in population ->24 electrophoretic loci have far more genetic variation |
|
|
Term
| stickleback example of founder effect |
|
Definition
| a few come from the ocean and move into a lake |
|
|
Term
|
Definition
| very small founder group drawn from a much larger population |
|
|
Term
| Ellis van Crevald Syndrome is an example of... |
|
Definition
|
|
Term
| symptoms of Ellis van Crevald Syndrome |
|
Definition
| disproportionate short stature, extra digits, abnormal knee joints, other stuff |
|
|
Term
| story of Ellis van Crevald Syndrome |
|
Definition
| recessive allele on chromosome 4, amish of E. pennsylvania, 200 settlers 18th century, Mr and/or Mrs. king were carriers |
|
|
Term
| founder effect of the amish disease... proportions |
|
Definition
| 0.001 in most human populations -> 0.0025 if only one of the King's carried the allele |
|
|
Term
| Amish inbreed and what happens to the proportion of allele for recessive disease? |
|
Definition
| increase from 0.0025 -> 0.07 |
|
|
Term
| founder effect from nature |
|
Definition
| Silvereye, songbird in Australia and Tasmania |
|
|
Term
| methods of silvereye experiment |
|
Definition
| captured individuals on each island, collected blood samples and released, evaluated diversity at 6 microsatellite loci |
|
|
Term
| how was the prediction of the Silvereye experiment supported? |
|
Definition
| no clear decrease each colonization, overall trend significant |
|
|
Term
| genetic drift occurs in _____________ |
|
Definition
|
|
Term
| in genetic drift what kinds of deviations are most likely? |
|
Definition
| same frequency as current allele frequency |
|
|
Term
| are extreme deviations in allele frequency likely due to genetic drift? |
|
Definition
| no, but they are possible. slight deviations are more likely, and the same frequency is theoretically most likely |
|
|
Term
| genetic drift effect is greatest in _________ populations |
|
Definition
|
|
Term
| why is genetic drift more effective in small populations? |
|
Definition
| because each "error" represents a larger fraction of the total number of alleles in the population |
|
|
Term
| in small populations genetic variation will be lost ___________ than in large populations |
|
Definition
|
|
Term
| graphs of genetic variation in different size populations |
|
Definition
| small population has biggest fluctuations and goes to fixation quicker. Big populations don't even go to fixation on these graphs and there are smaller fluctuations |
|
|
Term
| heterozygosity in different size populations |
|
Definition
| exponential decrease in small populations... much less decrease when the population size is greater |
|
|
Term
| as alleles drift towards fixation or loss... the frequency of heterozygotes... |
|
Definition
|
|
Term
| assuming random mating, the frequency of heterozygotes is... |
|
Definition
|
|
Term
| when is heterozygosity greatest? |
|
Definition
| at a locus with two alleles when one of the alleles is present at a frequency of 0.5 |
|
|
Term
| as one allele declines in frequency, overall heterozygosity... |
|
Definition
|
|
Term
| Buri et al is an example where... |
|
Definition
|
|
Term
| Buri et al example methods |
|
Definition
| 107 lab populations derived from 8 males and 8 females whom were heterozygotes for a mutation called brown. each generations 8m/8f selected at random. beginning parents phenotypically distinct from either homozygote (2 phenotypes) |
|
|
Term
|
Definition
| 19 generations, many fixed for one allele, equal frequency of loss for each allele, heterozygosity declines more rapidly than expected |
|
|
Term
| how fast did the heterozygosity decline for the population of 16 in the Buri et al.? |
|
Definition
| as if it were a population of 9 |
|
|
Term
| symbol for effect population size |
|
Definition
|
|
Term
| effective population size is very sensitive to what? |
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| effective population size when there is one male and 9 females |
|
Definition
| 4(1 times 9)/ 1+ 9 -> 36/10 -> 3.6 |
|
|
Term
| effective population size |
|
Definition
| size of an ideal theoretical population that would lose heterozygosity at the same rate as a real population of interest |
|
|
Term
| the effect population size is usually smaller than what? |
|
Definition
|
|
Term
| what could the smaller effective population size of Buri et al. be due to? |
|
Definition
| random death of some individuals, sexual selection |
|
|
Term
| what are two measures of genetic diversity? |
|
Definition
| polymorphism and allelic richness |
|
|
Term
|
Definition
| fraction of loci in the genome that have at least two alleles with frequencies above 0.01 |
|
|
Term
|
Definition
| average number of alleles per locus |
|
|
Term
|
Definition
| loss of alleles -> reduces overall genetic diversity |
|
|
Term
| genetic drift can result in inbreeding depression if the population is __________ |
|
Definition
|
|
Term
| populations will follow _________ evolutionary trajectories due to drift alone |
|
Definition
|
|
Term
| negative assortative mating |
|
Definition
| mating with unlike individuals |
|
|
Term
| positive assortative mating |
|
Definition
| mating with like individuals |
|
|
Term
| positive assortative mating with relatives |
|
Definition
|
|
Term
| what can inbreeding be due to? |
|
Definition
| mating among relatives, small population size |
|
|
Term
| inbreeding can result in... |
|
Definition
| a decrease in heterozygosity |
|
|
Term
| what can be used to detect inbreeding in nature> |
|
Definition
| Hardy-Weinberg Equilibrium |
|
|
Term
| example of bottleneck and inbreeding |
|
Definition
|
|
Term
| how are sea otters an example of inbreeding? |
|
Definition
Lidicker and McCollum examined 31 allozyme loci and the genotypes of 33 otters, 2 alleles at on of the loci and they didn't meet Hardy-
Weinberg equilibrium |
|
|
Term
| how did the one loci of the sea otters not meet H-W equilibrium? |
|
Definition
| more homozygotes and fewer heterozygotes than expected if mating is random |
|
|
Term
| where the bottleneck was less severe for otters... |
|
Definition
| in Alaska (vs california), there are more heterozygotes |
|
|
Term
| does inbreeding directly change the allele frequencies in a population? |
|
Definition
|
|
Term
| can inbreeding influence population evolution? |
|
Definition
|
|
Term
| how does inbreeding effect the mean fitness of a population? |
|
Definition
| reduces the mean population fitness, due to exposure of deleterious recessives |
|
|
Term
| what is an extremely bad case of decrease of heterozygotes? |
|
Definition
| loss of function mutations becoming homozygoous |
|
|
Term
| loss of function mutants are usually hidden in what? |
|
Definition
|
|
Term
| inbreeding will expose what? |
|
Definition
| loss of function mutations |
|
|
Term
| in loss of function mutations one copy of a wild-type (functional) allele... |
|
Definition
| can produce enough gene product for normal development |
|
|
Term
| cousin matings typically result in... |
|
Definition
| greater mortality of babies |
|
|
Term
|
Definition
|
|
Term
|
Definition
| fitness of selfed individuals |
|
|
Term
|
Definition
| fitness of outcrossed individuals |
|
|
Term
| inbreeding depression is apparent in... |
|
Definition
|
|
Term
| two types of stressors on plants |
|
Definition
competition and herbivorous insect outbreak
|
|
|
Term
| what effects the survival of jewelweed during insect outbreaks? |
|
Definition
|
|
Term
| inbreeding effect is greater when in plants?.... |
|
Definition
|
|
Term
| what may compensate for genetic deficits early in life in plants? |
|
Definition
|
|
Term
| leveling of inbreeding is related to what in birds? |
|
Definition
| the number of eggs that fail to hatch. the more eggs that fail to hatch, the higher the inbreeding coefficient |
|
|
Term
| evidence of strong selection to avoid inbreeding |
|
Definition
| mate choice, genetically-controlled incompatibility, dispersal |
|
|
Term
| inbreeding is unavoidable is... |
|
Definition
| population is small enough |
|
|
Term
|
Definition
males display leks -> vulnerable
boom display using orange air sacs
vulnerable to hunting |
|
|
Term
| why has the population of the greater prairie chicken declined? |
|
Definition
| people hunting, less prairie... now hunting of them is banned |
|
|
Term
| what caused the continued decline of greater prairie chicken population? |
|
Definition
| accumulation of deleterious recessives = genetic load |
|
|
Term
| even though sanctuaries were added for the greater prairie chicken... |
|
Definition
| the population still continued to decline |
|
|
Term
| how did people help the greater prairie chicken when the population was still declining? |
|
Definition
| moved them to other locations and increased the genetic diversity... but is it really still the Illinois Greater Prairie Chicken? |
|
|
Term
| what was darwin's grand idea? |
|
Definition
|
|
Term
|
Definition
| differential reproductive success, higher mean reproductive success of one type relative to another |
|
|
Term
| what is natural selection due to? |
|
Definition
| the relationship between phenotype ad environment |
|
|
Term
| what does natural selection not require? |
|
Definition
| differences between the phenotypes (variants) |
|
|
Term
| what requires genetic difference between phenotypes? |
|
Definition
|
|
Term
| what is a good example of natural selection requiring different phenotypes, but not genetic differences? |
|
Definition
| Tonicella, the limpit that takes on the color of the algae it eats |
|
|
Term
| natural selection, unlike genetic drift produces.... |
|
Definition
|
|
Term
| natural selection favors... |
|
Definition
| one phenotype/ genotype/ allele over others in the population |
|
|
Term
|
Definition
| reproductive success of an individual or phenotype compared to others in the population |
|
|
Term
| fitness can also be thought of as |
|
Definition
| relative reproductive success |
|
|
Term
| what kind of individual would have a greater fitness or relative reproductive success? |
|
Definition
| one that produces more offspring than another in a population |
|
|
Term
| what kind of phenotype is said to have greater fitness or relative reproductive success? |
|
Definition
| a phenotype that produces on average more offspring than another in a population |
|
|
Term
| which observations led Darwin to come up with natural selection? |
|
Definition
| all organisms have the potential for very rapid increase in numbers, yet, natural population tend to be stable in size, variation exists in the traits of individuals in populations, some of variation is inherited |
|
|
Term
| deductions of Darwin on natural selection |
|
Definition
| many more offspring are produced than survive to reproduce, individuals that inherit characters that confer higher reproductive success will replace those characters that confer lower reproductive success |
|
|
Term
| what was Thomas Malthus concerned with? |
|
Definition
| the decline of living conditions in nineteenth century England |
|
|
Term
| what did Thomas M. blame the bad living conditions on? |
|
Definition
| too many babies, not enough resources to keep up, irresponsibility of lower classes |
|
|
Term
| does natural selection act only through competition for limited resources? |
|
Definition
| no, also predation, mate choice, etc. |
|
|
Term
| selection against deleterious recessive alleles (2 types) |
|
Definition
| complete (lethal selection) and partial selection against recessives |
|
|
Term
| complete (lethal) selection |
|
Definition
| 100% selection against the recessive, genetic death |
|
|
Term
| what is the reproductive success of homozygotes with a deleterious recessive allele? |
|
Definition
|
|
Term
| eliminating the homozygous recessive from the breeding pool changes what? |
|
Definition
| the residual mating frequencies |
|
|
Term
| progressive decline in the recessive, in the absence of mutation, would lead to what |
|
Definition
| loss of the recessive allele selected against, but it would take a LONG time |
|
|
Term
| lose of recessive is associated with what? |
|
Definition
| a decline in heterozygosity |
|
|
Term
| Dawson et al is an example of... |
|
Definition
| complete selection against a deleterious allele |
|
|
Term
| what happens in Dawson et al? |
|
Definition
| two populations established beginning with all heterozygotes and both populations have the recessive decline and the wild-type leads to fixation |
|
|
Term
| speed of decline of recessive in a population is determined by... |
|
Definition
| the extent of detrimental effect -> strength of selection |
|
|
Term
|
Definition
| reproductive capacity half that of wild-type |
|
|
Term
|
Definition
| reproductive capacity of homozygous recessive is 50-100% of wild-type |
|
|
Term
| least selection -> most selection |
|
Definition
| semisterile, subvital, lethal |
|
|
Term
| selection against deleterious recessive favors |
|
Definition
|
|
Term
| two types of selection against deleterious dominant alleles |
|
Definition
| lethal selection, partial selection |
|
|
Term
| lethal selection against a dominant defect |
|
Definition
| all new occurrences of defect are new mutations and have 0 fitness |
|
|
Term
| partial selection against a dominant defect |
|
Definition
| lower rates of removal, some deleterious alleles persist into next generation |
|
|
Term
| example of a partial selection against a dominant defect |
|
Definition
|
|
Term
| why is Achondroplasia nearly lethal? |
|
Definition
|
|
Term
| why does Achondroplasia persist? |
|
Definition
| the dominant allele is at a mutational hotspot and the mutations occur more as fathers age |
|
|
Term
| why will the rise of a new beneficial dominant be immediate? |
|
Definition
| none will be selected against |
|
|
Term
| rise of a new, beneficial allele will be slow at first because... |
|
Definition
| it isn't shown in the heterozygote so the heterozygote fitness won't be better |
|
|
Term
| could a new beneficial recessive allele be lost before it is revealed in a homozygous condition? |
|
Definition
| yes, because it is not revealed in heterozygotes |
|
|
Term
| ADH alleles in Drosophila |
|
Definition
| fruit flies make enzyme that breaks down ethanol. one of the alleles for this moves fast through electrophoretic gel |
|
|
Term
| Carver and Clegg experiment methods |
|
Definition
| raise two lines of flies on food with ethanol and two lines of flies on food without ethanol |
|
|
Term
| the flies that were raised on food with ethanol... |
|
Definition
| went towards fixation of the allele that codes for the enzyme that breaks down ethanol |
|
|
Term
| what were the controls in the flies (ethanol enzyme experiment) |
|
Definition
| the flies not fed food with ethanol |
|
|
Term
|
Definition
|
|
Term
| what does CCR5- triangle 32 allele code for? |
|
Definition
| a cell surface protein used by HIV to enter white blood cells |
|
|
Term
| what are humans that are homozygous for the CCR5-triangle 32 allele resistant to? |
|
Definition
|
|
Term
| how are heterozygotes for CCR5 -triangle 32 resistant to HIV |
|
Definition
| show slightly more resistance than a homozygote without the allele... 2-3 year delay in progression to AIDS |
|
|
Term
| 0.2 initial frequency of HIV resistant allele and high infection rate |
|
Definition
| the frequency of the allele increases, homozygotes with allele have highest fitness |
|
|
Term
| 0.2 initial frequency of HIV resistant allele and low infection rate |
|
Definition
| all genotypes have similar fitness, frequency of allele stays the same |
|
|
Term
| 0 freqeuncy of HIV resistant allele, high infection |
|
Definition
| no change in allele frequency... because it wasn't there. even though people with the allele would have a higher fitness |
|
|
Term
| the equilibrium frequency of a deleterious allele depends upon |
|
Definition
| strength of selection and mutation rate |
|
|
Term
| why is mutation selection balance only interesting when we are talking about a deleterious mutation? |
|
Definition
| because if the mutation is beneficial, it increases in frequency, and mutation acts in the same direction |
|
|
Term
|
Definition
| heterozygote has greater fitness than either homozygote |
|
|
Term
| which alleles will be retained in heterozygote superiority? |
|
Definition
| both alleles will be retained in the population because of the heterozygote advantage |
|
|
Term
| example of heterozygote superiority |
|
Definition
|
|
Term
| fly example of heterozygote superiority |
|
Definition
| stable equilibrium at 0.79, seen in two lines |
|
|
Term
| example of heterozygote inferiority |
|
Definition
| compound chromosomes of flies |
|
|
Term
| five types of selection of quantitative traits |
|
Definition
| directional selection, stabilizing selection, disruptive selection, fluctuating selection, frequency-dependent selection |
|
|
Term
| directional selection graph |
|
Definition
| normal distribution, mean shifted |
|
|
Term
| stabilizing selection graph |
|
Definition
| normal distribution gets skinnier |
|
|
Term
|
Definition
| either allele can become more common- depends only upon which becomes more common (by chance) than the equilibrium expectation |
|
|
Term
|
Definition
| normal distribution, mean selected against -> two peaks |
|
|
Term
|
Definition
| selection against individuals at one end of the phenotype distribution in favor of individuals at the other extreme |
|
|
Term
| example of directional selection |
|
Definition
|
|
Term
| how are rabbits in australia an example of directional selection? |
|
Definition
| inoculated with Myxomatosis virus and 95% died. rabbits more resistant to virus survive |
|
|
Term
| coevolution in rabbits in australia |
|
Definition
| virus that is less virulent infect rabbits that are more resistant. this is the only way they can continue to live (virus and rabbits). so the virus and rabbits that work well together survive |
|
|
Term
| being isolated facilitates... |
|
Definition
| diversification from other isolated areas, from same ancestor |
|
|
Term
| example of finches directional selection |
|
Definition
| birds that can eat bigger seeds favored in dry season -> next generation has bigger beaks |
|
|
Term
| candidate locus in finches for beak size |
|
Definition
| BMP4: signaling molecule that helps shape beaks of other bird specis, one QTL contributing to beak size |
|
|
Term
| when does directional selection occur? |
|
Definition
| environmental changes, new beneficial mutation appears |
|
|
Term
| what happens if directional selection persists? |
|
Definition
| genetic variation will be depleted, ultimately limiting response to selection |
|
|
Term
|
Definition
| selection against both extremes of the phenotype distribution |
|
|
