Bio - Chapter 20 - genes within population (a)

natural selection

antibiotic resistance is an example of

the founder effect

the changes in allele frequencies that occur due to colonization of a new location by small group of individuals is called

false

true or false: mutation and gene flow are equally important in determining how allele frequencies change

genetic variation in a population

What did Hardy and Weinberg explain?

dissassortative mating

a type of nonrandom mating where phenotypically different individuals mate

intermediate

according to the theory of blending inheritance, offspring were expected to be phenotypically ______ relative to their parents, which confused scientists originally because variation would be diluted

allele frequencies

as a result of natural selection, the _____ , ______ of genes change over time

p + q = 1

for a gene with two alleles, what equation represents the sum of all allele frequencies

exhibit variations

in natural population, most genes

are likely to increase reproduction

natural selection favours characteristics that confer a survival advantage because these traits

adaption

natural selection results in ______ in a population

preventing binding to its target enzyme

resistance allele at a single gene in Norway rats diminishes the effectiveness of the pesticide, warfarin by

1. they are single based differences 2. more than 3 million have been noted in the human genome

select all the following that is true about SNPs

1.allele frequencies are changing between generation 2.genotype frequencies do not match those predicted by the hardy-weinsberg equation based on existing allele frequencies

select the observation that would indicate that a population is deviated from hardy-weinberg equilibrium

true

true or false: generic drift, mutations and nonrandom mating are three agents that can act to produce evolutionary changes in a population

false

true or false: natural selection is the same as evolution

1. so few individuals contribute to the next generation 2. small populations are sensitive to genetic drift 3. the gene pool of the surviving members of the population may be different from the original

3 reasons for population bottleneck

small

although random changes in allele frequencies can occur due to chance events when populations are of any size, the changes are most likely to be obvious when population size is

colouration

an adaption that allows the larvae of the butterfly to avoid predators is the______ of the caterpillar (pg 404)

0.64 AA, 0.32 Aa, 0.04 aa

consider a gene in a population of fruit bats. There are two alleles for this gene, A and a at 0.8 and 0.2. What is the genotype frequencies observed

0.84

consider a population with 100 cats. If 84 cats are black and 16 are white, what is the phenotypic frequency of black cats

location of the population

enzyme allele frequencies within a population may vary based on

genetic

evolution can result from any process that changes the ___ composition of a population

1. migration 2. natural selection 3. mutations

evolutionary change within a population can result from which of the following

1. reduce evolutionary change 2. remove alleles from the population 3. promote evolutionary change 4. introduce new alleles to a population

gene flow may

allele frequencies

genetic variation in a population results from evolutionary forces that cause _____ to change

unchanged

if a population is in Hardy- Weinberg equilibrium, allele and genotype frequency are _______ from one generation to the next

evolutionary

if a population is not in Hardy-Weinberg equilibrium then ________ processes are operating

evolution

if a population is not in hardy- weinberg equilibrium then ______ processes are operating

0.7

if the frequency of allele b in a population is equal to 0.7, then the frequency, with which a gamete will carry allele b is equal to_________ if the population is in Hardy-Weinberg equilibrium

0.18

in a population of painted turtles a dominate allele for a certain trait occurs at a frequency of 0.1. If this population is in Hardy-Weinberg equilibrium, what would be the expected heterozygotes

0.16

in a population of tree frogs the observed frequency of GG,Gg,gg genotype is 0.1,0.6,0.3. If the population was in Hardy-Weinberg equilibrium, what would the expected GG?

enzyme , geographic

mummichog fish have variable _______ allele frequencies according to their _________ location

genetics

natural population exhibits significant ______ and pheonotypic variation

selection for individuals resistant to pesticide as we increased pesticide use

pesticide resistance has rapidly evolved because

alternative alleles of genes encoding enzymes

protein electrophoresis gels can be used to distinguish which of the following

allele, alleles

the allele frequency is calculated by dividing the number of copies of a given ______ in a population by the total number of ________ in that population.

natural selection

the process in which beneficial traits that are heritable become more common in successive generations is called

natural selection

the theory of ________, __________ proposes that the variation among individuals is not created by experience, but is the result of pre-existing genetic differences

likely to be lost

what can likely happen to uncommon alleles in small,isolated populations as a result of genetic drift

1. the population of heterozygotes in the population decreases 2. the proportion of homozygotes increases

what can result from assortative mating

1. harmful alleles may increase in frequency 2. beneficial allele may increase 3. favourable alleles may be lost

what can result from genetic drift

genetic variation will decrease

what changes in genetic variation in a population are expected after a bottleneck then growth then return to original population size

genetic drift

what evolutionary mechanism results in random changes in allele frequencies from one generation to the next

the relative likelihood that a genotype will contribute to the gene pool of the next generation

what is fitness

the movement of allele into or out of a populaton

what is gene flow

random changes in the allele frequencies of a population over time

what is genetic drift

the study of the properties of genes in population

what is population genetics

mutation

what is the ultimate source of genetic variation (pg 401)

1. a moth that has gene for cryptic coloration 2. a plant with an enzyme that makes it disease-resistant

what reasons could cause evolutionary change by natural selection

1.Darwin thought that selection should always favour an optimal form 2.segregation of alleles among progeny of hybrids was not understood 3. genetic variant were expected to dilute if hybrid offspring were intermediate to adults

what was a reason that puzzled Darwin and others regarding genetic variation

assortative mating

which evolutionary mechanism changes genotype frequencies but does not change allele frequencies

directional selection

which type of selection acts to eliminate individuals at one extreme of a phenotypic range