chapter 25 quiz questions

Blue eyes are recessive to brown eyes in humans. If the frequency of blue-eyed individuals in a population is 16%, we can calculate that the frequency of the allele for blue eyes is: 16%. 32% 40% 48% None of the above.

40%

A Mendelian population is one that: is a group of interbreeding members of a species. evolves through changes in its gene pool. meets Hardy-Weinberg equilibrium conditions. A and B. All of the above.

A and B.

The Hardy-Weinberg equation can be extended to describe frequencies for: X-linked alleles. multiple alleles. multiple loci. A and B. All of the above.

A and B.

The Hardy-Weinberg equation implies: genotypic frequencies are determined by genotypic frequencies. populations that meet the equation are not evolving. a single generation of assortative mating will produce the predicted frequencies. A and B. All of the above.

A and B.

The effect of mutation on allele frequencies is usually small because: mutations are relatively rare. mutations can be backward or forward. mutations are usually selected against because they generally interfere with function. A and B. All of the above.

A and B.

As population genetics is studied, all of the following are of interest EXCEPT: genotype frequencies. allele frequencies. phenotype frequencies. mutation rates. Actually, all of these are of interest.

Actually, all of these are of interest.

The Hardy-Weinberg equation is described by all of the following EXCEPT: it requires that there be only two alleles. it applies to traits determined by only a single locus. it predicts that allele frequencies will not change over time. it predicts that genotype frequencies will be predictable after a single generation. Actually, all of these describe the equation.

Actually, all of these describe the equation.

Factors that can cause microevolutionary changes away from equilibrium include all of the following EXCEPT: mutation. migration. genetic drift. natural selection. Actually, all of these factors can cause microevolution.

Actually, all of these factors can cause microevolution.

Genetic drift: affects populations in bottlenecks. is important in founder effects. has little role in large populations. leads to allele fixation. All of the above.

All of the above.

Testing to see if a population is at Hardy-Weinberg equilibrium requires all of the following EXCEPT: determining if selection is acting on the population. measuring or estimating the genotypic frequencies. calculating expected genotypic frequencies based on allele frequencies. conducting a statistical test, such as a Chi-square test. Actually, all of these are necessary steps.

determining if selection is acting on the population.

Depending on the environment and the genotypes involved, selection can produce all of the following effects EXCEPT: directional selection and eventual elimination of a recessive allele. directional selection and eventual elimination of a dominant allele. disruptive selection with the homozygotes being more fit than the heterozygotes. stabilizing selection, also known as overdominance. Actually, it can produce all of these effects.

directional selection and eventual elimination of a recessive allele.

All of the following describe effects of natural selection EXCEPT: it promotes adaptation. it reflects differential survival and reproduction according to phenotype. it always produces an equilibrium. it can lead to unstable equilibria. Actually, it is described by all of these.

it always produces an equilibrium.

Since random mating is an assumption of the Hardy-Weinberg equilibrium, non-random mating can confound it, as in all of the following cases EXCEPT: inbreeding. positive assortative mating. negative assortative mating. loss of heterozygosity. Actually, all of these are forms of non-random mating.

loss of heterozygosity.

The genetic effects of migration include all of the following EXCEPT to: counter the effect of genetic drift. make populations less heterogeneous. counter the effects of selection. allow new alleles to spread. Actually, all of these are effects of migration.

make populations less heterogeneous.

The Hardy-Weinberg equilibrium requires all of the following assumptions EXCEPT: mating is random. the population is small. no selection is taking place. there is no immigration or emigration. Actually, it requires all of these assumptions.

the population is small.