Bio Quiz 4 Chap 20

Coloration in the peppered moth (Biston betularia) is determined by a single gene with two alleles showing complete dominance. Dark moths are homozygous dominant or heterozygous for the gene, light moths are homozygous recessive. In a sample of 100 moths, you determine that 64 of the moths are dark. According to the Hardy-Weinberg rule, the expected frequency of the dominant allele is ___. A. 0.4 B. 0.36 C. 0.6 D. 0.64 E. cannot be determined

A. 0.4

A fur color gene in rabbits has a white dominant (W) and brown recessive allele (w). The environment changes suddenly and none of the white rabbits survive. In a population of 10,000 rabbits the initial frequency of W in the pool was 0.7. How many generations would be required to eliminate all W alleles from the population? Assume that there is no mutation and the population meets all other Hardy-Weinberg conditions. A. 1 B. 2 C. 5 D. 20 E. can never be eliminated

A. 1

The organism with the highest fitness is: A. An animal that lives 10 years and produces 10 offspring per year. B. An animal that lives one year and produces 10 offspring total. C. An animal that lives 100 years and produces 10 offspring total. D. An animal that lives 2 years and produces 10 offspring per year. E. An animal that lives 10 years and produces 2 offspring per year.

A. An animal that lives 10 years and produces 10 offspring per year.

Some flowering plants cannot self-pollinate which increases their tendency to mate with phenotypically different mates, a process called disassortative mating. What effect would this have on a population in Hardy-Weinberg equilibrium? A. An increase in heterozygotes would be observed. B. An increase in homozygotes would be observed. C. A decrease in heterozygotes would be observed. D. The population would remain in Hardy-Weinberg equilibrium. E. No change homozygotes or heterozygotes would be observed.

A. An increase in heterozygotes would be observed.

The observation that most pureblood Native Americans have type O blood is best explained by _____ A. a founder effect. B. assortative mating. C. gene flow. D. genetic drift. E. frequent mutations.

A. a founder effect

Moths that can evade a bat's echolocation have _____ that increase their likelihood of survival and reproduction. A. adaptations B. genes C. fitness D. mutations E. selection

A. adaptations

During a drought on the Galapagos islands, finches with larger beaks were able to crack the large tough seeds produced by plants that survived the dry conditions. This is an example of ____. A. directional selection B. genetic drift C. stabilizing selection D. a founder effect E. disruptive selection

A. directional selection

In early ancestors of the modern giraffe, longer necks allowed animals to reach higher tree branches as food. This would lead to ____ in the ancestral giraffe population. A. directional selection B. genetic drift C. sexual selection D. stabilizing selection E. disruptive selection

A. directional selection

When fisheries managers move fish from one lake to another, this causes gene ______. A. flow B. blending C. mutation D. dominance

A. flow

There are more than 30 blood group genes in humans, in addition to the ABO locus. This increases ____ in human populations. A. genetic variability B. homozygosity C. selective mating D. gene flow E. founder effects

A. genetic variability

Gene flow, defined as the movement of genes from one population to another, can take place by migration, as well as A. mating between individuals of adjacent populations. B. mating with dominant phenotypes. C. mating with certain trait-containing individuals. D. physical movement of genes within an individual by transposons. E. removing the barriers between the populations.

A. mating between individuals of adjacent populations.

The genetic preservation of the features that increase the likelihood of survival and reproduction of some individuals within a population is called the process of A. natural selection. B. genetic drift. C. increasing evolutionary resistance. D. outcrossing. E. creation of new species.

A. natural selection

Many male songbirds are brightly colored. However, the color of the birds is determined by a balance of A. natural selection against bright colors by predation and sexual selection in favor of bright colors. B. mutations that reduce bright colors and gene flow in favor of bright colors. C. mutations that reduce bright colors and sexual selection in favor of bright colors. D. natural selection against bright colors by predation and mutations that introduce bright colors. E. gene flow that reduces bright colors and natural selection in favor of bright colors.

A. natural selection against bright colors by predation and sexual selection in favor of bright colors.

In the Hardy-Weinberg equations, the frequencies of 2 alleles in a population (where there are only 2 alleles to consider) can be designated as A. p and q. B. p2 and q2. C. 2pq. D. 1 - p and 1 - q. E. (p + q)2.

A. p and q

In order for natural selection to occur within a population, certain conditions must be met. One such condition is A. phenotypic variations that are genetic. B. heterozygosity must be very low. C. phenotypic differences resulting from environmental conditions. D. low rates of immigration. E. frequent mutations that are inherited.

A. phenotypic variations that are genetic.

The presence of the disease sickle cell anemia illustrates that natural selection does not always eliminate _________ alleles. A. recessive B. neutral C. dominant D. polymorphic

A. recessive

Natural selection, as a mechanism of evolution that, acts on variants within populations and ultimately leads to the evolution of different species was proposed by A. Lyell. B. Darwin. C. Mendel. D. Founder. E. Malthus.

B. Darwin

Two parents who do not have sickle cell anemia have a child that has the disease. The parents are both: A. Homozygous for the sickle cell allele B. Heterozygous for the sickle cell allele C. Homozygous for the normal allele D. Epistatic for the sickle cell allele E. Pleiotropic for the sickle cell allele

B. Heterozygous for the sickle cell allele

The disease, sickle-cell anemia is common in malaria-infested areas because individuals that are heterozygous for the gene (AS) have enhanced resistance to malaria over normal individuals (AA). Individuals with severe sickle-cell anemia (SS) usually die before reproduction. If this population moves to an area without malaria, what will happen to the allele frequency of the A allele over time? A. It will go up because there is no sickle cell anemia. B. It will go up because there is no malaria. C. It will go down because there is no malaria. D. It will go down because there is no sickle cell anemia.

B. It will go up because there is no malaria.

"The inheritance of acquired characteristics" proposal was put forward by A. Wallace. B. Lamarck. C. Hardy-Weinberg. D. Founder. E. Darwin.

B. Lamarck.

____ would produce the smallest evolutionary change in a given period of time in a population of birds. A. Migration B. Mutation C. Assortive mating D. Natural selection E. Gene flow

B. Mutation

Female cardinals select male mates in part based on their bright red color. What effect would this have on a cardinal population that was in Hardy-Weinberg equilibrium? A. The red allele frequencies would decrease because of equilibrium. B. The frequency of red alleles would be greater than those predicted by Hardy-Weinberg equilibrium. C. The red allele frequencies would remain unchanged because of equilibrium. D. The frequency of red alleles would be less than those predicted by Hardy-Weinberg equilibrium. E. The frequency of red alleles would be equal to those predicted by Hardy-Weinberg equilibrium.

B. The frequency of red alleles would be greater than those predicted by Hardy-Weinberg equilibrium.

A population of lizards lives in a rocky area next to a desert. Some lizards are light colored and blend into the sand. Others are dark and blend into the rocks. What may happen to this population of lizards over time? A. They may remain one species as a result of disruptive selection. B. They may evolve into two separate species as a result of disruptive selection. C. They may evolve into two separate species as a result of directional selection. D. They may remain one species as a result of stabilizing selection. E. They may remain one species as a result of directional selection.

B. They may evolve into two separate species as a result of disruptive selection.

Based on the graph above, the color of male guppies can be seen as a balance between positive and negative selections. Bright colors are an advantage in _____, but a disadvantage in _____. A. avoiding predators; attracting mates B. attracting mates; avoiding predators C. avoiding predators; finding food D. attracting mates; finding food E. finding food; attracting mates

B. attracting mates; avoiding predators

Darwin proposed that natural selection occurs in an environment by A. favoring those individuals with the most favorable acquired characteristics. B. favoring heritable features that make the organism better suited to survive and reproduce. C. producing a constant number of offspring while in that environment. D. resisting the environment and keeping the environment from changing. E. surviving for a fixed amount of time.

B. favoring heritable features that make the organism better suited to survive and reproduce.

Average human males are most likely to be attracted to women with a waist to hip ratio of 0.72. Women with this waist to hip ratio are also the most fertile. By being attracted to women with a waist to hip ratio, a male is increasing his chances of having children and thus improve his ____ . A. longevity B. fitness C. gene flow D. allele frequency

B. fitness

Large ears is a rare trait in a mainland population of mice. A female mice homozygous for very large ears arrives at an island that already contains mice after sneaking onto a boat. This will lead to a population with a higher incidence of big ears than the mainland population because of ____ A. natural selection. B. gene flow. C. a bottleneck effect. D. increased mutation. E. genetic drift.

B. gene flow

In a small population of cockroaches living in your kitchen, only a few roaches mate in one year. This can lead to random changes in allele frequency in the population through ______ A. selection. B. genetic drift. C. mutation. D. nonrandom mating. E. migration.

B. genetic drift

People homozygous for the sickle-cell anemia allele develop a life threatening disease, while those homozygous for the normal allele are at the highest risk of dying from malaria. Carriers have some resistance to malaria, but do not develop sickle cell anemia. This is an example of ____ A. founder effect. B. heterozygote advantage. C. genetic bottleneck. D. heterozygosity. E. point mutation.

B. heterozygote advantage.

Animals that select mates that are phenotypically similar will have _____ when compared with Hardy-Weinberg predictions. A. less natural selection B. more homozygotes. C. fewer homozygotes D. more heterozygotes E. more mutations

B. more homozygotes.

An island is on the migration route of sea birds. This island also has abundant tree nesting birds that live on the island permanently and are not found on any other island. The tree nesting birds are more likely than the sea birds to be in Hardy-Weinberg equilibrium because: A. the sea bird population is larger. B. of high immigration in the sea bird population. C. there are fewer mutations in the sea birds. D. mating is random in the tree nesting birds. E. natural selection is stronger in the tree nesting birds.

B. of high immigration in the sea bird population.

In the experiment above, guppy color patterns (spots) were measured in populations exposed to increasing amounts of predation. From this you could conclude that ____ . A. predators do not affect the color patterns of guppies B. predators are more likely to catch and eat brightly colored guppies C. evolutionary changes take millions of years to appear D. brightly colored guppies are more likely to reproduce in the presence of predators E. predators are less likely to catch and eat brightly colored guppies

B. predators are more likely to catch and eat brightly colored guppies

The midrange of an array of phenotypes is favored in ____. A. gene flow B. stabilizing selection C. directional selection D. disruptive selection E. genetic drift

B. stabilizing selection

If the frequency of an autosomal recessive trait in humans is 1 out of 100 births, what would be the expected frequency of heterozygote carriers for the trait if we assume that the gene is in Hardy-Weinberg equilibrium? A. 0.01 B. 0.10 C. 0.18 D. 0.81 E. 0.90

C. 0.18

For a gene with two alternative alleles, A (with a frequency of p) and B (with a frequency of q), the term in the algebraic form of the Hardy-Weinberg equilibrium for the heterozygote genotype frequency is A. p2. B. q2. C. 2pq. D. (p+q)2. E. 2Aa.

C. 2pq

You are studying a population of geese in which there are two color phases, brown and gray. Color in this species is controlled by a single gene, with brown dominant to gray. A random sample of 250 geese shows that 210 are brown. What percentage of the brown geese are heterozygous? (Assume that the population is in Hardy-Weinberg equilibrium.) A. 36% B. 43% C. 48% D. 57% E. 84%

C. 48%

In a large population of randomly reproducing rabbits, a recessive allele r comprises 80% of the alleles for a gene. What percentage of the rabbits would you expect to have the recessive phenotype? A. 4% B. 32% C. 64% D. 80% E. 100%

C. 64%

In the graph above, how can the change in infant mortality be explained as birth weight increases from 2 to 7 pounds? A. A larger baby will have more developed organs and thus have lower fitness. B. A larger baby will not be able to be delivered safely and thus have lower fitness. C. A larger baby will have more developed organs and thus have greater fitness. D. There is no correlation between birth weight and survival. E. A larger baby will not be able to be delivered safely and thus have higher fitness.

C. A larger baby will have more developed organs and thus have greater fitness.

______ could not be involved in gene flow? A. Gametes dispersed by ocean currents B. Wind-blown pollen C. Disassortative mating within a population D. Zygotes dispersed by ocean currents E. Hybridization between neighboring populations

C. Disassortative mating within a population

Genotypes are said to be in ___________ equilibrium if there is random mating and no other forces tend to alter the proportions of alleles from one generation to the next. A. homeostatic B. steady state C. Hardy-Weinberg D. Mendelian

C. Hardy-Weinberg

Natural selection for a certain phenotype will affect the _____ . A. genotype of a population. B. genotype of an individual. C. allele frequency of a population. D. allele frequency of an individual.

C. allele frequency of a population.

You spray your kitchen with an insecticide to kill the cockroaches. A few survive and reproduce, producing a large healthy population in a few generations that all have similar genetic backgrounds. This is an example of _____ A. migration. B. mutation. C. bottleneck effect. D. genetic drift. E. assortative mating.

C. bottleneck effect

Assortative and disassortative mating are similar in that both ____ A. change both the expected Hardy-Weinberg allele and genotype frequencies in a population. B. are kinds of selection pressure. C. change only the expected Hardy-Weinberg genotype frequencies in a population. D. are examples of random mating. E. change only the expected Hardy-Weinberg allele frequencies in a population.

C. change only the expected Hardy-Weinberg genotype frequencies in a population.

In a forest, trees that get more sunlight grow taller than other nearby trees. This is a form of ______ A. disruptive selection. B. artificial selection. C. directional selection. D. stabilizing selection. E. natural selection.

C. directional selection

Reproductive success of an individual is known as: A. macroevolution. B. variation. C. fitness. D. adaptive makeup. E. microevolution.

C. fitness

Certain small towns in the western United States have remained isolated and inbred since their settlement many years ago. Some alleles are more common in these communities as compared to the rest of the population. This effect is known as A. directional selection. B. disrupting selection. C. founder effect. D. Hardy-Weinberg principle. E. artificial selection.

C. founder effect.

The several hundred species of picture-winged fruit flies of the Hawaiian Islands are genetically very similar, yet they all differ markedly from their ancestral population in Asia. This is probably an example of _____ A. directional selection. B. sexual selection. C. founder effect. D. gene flow. E. disruptive selection.

C. founder effect.

The percentage of different colored water boatmen eaten by fish were graphed relative to the frequency of that color in the population. Based on the graph, a population of water boatmen would _____ A. increase in size. B. decrease in genetic variability. C. increase in rare genotypes. D. have no variation in genotype frequencies. E. lose rare genotypes

C. increase in rare genotypes.

About 80% of the alleles present in thoroughbred horses can be dated back to 31 known ancestors from the late eighteenth century. As a result, one would expect _____ A. Hardy-Weinberg equilibrium. B. low rates of mutation. C. little variation in physiology and behavior. D. random mating. E. many polymorphic alleles.

C. little variation in physiology and behavior.

The frequency of a particular allele within a population can be changed, over time, by A. genetic outflow. B. large population size. C. selection. D. inheritance of acquired characteristics. E. random mating.

C. selection

The California populations of the Northern elephant seal are descendants from a very small population of seals that was over-hunted in the 1890s. Heterozygosity in this population would be expected to be ________ due to _______________. A. great; disruptive selection B. slight; the founder effect C. slight; a bottleneck effect D. great; assortive mating E. great; a bottleneck effect

C. slight; a bottleneck effect

In disruptive selection, over time A. the population is strongly selected for in one direction (e.g., larger beak size). B. a population goes extinct. C. the population is strongly selected for in two directions (e.g., larger beak size and smaller beak size). D. the most extreme outliers of a population are eliminated (e.g., the largest beaks and smallest beaks are eliminated). E. a population increases its variation (e.g., a wide selection of all beak sizes).

C. the population is strongly selected for in two directions (e.g., larger beak size and smaller beak size).

Antigens on red blood cells are hereditary traits that allow blood to be typed in different ways. One system is based on a gene with two alleles, M and N. If the frequency of the M allele in a population is 0.4, then according to the Hardy-Weinberg rule, the expected frequency of the heterozygous MN genotype is ___. A. 0.16 B. 0.24 C. 0.36 D. 0.48 E. 0.6

D. 0.48

A human autosomal recessive trait appears in 1 in 100 births. What percent of people homozygous dominant for this trait? A. 0.01 B. 0.10 C. 0.18 D. 0.81 E. 0.90

D. 0.81

______ would be expected to produce the largest evolutionary change in a given period of time in a population of birds. A. Random mating B. Hardy-Weinberg equilibrium C. Mutation D. Migration E. Natural selection

D. Migration

____ would keep a population in Hardy-Weinberg equilibrium. A. Mutation B. Gene flow C. Genetic drift D. Random mating E. Selection

D. Random mating

In the graph above, which aspects of fitness would explain the percent infant mortality curve? A. The baby needs to be small enough to survive after birth, but large enough for a safe delivery. B. The larger the baby the better the chance of survival. C. The smaller the baby the better the chance of survival. D. The baby needs to be large enough to survive after birth, but small enough for a safe delivery. E. There is no correlation between birth weight and survival.

D. The baby needs to be large enough to survive after birth, but small enough for a safe delivery.

Being born with extra fingers on a hand is called polydactyly. This is more common in some populations in North America than others due to ____. A. an increase in mutation rate in these populations B. random mating with other populations in North America C. migration of people with multiple fingers out of the population D. a founder effect because their ancestors from Europe carried the alleles E. natural selection in favor of extra fingers in these populations

D. a founder effect because their ancestors from Europe carried the alleles

A restriction in genetic variability caused by a drastic reduction in population size is called a A. Hardy-Weinberg effect. B. polymorphic effect. C. adaptive effect. D. bottleneck effect. E. founder effect.

D. bottleneck effect

The key point in Darwin's proposal is that the ___________ imposes the conditions that determine the direction of selection. A. individual B. gene C. parent D. environment

D. environment

If a population was in Hardy-Weinberg equilibrium then ____ would occur in that population. A. natural selection B. assortive mating C. directional selection D. no evolutionary changes E. an increase of recessive alleles

D. no evolutionary changes

Cheetahs have been through a genetic bottleneck; evidence for this is that A. they originally came from small areas of Africa. B. the body is long, thin, and graceful. C. little natural selection occurs in this species. D. there is very little genetic variability. E. these cats are members of an endangered species.

D. there is very little genetic variability.

The recessive phenotype of a trait occurs in 16% of a population. What is the frequency of the dominant allele? A. 0.16 B. 0.36 C. 0.40 D. 0.48 E. 0.60

E. 0.60

A population of flowers is in Hardy-Weinberg equilibrium with an allele frequency for white flowers (w) of 40%. What percentage of the flowers will have the colored or dominant phenotype? A. 16% B. 25% C. 40% D. 60% E. 84%

E. 84%

Hardy-Weinberg pointed out that the original proportions of the genotypes in a population would remain constant from generation to generation if certain assumptions are met. Which one of the following is not a Hardy-Weinberg condition? A. No selection occurs. B. Random mating occurs. C. No gene flow occurs. D. The population is very large. E. No polymorphic loci exist in the population.

E. No polymorphic loci exist in the population.

In the Hardy-Weinberg equation, p and q are _____. A. mutation rates B. phenotypes C. genotypes D. measures of fitness E. allele frequencies

E. allele frequencies

The total of all the alleles of a gene in a population affects the: A. gene frequency B. size of the genome C. population size D. variant genes E. allele frequency

E. allele frequency

Both extremes of an array of phenotypes are favored in _____ . A. directional selection B. genetic drift C. gene flow D. stabilizing selection E. disruptive selection

E. disruptive selection

An insect population that becomes resistant to a commonly used insecticide is an example of _____. A. a founder effect B. gene flow C. disruptive selection D. genetic drift E. natural selection

E. natural selection

In some instances environmental change causes a situation where one phenotype is favored for a period of time, and then a different phenotype is favored. This oscillating selection causes A. extinction of the population. B. elimination of rarer genotypes because of uneven selection. C. an increase in point mutations. D. high population increase to maintain phenotypic variation. E. the maintenance of genetic variation in the population.

E. the maintenance of genetic variation in the population.