Question 1

Which of the following does not result in a decrease of genetic variation?
A) natural selection
B) genetic drift
C) bottleneck effect
D) founder effect
E) mutation

Accepted Answer

Mutation introduces new genetic variations into a population, increasing genetic diversity.

Question 2

Why does the malaria disease persist in the human population?
A) Too few humans have died of malaria to end the disease.
B) Multiple phenotypes survive in a balanced polymorphism.
C) Malaria is a recessive disease and few humans are ever sick.
D) Humans are protected from the malaria parasite.
E) The disease is under stabilizing selection.

Accepted Answer

Malaria persists in the human population because there are multiple phenotypes that survive in a balanced polymorphism. This means that while some individuals may be more susceptible to malaria and suffer from the disease, others may be less susceptible or asymptomatic carriers. As a result, the disease persists in the population without wiping out one particular phenotype.

Question 3

Which individual would be considered the fittest?
A) Individual that has the longest canine teeth within the group
B) Individual that has the greatest number of breeding opportunities
C) Individual that has the best camoflauge to avoid predators
D) Individual that controls the largest territory
E) Individual that has the greatest number of offspring

Accepted Answer

Fitness in evolutionary terms is defined as the ability of an individual to successfully pass on its genes to the next generation. Therefore, the individual that has the greatest number of offspring would be considered the fittest, as it has successfully passed on its genes and ensured their survival for the next generation.

Question 4

h  The figure shown here represents stabilizing selection.What happens when an individual is produced that possesses a trait far away from the mean value?
A) That extreme individual will likely not survive and reproduce.
B) That extreme individual will be more likely to survive and reproduce.
C) That extreme individual will have neither an advantage nor a disadvantage than other individuals.
D) All phenotypes have equal likelihood of surviving and reproducing.
E) The average phenotype is less likely to survive and reproduce.

Accepted Answer

Stabilizing selection favors individuals with the average phenotype and selects against individuals with extreme phenotypes. Therefore, an individual produced with a trait far away from the mean value will likely not be as fit as those individuals with traits closer to the mean value and will have a lesser chance of surviving and reproducing.

Question 5

In the Hardy-Weinberg formula,what does q² represent? A) frequency of the dominant allele B) frequency of the recessive allele C) frequency of the heterozygotes D) frequency of the homozygous dominants E) frequency of the homozygous recessives

Accepted Answer

The answer of In the Hardy-Weinberg formula,what does q² represent? A)...

Question 6

What statement is false regarding the differences between a biological species and subspecies?
A) Crosses between biological species cannot produce fertile offspring, crosses between subspecies can produce fertile offspring.
B) Subspecies are "races" within a single species.
C) Gene flow exists among different subspecies but not among species.
D) Greater degrees of allelic frequencies exist between species than among subspecies.
E) Phenotypes of different species are easily recognizable; little to no phenotypic variation exists among subspecies.

Accepted Answer

Phenotypic variation can exist among subspecies, and they may not always be easily distinguishable.

Question 7

Which of the following does not generate genetic variation within a population?
A) genetic recombination
B) independent assortment of alleles
C) sexual reproduction
D) mutations
E) adaptation

Accepted Answer

Adaptation does not generate genetic variation within a population. Instead, adaptation refers to the process by which populations become better suited to their environment through natural selection. Genetic recombination, independent assortment of alleles, sexual reproduction, and mutations all generate genetic variation within a population.

Question 8

What might occur in moth populations if pollution from industry was cleaned up,and the color of tree bark returned to its natural color?
A) Dark moths would continue to be the predominant phenotype.
B) Birds would now see the dark moths easier than the lighter color moths.
C) Dark- and light-colored moths would survive in equal numbers.
D) Both dark and light color moths would be preyed upon equally by birds.

Accepted Answer

If the pollution is cleaned up and the tree bark returns to its natural color, lighter moths would blend in better, making dark moths more visible to predators like birds.

Question 9

Which of the following examples is one of genetic drift?
A) A forest fire kills all plant life south of a highway.
B) Rabbits with longer fur survive the winter.
C) Insects resistant to insecticide survive crop dusting.
D) Colorful lizards living on brown leaves are most often eaten by predators.
E) Flowers with larger flowers attract more butterflies than smaller flowers.

Accepted Answer

Genetic drift refers to random changes in the frequency of alleles in a population. A forest fire killing all plant life south of a highway is an example of a random event that can cause genetic drift by randomly eliminating individuals, thus changing allele frequencies in the surviving population.

Question 10

Which Hardy-Weinberg condition is violated by sexual selection?
A) no mutations
B) no natural selection
C) random mating
D) no genetic drift
E) no gene flow

Accepted Answer

Sexual selection violates the Hardy-Weinberg condition of random mating as individuals with certain traits are more likely to mate than others, leading to non-random pairings.

Question 11

Why do prokaryotes and eukaryotes differ in their reliance on mutations for generating genetic variation?
A) Prokaryotes are smaller in size than eukaryotes.
B) Prokaryotes sexually reproduce, eukaryotes do not.
C) Eukaryotes sexually reproduce, prokaryotes do not.
D) Eukaryotes possess a nucleus, prokaryotes do not.
E) Prokaryotes are single-celled, eukaryotes are multicellular.

Accepted Answer

Eukaryotes rely on sexual reproduction, which involves recombination and independent assortment, to generate genetic variation, whereas prokaryotes primarily rely on mutations since they do not undergo sexual reproduction.

Question 12

If a population recovers to its original population size after experiencing a bottleneck,which statement is correct regarding this population?
A) The recovered population is as likely to go extinct as is the population prior to the bottleneck.
B) The bottleneck subjected the population to directional selection.
C) The recovered population shows less genetic diversity that the population prior to the bottleneck.
D) The recovered population shows more genetic diversity than the population prior to the bottleneck.
E) The recovered population is more likely to go extinct as is the population prior to the bottleneck

Accepted Answer

During a bottleneck, there is a reduction in genetic diversity due to the loss of individuals carrying different alleles. When the population recovers, it is limited to the remaining genetic diversity, which is less diverse than the population prior to the bottleneck. Therefore, the recovered population shows less genetic diversity than the population prior to the bottleneck.

Question 13

All of the genes and all of their associated alleles within a population represent the population's
A) genotype.
B) gene flow.
C) gene pool.
D) genome.
E) Hardy-Weinberg equilibrium.

Accepted Answer

The gene pool represents all of the genes and their associated alleles within a population.

Question 14

Which of the following is not one of the conditions required for Hardy-Weinberg equilibrium?
A) Mutations must not occur.
B) Natural selection must not occur.
C) Random mating must not occur.
D) Genetic drift must not occur.
E) Assortative mating must not occur.

Accepted Answer

Random mating is a requirement for Hardy-Weinberg equilibrium. Non-random mating, such as assortative mating or inbreeding, can lead to changes in allele frequencies and result in deviation from the equilibrium. The other conditions listed (mutations not occurring, no natural selection, no genetic drift) are also necessary for Hardy-Weinberg equilibrium.

Question 15

Which of the following is most likely to lead to two distinct species?
A) directional selection
B) stabilizing selection
C) disruptive selection
D) genetic drift
E) bottleneck effect

Accepted Answer

Disruptive selection favors extreme phenotypes over intermediate ones, causing the population to split into two distinct groups, each with its own unique set of adaptations. Over time, these two groups can become reproductively isolated from each other and evolve into separate species.

Question 16

If people with freckles preferentially mate with other people with freckles,this would be an example of
A) microevolution.
B) natural selection.
C) genetic drift.
D) nonrandom mating.
E) gene flow.

Accepted Answer

Nonrandom mating occurs when individuals have a preference for selecting mates with certain traits, in this case, freckles. This can affect the frequency of genes in a population but does not necessarily lead to significant evolutionary changes such as speciation. Therefore, this scenario represents nonrandom mating.

Question 17

What characteristic do a bottleneck and a founder effect have in common?
A) Both encounter a population crash.
B) Both involve a portion of a population becoming isolated.
C) Both involve a decrease in a population's genetic diversity.
D) Both affect the entire population.
E) Both are a type of natural selection.

Accepted Answer

Both a bottleneck and a founder effect result in a decrease in the genetic diversity of a population. In a bottleneck event, the population size is drastically reduced, and only a few individuals survive to reproduce, leading to a loss of genetic variation. In a founder effect, a small group of individuals separates from the larger population and establishes a new population, again leading to reduced genetic diversity due to the limited genetic makeup of the founding individuals.

Question 18

If the average leg size of a reptile continually got smaller through generations,this would be an example of
A) disruptive selection.
B) stabilizing selection.
C) directional selection.
D) genetic drift.
E) bottleneck effect.

Accepted Answer

Directional selection occurs when there is a consistent shift in one direction of a trait's distribution, leading to an increase or decrease in the frequency of certain traits. In this case, the average leg size of a reptile getting smaller over generations represents a consistent shift in one direction, which is smaller leg size. Therefore, this is an example of directional selection.

Question 19

If half of a population is homozygous recessive,what is p?
A) 0.5
B) 0.707
C) 0.25
D) 0.293
E) 0.1

Accepted Answer

The answer of If half of a population is homozygous...

Question 20

If p = 0.6,what is q?
A) 0.6
B) 0.4
C) 0.36
D) 0.15
E) 0

Accepted Answer

q = 1 - p = 1 - 0.6 = 0.4

Quiz 15: Evolution on a Small Scale

Which of the following does not result in a decrease of genetic variation?

Why does the malaria disease persist in the human population?

Which individual would be considered the fittest?

h The figure shown here represents stabilizing selection.What happens when an individual is produced that possesses a trait far away from the mean value?

In the Hardy-Weinberg formula,what does q2 represent?

What statement is false regarding the differences between a biological species and subspecies?

Which of the following does not generate genetic variation within a population?

What might occur in moth populations if pollution from industry was cleaned up,and the color of tree bark returned to its natural color?

Which of the following examples is one of genetic drift?

Which Hardy-Weinberg condition is violated by sexual selection?

Why do prokaryotes and eukaryotes differ in their reliance on mutations for generating genetic variation?

If a population recovers to its original population size after experiencing a bottleneck,which statement is correct regarding this population?

All of the genes and all of their associated alleles within a population represent the population's

Which of the following is not one of the conditions required for Hardy-Weinberg equilibrium?

Which of the following is most likely to lead to two distinct species?

If people with freckles preferentially mate with other people with freckles,this would be an example of

What characteristic do a bottleneck and a founder effect have in common?

If the average leg size of a reptile continually got smaller through generations,this would be an example of

If half of a population is homozygous recessive,what is p?

If p = 0.6,what is q?

In the Hardy-Weinberg formula,what does q² represent?