Deck 15: Evolution on a Small Scale

Question 1

Which of the following generates genetic variation within a population?

A) genetic recombination
B) independent assortment of alleles
C) sexual reproduction
D) mutation
E) All of the above answers describe ways that genetic variation is generated in a population.

Answer 1

E

Question 2

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 than 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.

Answer 2

C

Question 3

In the Hardy-Weinberg formula, what does q ² 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

Answer 3

E

Question 4

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-colored moths would continue to be the predominant phenotype.
B) Birds would see dark-colored moths more easily than light-colored moths and prey on dark-colored moths more frequently.
C) Dark- and light-colored moths would survive in equal numbers.
D) Birds would prey upon dark- and light-colored moths equally.
E) Selection would favor the hybrid offspring of dark and light moths.

Question 5

If people with freckles preferentially mated 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.

Question 6

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 likely will 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 over other individuals.
D) All phenotypes have equal likelihood of surviving and reproducing.
E) The average phenotype is less likely to survive and reproduce.

Question 7

Polydactylism (possessing more than five fingers per hand) within the Amish population in Pennsylvania isconsidered an example of the founder effect. This is because the frequency of polydactylism among the Amish in Pennsylvania is identical to its frequency among the Amish population in Germany.

Question 8

If p = 0.6, what is q?

A) 0.6
B) 0.4
C) 0.36
D) 0.15
E) 0

Question 9

In regards to natural selection, which of the following individuals would be considered the most fit?

A) the individual that has the longest canine teeth
B) the individual that has the greatest number of breeding opportunities
C) the individual that has the best camouflage to avoid predators
D) the individual that controls the largest territory
E) the individual that has the greatest number of offspring

Question 10

Which of the following could increase genetic variation?

A) natural selection
B) genetic drift
C) bottleneck effect
D) founder effect
E) mutation

Question 11

Which of the following examples describes 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) Plants with larger flowers attract more butterflies than plants with smaller flowers.

Question 12

The conditions required by the Hardy-Weinberg equilibrium are commonly found in nature.

Question 13

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

Question 14

Which of the following is a condition required for a Hardy-Weinberg equilibrium?

A) Mutations must not occur.
B) Natural selection must not occur.
C) Random mating must occur.
D) Genetic drift must not occur.
E) All of the above are conditions required for Hardy-Weinberg Equilibrium.

Question 15

Natural selection can favor directional, stabilizing, and disruptive selection in the same population simultaneously.

Question 16

Dominat alleles are always the most common.

Question 17

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

Question 18

What characteristic is common of both a genetic bottleneck and a founder effect?

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.

Question 19

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

A) genotype.
B) gene flow.
C) gene pool.
D) genome.
E) Hardy-Weinberg equilibrium.

Question 20

If the average tail 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.

Question 21

A female peacock chooses a mate based on his showy plumage and courtship dance. This is an example of

A) random mating.
B) assortative mating.
C) sexual selection.
D) gene flow.
E) natural selection.

Question 22

A group of field mice crosses a highway and joins a new population of field mice on the other side, producing offspring with this population. This is an example of

A) gene flow.
B) genetic drift.
C) Hardy-Weinberg equilibrium.
D) assortative mating.
E) hybridization.

Question 23

Why does malaria persist in the human population?

A) Too few humans have died of malaria to end the disease.
B) Heterozygote advantage maintains both the normal allele and the sickle cell allele in the population.
C) Malaria is a recessive disease and few humans contract it.
D) Humans are protected from the malaria parasite.
E) Malaria is under stabilizing selection.

Question 24

Today, cheetahs show extreme genetic similarity. This is evidence of

A) past gene flow.
B) a past bottleneck event.
C) a history of directional selection.
D) a history of few genetic mutations.
E) assortative mating.

Question 25

Microevolution is influenced by which of the following?

A) mutation
B) gene flow
C) natural selection
D) genetic drift
E) All of the above answers describe factors that influence microevolution.

Question 26

The usage of the insecticide DDT to control mosquitoes resulted in

A) directional selection to insecticide resistance in the insects.
B) stabilizing selection to insecticide resistance in the insects.
C) disruptive selection to insecticide resistance in the insects.
D) genetic drift to insecticide resistance in the insects.
E) no change in the insect population.

Question 27

A population of bacteria is not in Hardy-Weinberg equilibrium. Through repeated exposure to an antibiotic, the frequency of a recessive allele is rapidly increasing. What is the most likely explanation for this response?

A) The recessive allele is responsible for susceptibility of the bacteria to the antibiotic.
B) The dominant allele is responsible for susceptibility of the bacteria to the antibiotic.
C) The recessive allele is responsible for resistance of the bacteria to the antibiotic.
D) The population is experiencing gene flow.
E) The population is experiencing disruptive selection.

Question 28

A fraction of a green frog population survives a hurricane to reproduce and generate a new population. This event is an example of

A) natural selection.
B) genetic drift.
C) founder effect.
D) industrial melanism.
E) gene flow.

Question 29

What is the genotype of an individual that has protection from both sickle-cell disease and malaria?

A) Hb ^AHb ^A
B) Hb ^AHb ^S
C) Hb ^SHb ^S
D) Hb ^S Hb ^s
E) Hb ^A Hb ^a

Question 30

The members of a population survive and successfully reproduce due to the specific phenotypes they posses. This is an example of

A) natural selection.
B) genetic drift.
C) founder effect.
D) industrial melanism.
E) gene flow.

Question 31

Directional selection in the modern horse is demonstrated by

A) populations consisting of only very dark and very light colored horses.
B) the rapid decrease in size over the last 200 years.
C) the gradual increase in size over millions of years.
D) fossils which show the horse has not changed in millions of years.
E) the extinction of other horse species.

Question 32

Biotic environments that influence natural selection include all but which of the following?

A) competition
B) predation
C) parasitism
D) weather
E) disease

Question 33

In the process of natural selection, individuals that are most fit are the ones that

A) survive the longest.
B) reproduce the most.
C) migrate every year.
D) have the most genetic mutations.
E) are the most physically fit.

Question 34

Which of the following is most likely to result in the formation of two distinct species?

A) directional selection
B) stabilizing selection
C) disruptive selection
D) genetic drift
E) bottleneck effect

Question 35

The increase in frequency of dark phenotypes in response to increased pollution is called

A) genetic drift.
B) founder effect.
C) industrial melanism.
D) assortative mating.
E) stabilizing selection.

Question 36

British land snails primarily occur in two extreme phenotypes. This is an example of

A) directional selection.
B) stabilizing selection.
C) disruptive selection.
D) genetic drift.
E) mutation.

Question 37

If p ² = 0.04, what is the frequency of homozygous recessives in the population?

A) 0.04
B) 0.2
C) 0.32
D) 0.64
E) 0.8

Question 38

In random mating

A) individuals choose the most attractive mate.
B) there is no factor influencing mate choice.
C) breeding occurs between two different species.
D) breeding occurs between two different subspecies.
E) fertile offspring are not produced.

Question 39

In what type of environment is being heterozygous in regards to the sickle-cell trait an advantage?

A) an environment that has malaria
B) an environment that is malaria-free
C) an environment that is exposed to a large amount of sunlight year-round
D) a polluted environment
E) an environment that is cold and rainy