Deck 18: Microevolution: Changes Within Populations

Question 1

What is the natural selection that shifts the adaptation of an entire population called?

A)stabilizing selection
B)directional selection
C)disruptive selection
D)artificial selection

Answer 1

B

Question 2

The development of penicillin-resistant bacteria in the twentieth century represents an example of which of the following?

A)punctuated equilibrium
B)speciation
C)microevolution
D)mutation

Answer 2

D

Question 3

Which of the following defines characters between individuals that exist in two or more discrete states?

A)quantitative variation
B)qualitative variation
C)genetic variation
D)punctuated equilibrium

Answer 3

B

Question 4

Which of the following best describes the condition in which evolution could have taken place?

A)when a population experiences a shift in allele frequencies
B)when a mutation occurs in a population
C)when a feature of an individual animal changes through use or disuse
D)when a population has different forms of the same gene

Question 5

What is the evolution of the humpback whale an example of?

A)homology
B)microevolutionc macroevolution
C)analogy

Question 6

Which of the following best explains variation that approximates a bell-shaped curve when plotted on a bar graph?

A)The variation is undergoing disruptive selection.
B)The variation is undergoing stabilizing selection.
C)The variation is quantitative.
D)The variation is qualitative.

Question 7

Which of the following is a correct expression of the Hardy-Weinberg equation?

A)p² + 2pq + q² = 0
B)p² + pq − q² = 1
C)p² + 2pq + q² = 1
D)p + q = 0

Question 8

All of the population attributes listed below can be calculated with the Hardy-Weinberg equation EXCEPT which?

A)the frequency of heterozygotes
B)the frequency of a dominant allele
C)the frequency of a recessive allele
D)the frequency of mutation

Question 9

Which of the following best describes microevolution?

A)the formation of a new species
B)the occurrence of a new mutation
C)a change in allele frequencies within a population
D)the gradual change in the form of fossils over geological time

Question 10

Which of the following is describing the situation when microevolution takes place?

A)when a population experiences a shift in allele frequencies
B)when a mutation occurs in a population
C)when several mutations occur in a population
D)when a population has different forms of the same gene

Question 11

For which of the following is the Hardy-Weinberg formula valuable?

A)calculating changes in population size
B)calculating changes in speciation
C)calculating changes in allele frequencies
D)calculating changes in mutation

Question 12

Which of the following does directional selection favour?

A)intermediate phenotypes
B)phenotypes at one end of the distribution
C)phenotypic extremes at both ends
D)heterozygotes

Question 13

Which of the following processes listed below will NOT disrupt Hardy-Weinberg equilibrium?

A)nonrandom mating
B)natural selection
C)migration
D)punctuated equilibrium

Question 14

In which of the following sexually reproducing populations does the Hardy-Weinberg principle of genetic equilibrium tell us what to expect?

A)in a population that is decreasing with each generation
B)in a population that is increasing with each generation
C)in a population that is evolving
D)in a population that is not evolving

Question 15

Which of the following is NOT a condition for the genetic equilibrium?

A)The population is not migratory to other populations.
B)The population is closed to migration from other populations.
C)The population is infinite in size.
D)The population is small in size.

Question 16

In an isolated population of fruit flies, 4% of the individuals have pink eyes, a homozygous recessive condition, and 96% have the dominant black eye phenotype. What percentage of the population are heterozygotes?

A)4%
B)16%
C)32%
D)48%

Question 17

Which of the following is the most accurate definition of microevolution?

A)a heritable change in the genetics of a population over time
B)natural selection leading to adaptation over time
C)the occurrence of a series of mutations over time
D)the origin of major new forms of life over time

Question 18

What is the one measurement we have to make if we want to know the percentage of particular genotypes within an actual population, assuming complete dominance and two alleles?

A)the frequency of heterozygous phenotypes
B)the frequency of heterozygous genotypes
C)the frequency of dominant phenotypes
D)the frequency of recessive phenotypes

Question 19

Which of the following will disrupt Hardy-Weinberg equilibrium the least?

A)directional selection
B)stabilizing selection
C)migration
D)reduction to a small population size

Question 20

What would changing environmental conditions most likely cause in an existing species?

A)disruptive selection
B)mutation
C)directional selection
D)stabilizing selection

Question 21

Which process below is NOT an agent of microevolutionary change?

A)mutation
B)genetic drift
C)natural selection
D)random mating

Question 22

What is the production of random evolutionary changes in small breeding populations known as?

A)gene flow
B)genetic drift
C)disruptive selection
D)mutation

Question 23

What does "2pq" represents in the Hardy-Weinberg equation?

A)It represents the homozygous recessive genotypes.
B)It represents the heterozygous genotypes.
C)It represents the homozygous dominant genotypes.
D)It represents the heterozygous phenotypes.

Question 24

In a colony of 100 guinea pigs, 16 show the recessive trait of bristly hair. What is the frequency of the recessive allele in the population?

A)0.400
B)0.160
C)0.040
D)0.016

Question 25

Because of fluctuations in the environment, such as depletion of food supply or an outbreak of disease, a population may periodically experience a rapid and marked decrease in the number of individuals, leading to a form of genetic drift. What is this form of genetic drift called?

A)a founder effect
B)migration
C)gene flow
D)a genetic bottleneck

Question 26

Which of the following is the source of new alleles in a population?

A)natural selection
B)mutation
C)microevolution
D)genetic drift

Question 27

Which of the following is NOT an agent of microevolutionary change?

A)mutation
B)gene flow
C)random mating
D)genetic drift

Question 28

In a colony of 100 guinea pigs, 16 show the recessive trait of bristly hair. What is the percentage of heterozygotes in the population?

A)24%
B)36%
C)48%
D)52%

Question 29

According to the modern synthetic theory of evolution, what does the accumulation of mutations over time result in?

A)microevolution
B)adaptation
C)an increase in genetic variation
D)speciation

Question 30

Which process below is NOT a component of natural selection?

A)genetic drift
B)overproduction of offspring
C)limitations in vital resources
D)genetic variation

Question 31

What does a sudden reduction in population size generally result in?

A)extinction
B)mutation
C)speciation
D)genetic drift

Question 32

A baby is born with wrinkled, poorly-formed skin and blood vessels prone to rupturing. What can we say the baby has inherited?

A)a lethal mutation
B)a deleterious mutation
C)an advantageous mutation
D)a partial mutation

Question 33

In which of the following scenarios will genetic drift have a progressively larger impact on allele frequencies in a population?

A)when gene flow increases
B)when population size decreases
C)when mutation rate decreases
D)when random mating increases

Question 34

If individuals move from one population to another, it may cause a shift in allele frequencies. What causes this shift?

A)genetic drift
B)directional selection
C)mutation
D)gene flow

Question 35

Which of the following best characterize mutations that confer no apparent selective advantage or disadvantage in a particular environment?

A)random mutations
B)deleterious mutations
C)neutral mutations
D)stabilizing mutations

Question 36

Which of the following processes results in microevolution without any form of natural selection?

A)genetic drift
B)mutation
C)development of new characteristics during an individual's lifetime
D)genetic variation

Question 37

We are sending a small number of dogs to colonize a new planet. Through a random selection process, we end up only with dachshunds and Chihuahuas. The subsequent colony is all small dogs with short legs. What is this an example of?

A)adaptive radiation
B)punctuated equilibrium
C)genetic drift
D)microevolution

Question 38

Imagine that the only survivors of a colony on Venus are a man and a woman, who happen to be both originally from southern Ukraine. Which of the following will their descendants show?

A)genetic drift
B)punctuated equilibrium
C)excessive mutation
D)heterozygote advantage

Question 39

If the frequency of the recessive allele (q) for a particular two-allele gene in a population is 0.20, what percentage of the individuals in the population will be heterozygotes for that gene?

A)0.16
B)0.20
C)0.32
D)0.80

Question 40

There are two alleles for a gene in a population, and the frequency of the dominant allele (p) is 0.50. What is the frequency of the recessive allele (q) then?

A)0.05
B)0.25
C)0.50
D)0.75

Question 41

Under what circumstance might measuring the frequency of homozygous recessive genotypes lead to erroneous predictions of allele frequencies in a population?

A)The population is under Hardy-Weinberg equilibrium.
B)The population is affected by heterozygote advantage.
C)The population has undergone genetic drift in the past.
D)The population is affected by homozygote advantage.

Question 42

What is inbreeding primarily due to?

A)migration
B)nonrandom mating
C)mutation
D)adaptive radiation

Question 43

Which of the following is the least likely result of a genetic bottleneck?

A)an increase in the frequency of the less common allele
B)allele frequencies identical to the previous generation
C)a decrease in the frequency of an uncommon allele
D)a decrease in the frequency of the most common allele

Question 44

What is the decline in the occurrence of sickle cell anemia in the American population most likely the result of?

A)a lower mutation rate in the United States than in Africa
B)the advantage of both homozygous forms over the heterozygous form
C)the development of appropriate medical treatment for the sickle cell condition in the United States
D)a decline in the occurrence of malaria in the United States

Question 45

The distribution of the genetic disorder called sickle cell anemia is correlated with the distribution of malaria in tropical countries. What is this an example of?

A)heterozygote advantage
B)a genetic bottleneck
C)genetic drift
D)evolutionary convergence

Question 46

What is any product of natural selection that increases the relative fitness of an organism in its environment called?

A)mutation
B)adaptive trait
C)adaptation
D)variation

Question 47

If you wanted to calculate the frequencies of the two different alleles for a particular gene in a population, what data would you have to gather and how would you use it?

Question 48

How could parasitism by wasps and feeding by birds result in a higher percentage of galls (made by gall-making flies) of medium size rather than small or large galls (or an even percentage of all sizes of galls)?

Question 49

People with the disease known as sickle cell anemia are often better able to survive malaria. What is the cause of this?

A)balanced polymorphism
B)heterozygote advantage
C)disruptive selection
D)stabilizing selection

Question 50

What is the founder effect a type of?

A)natural selection
B)mutation
C)genetic drift
D)gene flow

Question 51

Intermediate forms are often absent in characters showing qualitative variation.

Question 52

Studies of chromosomal and mitochondrial DNA suggest that every locus exhibits some variability in its nucleotide sequence. Which of the following does NOT apply?

A)Every locus exhibits some variability in its nucleotide sequence among individuals from a single population.
B)Every locus exhibits some variability in its nucleotide sequence between populations of the same species.
C)Every locus exhibits some variability in its nucleotide sequence between related species.
D)Every locus exhibits some variability in its nucleotide sequence within an individual.

Question 53

Which evolution-related events are in the correct cause-and-effect sequence?

A)mutation → variation → natural selection → adaptation → speciation
B)variation → adaptation → mutation → natural selection → speciation
C)speciation → adaptation → variation → mutation → natural selection
D)mutation → speciation → adaptation → variation → natural selection

Question 54

Distinguish between quantitative and qualitative variation.

Question 55

What is the stable presence of more than one allele for a particular gene in a population called?

A)balanced polymorphism
B)mixed gene pool
C)mutation pressure
D)genetic drift

Question 56

What does natural selection result in?

A)adaptation
B)mutation
C)a new species
D)genetic drift

Question 57

How does gene flow introduce novel genetic variants into populations?

Question 58

What is the contribution that an individual makes to the gene pool of the next generation in relation to the contributions of other individuals called?

A)competition
B)genetic drift
C)relative fitness
D)gene flow

Question 59

Phenotypic variation CANNOT be passed on from one generation to the next.

Question 60

What is balanced polymorphism in a population likely the result of?

A)disruptive selection
B)sexual selection
C)directional selection
D)stabilizing selection

Question 61

Genetic drift can eliminate alleles from a population more quickly than natural selection.

Question 62

Match the Hardy-Weinberg factor with the correct genetic designation.
a.frequency of heterozygotes
b.frequency of the dominant allele
c.frequency of the recessive allele
d.the total gene pool for a gene with two alleles
e.frequency of homozygous recessive genotypes
f.frequency of homozygous dominant genotypes
q

Question 63

Match the Hardy-Weinberg factor with the correct genetic designation.
a.frequency of heterozygotes
b.frequency of the dominant allele
c.frequency of the recessive allele
d.the total gene pool for a gene with two alleles
e.frequency of homozygous recessive genotypes
f.frequency of homozygous dominant genotypes
p

Question 64

Match each of the following definitions with the correct agent.
a.gene flow
b.nonrandom mating
c.genetic drift
d.mutation
e.natural selection
random changes in allele frequencies caused by chance events

Question 65

If you were planning the colonization of a distant planet, what would you do to ensure that the population remained genetically healthy for a long time?

Question 66

Small populations on islands can be said to have experienced a form of genetic drift called the founders effect.

Question 67

Population bottleneck greatly reduces population size even if the population numbers later rebound.

Question 68

Genetic drift is non-selective and therefore does not contribute to microevolution.

Question 69

Match each of the following definitions with the correct agent.
a.gene flow
b.nonrandom mating
c.genetic drift
d.mutation
e.natural selection
choice of mates based on their phenotypes and genotypes

Question 70

New traits arise from scratch through the formation of a new gene.

Question 71

Match each of the following definitions with the correct agent.
a.gene flow
b.nonrandom mating
c.genetic drift
d.mutation
e.natural selection
differential survivorship or reproduction of individuals with different genotypes

Question 72

Natural selection results in organisms perfectly adapted to their environments.

Question 73

Match each of the following definitions with the correct agent.
a.gene flow
b.nonrandom mating
c.genetic drift
d.mutation
e.natural selection
change in allele frequencies as individuals join a population and reproduce

Question 74

Genetic variation can originate both from the production of new alleles and from the arrangement of existing alleles.

Question 75

Natural selection quickly eliminates harmful alleles from the population.

Question 76

How can organisms with the same phenotype have different genotypes and vice versa, and what is the significance?

Question 77

The reason why some specialty breeds of dogs are more prone to genetic disease is because of genetic drift.

Question 78

When multiple colour forms of an organism exist in a population, the least abundant form is likely to increase in frequency.

Question 79

In an unchanging environment, a well-adapted population is likely to experience no natural selection of any kind.

Question 80

Match each of the following definitions with the correct agent.
a.gene flow
b.nonrandom mating
c.genetic drift
d.mutation
e.natural selection
a heritable change in DNA