Question 1

In a population of 200 mice,brown fur is dominant to gray fur.If 120 of the 200 mice have brown fur,what is the frequency of mice that are heterozygous?

Accepted Answer

A) 46% 
B) 23% 
C) 37% 
D) 63% 
A) 46% 
B) 23% 
C) 37% 
D) 63%

Question 2

Please use the following information to answer the questions below.
A large population of laboratory animals has been allowed to breed randomly for a number of generations.After several generations,25% of the animals display a recessive trait (aa),the same percentage as at the beginning of the breeding program.The rest of the animals show the dominant phenotype,with heterozygotes indistinguishable from the homozygous dominants.
-What is the estimated frequency of allele A in the gene pool?

Accepted Answer

A) 0.25 
B) 0.50 
C) 0.75 
D) 0.125 
A) 0.25 
B) 0.50 
C) 0.75 
D) 0.125

Question 3

The restriction enzymes of bacteria protect the bacteria from successful attack by bacteriophages,whose genomes can be degraded by the restriction enzymes.The bacterial genomes are not vulnerable to these restriction enzymes because bacterial DNA is methylated.This situation selects for bacteriophages whose genomes are also methylated.As new strains of resistant bacteriophages become more prevalent,this in turn selects for bacteria whose genomes are not methylated and whose restriction enzymes instead degrade methylated DNA.The outcome of the conflict between bacteria and bacteriophage at any point in time results from

Accepted Answer

A) frequency-dependent selection. 
B) evolutionary imbalance. 
C) heterozygote advantage. 
D) neutral variation. 
A) frequency-dependent selection. 
B) evolutionary imbalance. 
C) heterozygote advantage. 
D) neutral variation.

Question 4

Which of the following consistently improves the degree to which organisms are well suited for life in their environment?

Accepted Answer

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

Question 5

What is the Hardy-Weinberg equation?

Accepted Answer

A) an assessment of evolution at a particular locus 
B) a determination of allele frequency 
C) a determination of genotype frequency 
D) an assessment of heterozygosity in a population 
A) an assessment of evolution at a particular locus 
B) a determination of allele frequency 
C) a determination of genotype frequency 
D) an assessment of heterozygosity in a population

Question 6

Which process in sexual reproduction results in diversity at the nucleotide level?

Accepted Answer

A) chromosome shuffling 
B) chromosome crossover 
C) independent assortment of chromosomes 
D) random distribution of chromosomes 
A) chromosome shuffling 
B) chromosome crossover 
C) independent assortment of chromosomes 
D) random distribution of chromosomes

Question 7

Mountains also have an unmatched power to drive human evolution.Starting tens of thousands of years ago,people moved to high altitudes,and there they experienced natural selection that has reworked their biology.In Tibet,for example,people have broader arteries and capillaries.In the Andes,they can dissolve more oxygen into their blood.These different traits of people who live in high altitudes illustrate

Accepted Answer

A) stabilizing evolution. 
B) sexual selection. 
C) adaptive evolution. 
D) acclimatization. 
A) stabilizing evolution. 
B) sexual selection. 
C) adaptive evolution. 
D) acclimatization.

Question 8

In the formula for determining a population's genotype frequencies,the pq in the term 2pq is necessary because

Accepted Answer

A) the population is diploid. 
B) heterozygotes can come about in two ways. 
C) the population is doubling in number. 
D) heterozygotes have two alleles. 
A) the population is diploid. 
B) heterozygotes can come about in two ways. 
C) the population is doubling in number. 
D) heterozygotes have two alleles.

Question 9

Please use the following information to answer the questions below.
In those parts of equatorial Africa where the malaria parasite is most common,the sickle-cell allele constitutes 20% of the β hemoglobin alleles in the human gene pool.
-With respect to the sickle-cell allele,what should be true of the ? hemoglobin locus in U.S.populations of African Americans whose ancestors were from equatorial Africa?
1)The average heterozygosity at this locus should be decreasing over time.
2)There is an increasing heterozygote advantage at this locus.
3)Diploidy is helping to preserve the sickle-cell allele at this locus.
4)Frequency-dependent selection is helping to preserve the sickle-cell allele at this locus.

Accepted Answer

A) 1 only 
B) 1 and 3 
C) 2 and 3 
D) 1,2,and 3 
E) 1,2,and 4 
A) 1 only 
B) 1 and 3 
C) 2 and 3 
D) 1,2,and 3 
E) 1,2,and 4

Question 10

The frequency of a disease is 30/1000.This is a disease that follows a dominant/recessive pattern of inheritance on one gene (where the only affected individuals are all homozygous recessive).What is the frequency of the disease genotype q2?

Accepted Answer

A) 3% 
B) 13% 
C) 6% 
D) 30% 
A) 3% 
B) 13% 
C) 6% 
D) 30%

Question 11

What is true of natural selection?

Accepted Answer

A) Natural selection is a random process. 
B) Natural selection creates beneficial mutations. 
C) The only way to eliminate harmful mutations is through natural selection. 
D) Mutations occur at random;natural selection can preserve and distribute beneficial mutations. 
A) Natural selection is a random process. 
B) Natural selection creates beneficial mutations. 
C) The only way to eliminate harmful mutations is through natural selection. 
D) Mutations occur at random;natural selection can preserve and distribute beneficial mutations.

Question 12

How can genetic variation at the whole gene level (gene variability)be quantified?

Accepted Answer

A) by the average percentage of loci that are heterozygous 
B) by the average percentage of loci that are homozygous 
C) by nucleotide variability 
D) by the differences in noncoding DNA 
A) by the average percentage of loci that are heterozygous 
B) by the average percentage of loci that are homozygous 
C) by nucleotide variability 
D) by the differences in noncoding DNA

Question 13

Which of the following is most likely to produce an African butterfly species in the wild whose members have one pattern?

Accepted Answer

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

Question 14

Please use the following information to answer the question(s)below.
  
-Examining the figure,which type of selection eliminates extreme frequency of individuals' phenotype?

Accepted Answer

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

Question 15

In the formula for determining a population's genotype frequencies,the 2 in the term 2pq is necessary because

Accepted Answer

A) the population is diploid. 
B) heterozygotes can come about in two ways based upon parental gametes. 
C) the population is doubling in number. 
D) heterozygotes have two alleles. 
A) the population is diploid. 
B) heterozygotes can come about in two ways based upon parental gametes. 
C) the population is doubling in number. 
D) heterozygotes have two alleles.

Question 16

Adult male humans generally have deeper voices than do adult female humans,which is the direct result of higher levels of testosterone causing growth of the larynx.If the fossil records of apes and humans alike show a trend toward decreasing larynx size in adult females and increasing larynx size in adult males,then

Accepted Answer

A) sexual dimorphism was developing over time in these species. 
B) intrasexual selection seems to have occurred. 
C) stabilizing selection was occurring in these species concerning larynx size. 
D) selection was acting more directly upon genotype than upon phenotype. 
A) sexual dimorphism was developing over time in these species. 
B) intrasexual selection seems to have occurred. 
C) stabilizing selection was occurring in these species concerning larynx size. 
D) selection was acting more directly upon genotype than upon phenotype.

Question 17

Which of the following statements best summarizes evolution as it is viewed today?

Accepted Answer

A) It represents the result of selection for acquired characteristics. 
B) It is synonymous with the process of gene flow. 
C) It is the descent of humans from the present-day great apes. 
D) It is the differential survival and reproduction of the most-fit phenotypes. 
A) It represents the result of selection for acquired characteristics. 
B) It is synonymous with the process of gene flow. 
C) It is the descent of humans from the present-day great apes. 
D) It is the differential survival and reproduction of the most-fit phenotypes.

Question 18

Every HIV particle contains two RNA molecules.If two genes from one RNA molecule become detached and then,as a unit,get attached to one end of the other RNA molecule within a single HIV particle,which of these is true?

Accepted Answer

A) There are now fewer genes within the viral particle. 
B) There are now more genes within the viral particle. 
C) A point substitution mutation has occurred in the retroviral genome. 
D) One of the RNA molecules has experienced gene duplication as the result of translocation. 
A) There are now fewer genes within the viral particle. 
B) There are now more genes within the viral particle. 
C) A point substitution mutation has occurred in the retroviral genome. 
D) One of the RNA molecules has experienced gene duplication as the result of translocation.

Question 19

Sparrows with average-sized wings survive severe storms better than those with longer or shorter wings,illustrating

Accepted Answer

A) the bottleneck effect. 
B) disruptive selection. 
C) frequency-dependent selection. 
D) stabilizing selection. 
A) the bottleneck effect. 
B) disruptive selection. 
C) frequency-dependent selection. 
D) stabilizing selection.

Question 20

How did Mendel's model of inheritance help explain Darwin's theory of natural selection?

Accepted Answer

A) by observations of individuals' differences in traits 
B) by proposing a mechanism of how organisms could transmit discrete,heritable units to offspring 
C) by explaining the natural selection of genetic differences among offspring 
D) by leading to an evolutionary change 
A) by observations of individuals' differences in traits 
B) by proposing a mechanism of how organisms could transmit discrete,heritable units to offspring 
C) by explaining the natural selection of genetic differences among offspring 
D) by leading to an evolutionary change

Exam 21: The Evolution of Populations

In a population of 200 mice,brown fur is dominant to gray fur.If 120 of the 200 mice have brown fur,what is the frequency of mice that are heterozygous?

Which of the following consistently improves the degree to which organisms are well suited for life in their environment?

What is the Hardy-Weinberg equation?

Which process in sexual reproduction results in diversity at the nucleotide level?

In the formula for determining a population's genotype frequencies,the pq in the term 2pq is necessary because

The frequency of a disease is 30/1000.This is a disease that follows a dominant/recessive pattern of inheritance on one gene (where the only affected individuals are all homozygous recessive).What is the frequency of the disease genotype q2?

What is true of natural selection?

How can genetic variation at the whole gene level (gene variability)be quantified?

Which of the following is most likely to produce an African butterfly species in the wild whose members have one pattern?

Please use the following information to answer the question(s)below. -Examining the figure,which type of selection eliminates extreme frequency of individuals' phenotype?

In the formula for determining a population's genotype frequencies,the 2 in the term 2pq is necessary because

Which of the following statements best summarizes evolution as it is viewed today?

Every HIV particle contains two RNA molecules.If two genes from one RNA molecule become detached and then,as a unit,get attached to one end of the other RNA molecule within a single HIV particle,which of these is true?

Sparrows with average-sized wings survive severe storms better than those with longer or shorter wings,illustrating

How did Mendel's model of inheritance help explain Darwin's theory of natural selection?

Introduction: Evolution and the Foundations of Biology

The Chemical Context of Life

Carbon and the Molecular Diversity of Life

A Tour of the Cell

Membrane Transport and Cell Signaling

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

Gene Expression: From Gene to Protein

Regulation of Gene Expression

Development,stem Cells,and Cancer

Viruses

Genomes and Their Evolution

Descent With Modification

Phylogeny

The Origin of Species

Broad Patterns of Evolution

Early Life and the Diversification of Prokaryotes

The Origin and Diversification of Eukaryotes

The Colonization of Land by Plants and Fungi

The Rise of Animal Diversity

Plant Structure and Growth

Resource Acquisition,nutrition,and Transport in Vascular Plants

Reproduction and Domestication of Flowering Plants

Plant Responses to Internal and External Signals

Homeostasis and Endocrine Signaling

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Reproduction and Development

Neurons,synapses,and Signaling

Nervous and Sensory Systems

Motor Mechanisms and Behavior

Population Ecology and the Distribution of Organisms

Ecological Communities

Ecosystems and Energy

Conservation Biology and Global Change

Filters

The frequency of a disease is 30/1000.This is a disease that follows a dominant/recessive pattern of inheritance on one gene (where the only affected individuals are all homozygous recessive).What is the frequency of the disease genotype q²?