Question 1

Conservation geneticists are interested in assessing the smallest sustainable population size for species of concern. Such studies are called

Accepted Answer

A)  population variation analysis. 
B)  minimum stable population analysis. 
C)  outbreeding threshold analysis. 
D)  population viability analysis. 
E)  inbreeding threshold analysis. 
A)  population variation analysis. 
B)  minimum stable population analysis. 
C)  outbreeding threshold analysis. 
D)  population viability analysis. 
E)  inbreeding threshold analysis.

Question 2

In reciprocal hybrid crosses, the heterogametic sex is typically sterile while the homogametic sex is not. This phenomenon is now called

Accepted Answer

A)  male sterility. 
B)  hybrid incompatibility. 
C)  Haldane's rule. 
D)  postzygotic isolation. 
E)  None of the above 
A)  male sterility. 
B)  hybrid incompatibility. 
C)  Haldane's rule. 
D)  postzygotic isolation. 
E)  None of the above

Question 3

Sterile offspring of hybrid matings provide an example of

Accepted Answer

A)  prezygotic isolation. 
B)  sexual selection. 
C)  postzygotic isolation. 
D)  natural selection. 
E)  heterosis. 
A)  prezygotic isolation. 
B)  sexual selection. 
C)  postzygotic isolation. 
D)  natural selection. 
E)  heterosis.

Question 4

Twenty loci are screened for genetic variation in a common caterpillar species. Four loci are found to have two or more alleles. The proportion of polymorphic loci for this population is thus

Accepted Answer

A)  0.10. 
B)  0.20. 
C)  0.30. 
D)  0.40. 
E)  0.50. 
A)  0.10. 
B)  0.20. 
C)  0.30. 
D)  0.40. 
E)  0.50.

Question 5

For two populations to remain genetically homogenized, a significant proportion of the population of each must be exchanged at least every other generation.

Accepted Answer

A) True 
 B)False

Question 6

For a gene A, a geneticist studying a population of beetles found the following genotypes: AA 45 beetles Aa 347 beetles aa 8 beetles What is the observed genotypic frequency of Aa individuals?

Accepted Answer

A)  1.15 
B)  0.02 
C)  0.13 
D)  0.90 
E)  0.86 
A)  1.15 
B)  0.02 
C)  0.13 
D)  0.90 
E)  0.86

Question 7

Why do we expect that postzygotic isolation evolutionarily precedes prezygotic isolation in the speciation process?

Accepted Answer

Postzygotic isolation is fitness-reducin

Question 8

Two closely related insect species are active at different times of day, with one diurnal and the other nocturnal. This is an example of spatial isolation.

Accepted Answer

A) True 
 B)False

Question 9

According to the Hardy-Weinberg principle, at equilibrium the allele frequencies are dependent on the genotypic frequencies.

Accepted Answer

A) True 
 B)False

Question 10

With respect to a gene with two alleles, for each generation of complete inbreeding the proportion of heterozygotes is expected to be reduced by 1/2 while the proportion of each homozygous class is expected to increase in frequency by 1/4. Explain why this is so.

Accepted Answer

The three genotypes for our two-allele g

Question 11

Populations that suffer significant reductions in number may experience two population-genetic consequences that together can hasten their decline. Which two processes are likely to act in concert in small populations, and what is their effect?

Accepted Answer

The two processes are inbreeding and dri

Question 12

Which of the following is not a form of genetic drift?

Accepted Answer

A)  Founder event 
B)  Population bottleneck 
C)  Heterozygote advantage 
D)  Nonrandom mating 
E)  All of the above are forms of genetic drift. 
A)  Founder event 
B)  Population bottleneck 
C)  Heterozygote advantage 
D)  Nonrandom mating 
E)  All of the above are forms of genetic drift.

Question 13

In the absence of gene flow, two populations are expected to

Accepted Answer

A)  change genetically in parallel fashion. 
B)  become gradually dissimilar over time. 
C)  experience different degrees of genetic drift. 
D)  experience different mutation rates. 
E)  remain identical owing to natural selection. 
A)  change genetically in parallel fashion. 
B)  become gradually dissimilar over time. 
C)  experience different degrees of genetic drift. 
D)  experience different mutation rates. 
E)  remain identical owing to natural selection.

Question 14

In light of the fact that the assumptions of the Hardy-Weinberg principle are unrealistic (no mutation, no selection, etc.), how can the principle be useful to population geneticists?

Accepted Answer

In one respect, the Hardy-Weinberg princ

Question 15

The balance model of genetic variation proposes that

Accepted Answer

A)  levels of genetic variation are determined by a balance between genetic drift and gene flow. 
B)  natural selection maintains genetic variation in populations. 
C)  most individuals in a population will be homozygous for alleles favored by natural selection. 
D)  recurrent mutation and random processes maintain variation without natural selection. 
E)  alleles that function best are strongly favored by natural selection. 
A)  levels of genetic variation are determined by a balance between genetic drift and gene flow. 
B)  natural selection maintains genetic variation in populations. 
C)  most individuals in a population will be homozygous for alleles favored by natural selection. 
D)  recurrent mutation and random processes maintain variation without natural selection. 
E)  alleles that function best are strongly favored by natural selection.

Question 16

In the Hardy-Weinberg model, the frequency of heterozygotes is represented as

Accepted Answer

A)  p2. 
B)  p. 
C)  2pq. 
D)  q. 
E)  q2. 
A)  p2. 
B)  p. 
C)  2pq. 
D)  q. 
E)  q2.

Question 17

A sizable population was analyzed for SNPs in a certain DNA region and found all four possible variants at the following frequencies: SNP 1: GGTCTAGGA; frequency = 0.91 SNP 2: GGTGTAGGA; frequency = 0.03 SNP 3: GGTATAGGA; frequency = 0.03 SNP 4: GGTTTAGGA; frequency = 0.03 What is the total frequency of heterozygotes at this SNP locus?

Accepted Answer

A)  0.009 
B)  0.0018 
C)  0.170 
D)  0.828 
E)  0.055 
A)  0.009 
B)  0.0018 
C)  0.170 
D)  0.828 
E)  0.055

Question 18

Two populations experience equally severe bottlenecks, reducing each to one-tenth their original size. One population is in the bottleneck for one generation, and the other is in the bottleneck for five generations. You assess heterozygosity of both populations after they have been restored to their prebottleneck size. What do you expect to find, and why?

Accepted Answer

The population that was bottlenecked for

Question 19

Genetic drift may lead to

Accepted Answer

A)  increased heterozygosity at many loci. 
B)  a decrease in the mutation rate of a particular gene. 
C)  loss of genetic variation in a population. 
D)  Hardy-Weinberg equilibrium. 
E)  all of the above. 
A)  increased heterozygosity at many loci. 
B)  a decrease in the mutation rate of a particular gene. 
C)  loss of genetic variation in a population. 
D)  Hardy-Weinberg equilibrium. 
E)  all of the above.

Question 20

Remote oceanic islands are characterized as having disharmonic biota, meaning the number and relative proportions of taxa living on the island differ significantly from the number and relative proportions of taxa on the nearest continental mainland area. Each island system is disharmonic in its own unique way. Why?

Accepted Answer

This pattern stems from the random natur

Exam 1: Genetics of Bacteria and Bacteriophages

Conservation geneticists are interested in assessing the smallest sustainable population size for species of concern. Such studies are called

In reciprocal hybrid crosses, the heterogametic sex is typically sterile while the homogametic sex is not. This phenomenon is now called

Sterile offspring of hybrid matings provide an example of

Twenty loci are screened for genetic variation in a common caterpillar species. Four loci are found to have two or more alleles. The proportion of polymorphic loci for this population is thus

For two populations to remain genetically homogenized, a significant proportion of the population of each must be exchanged at least every other generation.

For a gene A, a geneticist studying a population of beetles found the following genotypes: AA 45 beetles Aa 347 beetles aa 8 beetles What is the observed genotypic frequency of Aa individuals?

Why do we expect that postzygotic isolation evolutionarily precedes prezygotic isolation in the speciation process?

Two closely related insect species are active at different times of day, with one diurnal and the other nocturnal. This is an example of spatial isolation.

According to the Hardy-Weinberg principle, at equilibrium the allele frequencies are dependent on the genotypic frequencies.

With respect to a gene with two alleles, for each generation of complete inbreeding the proportion of heterozygotes is expected to be reduced by 1/2 while the proportion of each homozygous class is expected to increase in frequency by 1/4. Explain why this is so.

Populations that suffer significant reductions in number may experience two population-genetic consequences that together can hasten their decline. Which two processes are likely to act in concert in small populations, and what is their effect?

Which of the following is not a form of genetic drift?

In the absence of gene flow, two populations are expected to

In light of the fact that the assumptions of the Hardy-Weinberg principle are unrealistic (no mutation, no selection, etc.), how can the principle be useful to population geneticists?

The balance model of genetic variation proposes that

In the Hardy-Weinberg model, the frequency of heterozygotes is represented as

Genetic drift may lead to

Variations in Chromosome Structure and Number

Advanced Gene Mapping in Eukaryotes

Gene Mapping in Eukaryotes

Quantitative Genetics

Extensions of Mendelian Genetic Principles

Chromosomal Basis of Inheritance

Molecular Evolution

Population Genetics

Non-Mendelian Inheritance

Genetics of Cancer

Genetic Analysis of Development

Regulation of Gene Expression in Eukaryotes

Mendelian Genetics

Regulation of Gene Expression in Bacteria and Bacteriophages

Genomics

Applications of Recombinant DNA Technology

Recombinant DNA Technology

DNA Mutation, DNA Repair, and Transposable Elements

Gene Expression: Translation

Gene Expression: Transcription

Gene Control of Proteins

DNA Replication

DNA: The Genetic Material

Genetics: an Introduction

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