Evolutionary Analysis 5th Edition Herron Freeman – Test Bank

Evolutionary Analysis 5th Edition Herron Freeman – Test Bank

Evolutionary Analysis, 5e (Herron/Freeman)
Chapter 8 Evolution at Multiple Loci: Linkage and Sex
1) When genotypes at one locus of a chromosome are independent of genotypes at another locus
of the same chromosome, the two loci are ________.
A) in linkage equilibrium
B) in linkage disequilibrium
C) nonrandomly associated
D) None of the above.
Answer: A
Section: 8.1
Skill: Knowledge/Comprehension
2) When genotypes at one locus of a chromosome are nonrandomly associated with the
genotypes at another locus of the same chromosome, the two loci are ________.
A) in linkage equilibrium
B) in linkage disequilibrium
C) nonrandomly associated
D) None of the above.
Answer: B
Section: 8.1
Skill: Knowledge/Comprehension
3) Which of the following can produce linkage disequilibrium?
A) genetic drift
B) selection on genotypes of more than one locus
C) mixing two disparate populations, each of which is in linkage equilibrium
D) All of these choices can create linkage disequilibrium.
Answer: D
Section: 8.1
Skill: Knowledge/Comprehension
4) The creation of new combinations of alleles, as a consequence of sexual reproduction with
meiosis, is called ________.
A) genetic recombination
B) outcrossing
C) genetic drift
D) linkage disequilibrium
Answer: A
Section: 8.1
Skill: Knowledge/Comprehension
2
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5) According to the accompanying figure, we can conclude that ________.
A) the rate of decline in disequilibrium occurs more quickly with a lower rate of
recombination
B) the rate of decline in disequilibrium occurs more slowly with a lower rate of recombination
C) the rate of decline in linkage disequilibrium is inversely proportional to the rate of
recombination between them
D) None of these is an accurate statement.
Answer: B
Section: 8.1
Skill: Application/Analysis
6) An advantage to studying linkage disequilibrium is that ________.
A) it provides another tool enabling the reconstruction of the history of genes and populations
B) it provides clear evidence of speciation events
C) it can be used to identify alleles that have been recently selected by natural selection
D) Both A and C.
Answer: D
Section: 8.2
Skill: Knowledge/Comprehension
3
Copyright © 2014 Pearson Education, Inc.
7) Certain loci that are in linkage disequilibrium with alleles of interest can be used as
markers, which can then be useful in reconstructing the history of those alleles in populations.
One such marker/allele is described in your text, where the allele in question has an insertion
mutation, rendering an enzyme (glucocerebrosidase, or GBA) nonfunctional. The decay curve
for linkage disequilibrium between this marker (named D1S305) and the nonfunctional GBA
allele is shown in the accompanying figure. The orange lines show the present level of linkage
disequilibrium and the inferred number of generations elapsed since the most recent common
ancestor. Assuming an average generation time of 25 years, what is the best estimate for how
long ago the most recent common ancestor existed?
A) about 55 years ago
B) about 1375 years ago
C) about 2325 years ago
D) There is insufficient data to make this determination.
Answer: B
Section: 8.2
Skill: Application/Analysis
4
Copyright © 2014 Pearson Education, Inc.
8) Certain loci that are in linkage disequilibrium with alleles of interest can be used as
markers, which can then be useful in reconstructing the history of those alleles in populations.
One such marker/allele is described in your text, where the allele in question has an insertion
mutation, rendering an enzyme (glucocerebrosidase, or GBA) nonfunctional. The decay curve
for linkage disequilibrium between this marker (named D1S305) and the nonfunctional GBA
allele is shown in the accompanying figure. The orange lines show the present level of linkage
disequilibrium and the inferred number of generations elapsed since the most recent common
ancestor. Assuming an average generation time of 25 years, how many years total will be
required for the linkage disequilibrium reach 0.2?
A) about 55 years total
B) about 100 years total
C) about 1000 years total
D) about 2500 years total
E) There is insufficient data to make this determination.
Answer: D
Section: 8.2
Skill: Application/Analysis
9) Alleles that are relatively new to a population and have been subject to positive natural
selection are characterized by having ________.
A) high frequency and high linkage disequilibrium
B) high frequency and low linkage disequilibrium
C) low frequency and high linkage disequilibrium
D) low frequency and low linkage disequilibrium
Answer: A
Section: 8.2
Skill: Application/Analysis
5
Copyright © 2014 Pearson Education, Inc.
10) Which of the following choices is NOT a potential disadvantage to sexual reproduction?
A) Finding a mate is energetically expensive.
B) Finding a mate may increase the risk of predation.
C) Copulation may not produce offspring.
D) Sexual reproduction reduces linkage disequilibrium.
E) None of the above.
Answer: E
Section: 8.3
Skill: Application/Analysi