Question 1

The table shows the amino acid sequences for an eight-residue section of a small protein for five different species (1-5).  Which species differs from species 1 because of an amino acid insertion?

Accepted Answer

Species 2 shows an a...

Question 2

Which genes would most likely experience biased gene conversion?

Accepted Answer

A)   rRNA genes
B)   Globin genes
C)   Pseudogenes
D)   Genes for lysozymes
E)   Genes that are diverging in functionF) None of the above
G) B) and C)

Question 3

Which scenario would tend to make obtaining correct sequence alignments difficult?

Accepted Answer

A)   Comparing closely related species
B)   Examining slowly-evolving sequences
C)   Working with a segment of DNA in which deletions frequently evolve
D)   Knowing which types of substitutions are most likely to evolve
E)   Having sequences of a gene from several species at different degrees of evolutionary relatedness from one anotherF) C) and E)
G) B) and D)

Question 4

As the amount of lateral gene transfer in a taxon increases, it becomes _______ difficult to infer relationships among lineages within the taxon and _______ to infer species boundaries.

Accepted Answer

A)   more; more difficult
B)   more; less difficult
C)   less; more difficult
D)   less; there is no effect on the ability
E)   less; less difficultF) A) and B)
G) C) and E)

Question 5

Amino acid sequences of a homologous protein found in three species of dragonflies are presented below: Dragonfly 1: Met-Gln-Leu-Ile-Val-Arg-Ser
Dragonfly 2: Met-Gln-Leu-Ile-Val-Ser
Dragonfly 3: Met-Gln-Leu-Val-Arg-Ser
How many gaps are required to properly align these three species? (Note: Align Dragonfly 2 and Dragonfly 3 sequences with the Dragonfly 1 sequence.)

Accepted Answer

A)   Zero
B)   One
C)   Two
D)   Three
E)   FourF) B) and C)
G) A) and E)

Question 6

Below are shown segments of DNA from three species of flies.Species 1 is the common ancestor of species 2 and species 3, and we have access to its DNA because it was preserved in amber. Species 1: AACTACTGCACGCTCATA
Species 2: AACTAGTGCTCGCTCACA
Species 3: AATTACTGCACGCTCACA
There have been _______ single and _______ parallel changes as species 2 and 3 evolved from species 1.

Accepted Answer

A)   two; zero
B)   two; one
C)   three; zero
D)   three; one
E)   four; zeroF) All of the above
G) B) and C)

Question 7

_______ is most likely to lead to an increase in the rate that pseudogenes accumulate in a population.

Accepted Answer

A)   A decreased point mutation rate
B)   More intense purifying selection
C)   An increased rate of gene duplication
D)   A decreased rate of gene duplication
E)   An increase in the rate of biased gene conversionF) A) and B)
G) D) and E)

Question 8

Humans, mice, rats, chickens, and all other bony vertebrates have two groups of a developmental gene.The most likely explanation is that these two groups of genes arose from a gene duplication event in the common ancestor of

Accepted Answer

A)   humans and mice.
B)   humans and chickens.
C)   mice and rats.
D)   mice and chickens.
E)   all bony vertebrates.F) B) and D)
G) A) and E)

Question 9

Which statement about lysozymes is false?

Accepted Answer

A)   Lysozymes are only found in foregut fermenters.
B)   Lysozymes have been subjected to convergent evolution in mammals.
C)   At several amino acid positions of these enzymes, nonsynonymous substitutions have occurred faster than have synonymous substitutions in the lineage leading to foregut fermenters.
D)   The changes that have occurred in the lysozymes of foregut fermenters have made the enzymes more resistant to attack by digestive enzymes.
E)   Lysozymes digest the cell walls of bacteria.F) C) and E)
G) C) and D)

Question 10

Which statement about gene families is false?

Accepted Answer

A)   Gene families evolve via gene duplication.
B)   Pseudogenes are quickly removed from gene families by deletion.
C)   Members of a gene family can include several functional genes.
D)   Examples of gene families include the engrailed and globin gene families in vertebrates.
E)   In some gene families, the members do not evolve independently of one another.F) None of the above
G) A) and E)

Question 11

Puffer fish possess a chemical called _______ that acts as a toxin by blocking _______.

Accepted Answer

A)   tetrodotoxin; sodium channels
B)   tetrodotoxin; metabolic enzymes
C)   ligase; sodium channels
D)   ligase; metabolic enzymes
E)   engrailed; sodium channelsF) All of the above
G) None of the above

Question 12

Refer to the figure.    Which set of genes contains parologs?

Accepted Answer

A)   Chicken En1 and mouse En1
B)   Mouse En1 and human En2
C)   Human En2 and mouse En2
D)   Sea urchin En and Amphioxus En
E)   Zebrafish En2a and zebrafish En2bF) C) and D)
G) A) and B)

Question 13

Which statement about ribosomal RNA (rRNA)  genes is false?

Accepted Answer

A)   Nearly all multicellular animals have hundreds of copies of them, if not more.
B)   Within species the rRNA genes are structurally dissimilar.
C)   They evolve through concerted evolution.
D)   They do not evolve independently of one another.
E)   They are subject to biased gene conversion.F) C) and D)
G) A) and C)

Question 14

In which organism or organisms would you find the enzyme lysozyme serving a defensive role against invading bacteria?

Accepted Answer

A)   Only in foregut fermenters
B)   Only in the hoatzin
C)   Only in foregut fermenters and the hoatzin
D)   Only in mammals and a few closely related organisms
E)   In nearly all animalsF) D) and E)
G) B) and D)

Question 15

A coincident substitution occurs when

Accepted Answer

A)   a single lineage has one nucleotide change from C to A.
B)   a nucleotide changes from A to G along one lineage and from A to C along the other lineage.
C)   a nucleotide changes from A to T in two independently evolving lineages.
D)   a nucleotide changes from A to T and then to C in a single lineage.
E)   a nucleotide changes from A to C and then back to A in a single lineage.F) B) and D)
G) C) and D)

Question 16

Which statement provides the strongest evidence that most noncoding DNA is slightly deleterious?

Accepted Answer

A)   Species with larger population sizes have more noncoding DNA.
B)   Species with smaller population sizes have more noncoding DNA.
C)   Species with smaller genomes lose DNA more slowly than those with larger genomes.
D)   Species with larger genomes lose DNA more slowly than those with smaller genomes.
E)   There is an inverse relationship between the total amount of DNA in the genome and the percentage of the DNA that is noncoding.F) B) and E)
G) A) and C)

Question 17

You are a molecular evolutionist and have found five successive ancestors of today's Arctic lemming (a type of rodent)  frozen in the Arctic permafrost.You sequence the genomes of these ancestral lemmings and the modern lemming.For most genes, if you graph the number of actual substitutions on the x axis and the number of observed substitutions on the y axis, the slope of this graph will most likely

Accepted Answer

A)   be more or less constant and approximately 0.
B)   be more or less constant and approximately 1/2.
C)   be more or less constant and approximately 1.
D)   start off around 0 and increase with increasing divergence.
E)   start off around 1 and decrease with increasing divergence.F) B) and C)
G) B) and E)

Question 18

Below are short fragments of DNA sequences from two yeast strains (A and B) , which have been diverging from each other, as well as a short fragment from their common ancestor (C) . Yeast A: TGACTGCAAACATCCTAG
Yeast B: TGCCTGGACACATCGAAG
Yeast C: TGCCTGGAAACCTCCTAG
What type of information would best allow you to detect whether back substitutions occurred at any of the 18 nucleotides of the sequence as strain A evolved from the common ancestor?

Accepted Answer

A)   Additional sequences from strain A from regions near the 18 nucleotides
B)   Additional sequences from the ancestor from regions near the 18 nucleotides
C)   Phenotypic data from strain A and the ancestor
D)   The 18 nucleotides from yeast samples taken at various times between the ancestor and contemporary strain A
E)   Sequence data from closely related strainsF) B) and D)
G) B) and E)

Question 19

The sea snake is resistant to poisoning by the puffer fish sodium channel toxin tetrodoxin (TTX) .To determine which regions of the sea snake sodium channel confer resistance, a researcher can _______ the sea snake sodium channel genes.

Accepted Answer

A)   map the missense mutations of
B)   compare the rates of synonymous and nonsynonymous nucleotide substitutions within
C)   determine the rate of genetic drift within
D)   quantify the number of gene duplications within
E)   map the sequence deletions withinF) A) and D)
G) B) and D)

Question 20

Which statement about noncoding DNA is false?

Accepted Answer

A)   Noncoding DNA makes up most of the genome in bacteria and yeast.
B)   Differences in genome size among closely related species are often due to how much noncoding DNA they have.
C)   Some noncoding DNA may have a function.
D)   Species vary in the rate at which they lose noncoding DNA.
E)   Noncoding DNA includes "orphaned" long terminal repeats (LTRs) .F) All of the above
G) A) and B)

Exam 23: Evolution of Genes and Genomes

Which statement about ribosomal RNA (rRNA) genes is false?

Correct Answer
verified

_______ is most likely to lead to an increase in the rate that pseudogenes accumulate in a population.

Correct Answer
verified

In which organism or organisms would you find the enzyme lysozyme serving a defensive role against invading bacteria?

Correct Answer
verified

As the amount of lateral gene transfer in a taxon increases, it becomes _ difficult to infer relationships among lineages within the taxon and _ to infer species boundaries.

Correct Answer
verified

Correct Answer
verified

The sea snake is resistant to poisoning by the puffer fish sodium channel toxin tetrodoxin (TTX) .To determine which regions of the sea snake sodium channel confer resistance, a researcher can _______ the sea snake sodium channel genes.

Correct Answer
verified

Puffer fish possess a chemical called _ that acts as a toxin by blocking _.

Correct Answer
verified

Which genes would most likely experience biased gene conversion?

Correct Answer
verified

The table shows the amino acid sequences for an eight-residue section of a small protein for five different species (1-5). Which species differs from species 1 because of an amino acid insertion?

Correct Answer
verified
Species 2 shows an a...
View Answer

Which statement about noncoding DNA is false?

Correct Answer
verified

Refer to the figure. Which set of genes contains parologs?

Correct Answer
verified

Which statement about lysozymes is false?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Which statement provides the strongest evidence that most noncoding DNA is slightly deleterious?

Correct Answer
verified

Which statement about gene families is false?

Correct Answer
verified

Which scenario would tend to make obtaining correct sequence alignments difficult?

Correct Answer
verified

Humans, mice, rats, chickens, and all other bony vertebrates have two groups of a developmental gene.The most likely explanation is that these two groups of genes arose from a gene duplication event in the common ancestor of

Correct Answer
verified

Correct Answer
verified

A coincident substitution occurs when

Correct Answer
verified

Exam 23: Evolution of Genes and Genomes

Which statement about ribosomal RNA (rRNA) genes is false?

Correct AnswerverifiedShow Answer

_______ is most likely to lead to an increase in the rate that pseudogenes accumulate in a population.

Correct AnswerverifiedShow Answer

In which organism or organisms would you find the enzyme lysozyme serving a defensive role against invading bacteria?

Correct AnswerverifiedShow Answer

As the amount of lateral gene transfer in a taxon increases, it becomes _______ difficult to infer relationships among lineages within the taxon and _______ to infer species boundaries.

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

The sea snake is resistant to poisoning by the puffer fish sodium channel toxin tetrodoxin (TTX) .To determine which regions of the sea snake sodium channel confer resistance, a researcher can _______ the sea snake sodium channel genes.

Correct AnswerverifiedShow Answer

Puffer fish possess a chemical called _______ that acts as a toxin by blocking _______.

Correct AnswerverifiedShow Answer

Which genes would most likely experience biased gene conversion?

Correct AnswerverifiedShow Answer

The table shows the amino acid sequences for an eight-residue section of a small protein for five different species (1-5). Which species differs from species 1 because of an amino acid insertion?

Correct AnswerverifiedSpecies 2 shows an a...View AnswerShow Answer

Which statement about noncoding DNA is false?

Correct AnswerverifiedShow Answer

Refer to the figure. Which set of genes contains parologs?

Correct AnswerverifiedShow Answer

Which statement about lysozymes is false?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Which statement provides the strongest evidence that most noncoding DNA is slightly deleterious?

Correct AnswerverifiedShow Answer

Which statement about gene families is false?

Correct AnswerverifiedShow Answer

Which scenario would tend to make obtaining correct sequence alignments difficult?

Correct AnswerverifiedShow Answer

Humans, mice, rats, chickens, and all other bony vertebrates have two groups of a developmental gene.The most likely explanation is that these two groups of genes arose from a gene duplication event in the common ancestor of

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

A coincident substitution occurs when

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

As the amount of lateral gene transfer in a taxon increases, it becomes _ difficult to infer relationships among lineages within the taxon and _ to infer species boundaries.

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Puffer fish possess a chemical called _ that acts as a toxin by blocking _.

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
Species 2 shows an a...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
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Correct Answer
verified

Correct Answer
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