Question 1

When does exon shuffling occur?

Accepted Answer

A)  during splicing of DNA 
B)  during mitotic recombination 
C)  as an alternative splicing pattern in post-transcriptional processing 
D)  as an alternative cleavage or modification post-translationally 
E)  as the result of faulty DNA repair 
A)  during splicing of DNA 
B)  during mitotic recombination 
C)  as an alternative splicing pattern in post-transcriptional processing 
D)  as an alternative cleavage or modification post-translationally 
E)  as the result of faulty DNA repair

Question 2

The biggest problem with the shotgun technique is its tendency to underestimate the size of the genome. Which of the following might best account for this?

Accepted Answer

A)  skipping some of the clones to be sequenced 
B)  missing some of the overlapping regions of the clones 
C)  counting some of the overlapping regions of the clones twice 
D)  having some of the clones die during the experiment and therefore not be represented 
E)  missing some duplicated sequences 
A)  skipping some of the clones to be sequenced 
B)  missing some of the overlapping regions of the clones 
C)  counting some of the overlapping regions of the clones twice 
D)  having some of the clones die during the experiment and therefore not be represented 
E)  missing some duplicated sequences

Question 3

Use the following figure to answer the next few questions.
   
Figure 21.1 Types of DNA sequences in the human genome.
The pie chart in Figure 21.1 represents the relative frequencies of the following in the human genome:
I.repetitive DNA unrelated to transposons
II.repetitive DNA that includes transposons
III.unique noncoding DNA
IV.introns and regulatory sequences
V. exons
-Which region includes Alu elements and LI sequences?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
E)  E 
A)  A 
B)  B 
C)  C 
D)  D 
E)  E

Question 4

What is bioinformatics?

Accepted Answer

A)  a technique using 3-D images of genes in order to predict how and when they will be expressed 
B)  a method that uses very large national and international databases to access and work with sequence information 
C)  a software program available from NIH to design genes 
D)  a series of search programs that allow a student to identify who in the world is trying to sequence a given species 
E)  a procedure that uses software to order DNA sequences in a variety of comparable ways 
A)  a technique using 3-D images of genes in order to predict how and when they will be expressed 
B)  a method that uses very large national and international databases to access and work with sequence information 
C)  a software program available from NIH to design genes 
D)  a series of search programs that allow a student to identify who in the world is trying to sequence a given species 
E)  a procedure that uses software to order DNA sequences in a variety of comparable ways

Question 5

What characteristic of short tandem repeat DNA makes it useful for DNA fingerprinting?

Accepted Answer

A)  The number of repeats varies widely from person to person or animal to animal. 
B)  The sequence of DNA that is repeated varies significantly from individual to individual. 
C)  The sequence variation is acted upon differently by natural selection in different environments. 
D)  Every racial and ethnic group has inherited different short tandem repeats. 
A)  The number of repeats varies widely from person to person or animal to animal. 
B)  The sequence of DNA that is repeated varies significantly from individual to individual. 
C)  The sequence variation is acted upon differently by natural selection in different environments. 
D)  Every racial and ethnic group has inherited different short tandem repeats.

Question 6

Use the following figure to answer the next few questions.
   
Figure 21.2
Figure 21.2 shows a diagram of blocks of genes on human chromosome 16 and the locations of blocks of similar genes on four chromosomes of the mouse.
-The movement of these blocks suggests that

Accepted Answer

A)  during evolutionary time, these sequences have separated and have returned to their original positions. 
B)  DNA sequences within these blocks have become increasingly divergent. 
C)  sequences represented have duplicated at least three times. 
D)  chromosomal translocations have moved blocks of sequences to other chromosomes. 
E)  higher mammals have more convergence of gene sequences related in function. 
A)  during evolutionary time, these sequences have separated and have returned to their original positions. 
B)  DNA sequences within these blocks have become increasingly divergent. 
C)  sequences represented have duplicated at least three times. 
D)  chromosomal translocations have moved blocks of sequences to other chromosomes. 
E)  higher mammals have more convergence of gene sequences related in function.

Question 7

Homeotic genes contain a homeobox sequence that is highly conserved among very diverse species. The homeobox is the code for that domain of a protein that binds to DNA in a regulatory developmental process. Which of the following would you then expect?

Accepted Answer

A)  that homeotic genes are selectively expressed over developmental time 
B)  that a homeobox-containing gene has to be a developmental regulator 
C)  that homeoboxes cannot be expressed in nonhomeotic genes 
D)  that all organisms must have homeotic genes 
E)  that all organisms must have homeobox-containing genes 
A)  that homeotic genes are selectively expressed over developmental time 
B)  that a homeobox-containing gene has to be a developmental regulator 
C)  that homeoboxes cannot be expressed in nonhomeotic genes 
D)  that all organisms must have homeotic genes 
E)  that all organisms must have homeobox-containing genes

Question 8

Why is it unwise to try to relate an organism's complexity with its size or number of cells?

Accepted Answer

A)  A very large organism may be composed of very few cells or very few cell types. 
B)  A single-celled organism, such as a bacterium or a protist, still has to conduct all the complex life functions of a large multicellular organism. 
C)  A single-celled organism that is also eukaryotic, such as a yeast, still reproduces mitotically. 
D)  A simple organism can have a much larger genome. 
E)  A complex organism can have a very small and simple genome. 
A)  A very large organism may be composed of very few cells or very few cell types. 
B)  A single-celled organism, such as a bacterium or a protist, still has to conduct all the complex life functions of a large multicellular organism. 
C)  A single-celled organism that is also eukaryotic, such as a yeast, still reproduces mitotically. 
D)  A simple organism can have a much larger genome. 
E)  A complex organism can have a very small and simple genome.

Question 9

Barbara McClintock, who achieved fame for discovering that genes could move within genomes, had her meticulous work ignored for nearly four decades, but eventually won the Nobel Prize. Why was her work so distrusted?

Accepted Answer

A)  The work of women scientists was still not allowed to be published. 
B)  Geneticists did not want to lose their cherished notions of DNA stability. 
C)  There were too many alternative explanations for transposition. 
D)  She allowed no one else to duplicate her work. 
E)  She worked only with maize, which was considered "merely" a plant. 
A)  The work of women scientists was still not allowed to be published. 
B)  Geneticists did not want to lose their cherished notions of DNA stability. 
C)  There were too many alternative explanations for transposition. 
D)  She allowed no one else to duplicate her work. 
E)  She worked only with maize, which was considered "merely" a plant.

Question 10

For mapping studies of genomes, most of which were far along before 2000, the three-stage method was often used. Which of the following is the usual order in which the stages were performed, assuming some overlap of the three?

Accepted Answer

A)  genetic map, sequencing of fragments, physical map 
B)  linkage map, physical map, sequencing of fragments 
C)  sequencing of entire genome, physical map, genetic map 
D)  cytogenetic linkage, sequencing, physical map 
E)  physical map, linkage map, sequencing 
A)  genetic map, sequencing of fragments, physical map 
B)  linkage map, physical map, sequencing of fragments 
C)  sequencing of entire genome, physical map, genetic map 
D)  cytogenetic linkage, sequencing, physical map 
E)  physical map, linkage map, sequencing

Question 11

What is the most probable explanation for the continued presence of pseudogenes in a genome such as our own?

Accepted Answer

A)  They are genes that had a function at one time, but that have lost their function because they have been translocated to a new location. 
B)  They are genes that have accumulated mutations to such a degree that they would code for different functional products if activated. 
C)  They are duplicates or near duplicates of functional genes but cannot function because they would provide inappropriate dosage of protein products. 
D)  They are genes with significant inverted sequences. 
E)  They are genes that are not expressed, even though they have nearly identical sequences to expressed genes. 
A)  They are genes that had a function at one time, but that have lost their function because they have been translocated to a new location. 
B)  They are genes that have accumulated mutations to such a degree that they would code for different functional products if activated. 
C)  They are duplicates or near duplicates of functional genes but cannot function because they would provide inappropriate dosage of protein products. 
D)  They are genes with significant inverted sequences. 
E)  They are genes that are not expressed, even though they have nearly identical sequences to expressed genes.

Question 12

Why might the cricket genome have 11 times as many base pairs as that of Drosophila melanogaster?

Accepted Answer

A)  The two insect species evolved at very different geologic eras. 
B)  Crickets have higher gene density. 
C)  Drosophila are more complex organisms. 
D)  Crickets must have more noncoding DNA. 
E)  Crickets must make many more proteins. 
A)  The two insect species evolved at very different geologic eras. 
B)  Crickets have higher gene density. 
C)  Drosophila are more complex organisms. 
D)  Crickets must have more noncoding DNA. 
E)  Crickets must make many more proteins.

Question 13

Which of the following most correctly describes a shotgun technique for sequencing a genome?

Accepted Answer

A)  genetic mapping followed immediately by sequencing 
B)  physical mapping followed immediately by sequencing 
C)  cloning large genome fragments into very large vectors such as YACs, followed by sequencing 
D)  cloning several sizes of fragments into various size vectors, ordering the clones, and then sequencing them 
E)  cloning the whole genome directly, from one end to the other 
A)  genetic mapping followed immediately by sequencing 
B)  physical mapping followed immediately by sequencing 
C)  cloning large genome fragments into very large vectors such as YACs, followed by sequencing 
D)  cloning several sizes of fragments into various size vectors, ordering the clones, and then sequencing them 
E)  cloning the whole genome directly, from one end to the other

Question 14

Bioinformatics includes all of the following except

Accepted Answer

A)  using computer programs to align DNA sequences. 
B)  analyzing protein interactions in a species. 
C)  using molecular biology to combine DNA from two different sources in a test tube. 
D)  developing computer-based tools for genome analysis. 
E)  using mathematical tools to make sense of biological systems. 
A)  using computer programs to align DNA sequences. 
B)  analyzing protein interactions in a species. 
C)  using molecular biology to combine DNA from two different sources in a test tube. 
D)  developing computer-based tools for genome analysis. 
E)  using mathematical tools to make sense of biological systems.

Question 15

The comparison between the number of human genes and those of other animal species has led to many conclusions, including

Accepted Answer

A)  the density of the human genome is far higher than in most other animals. 
B)  the number of proteins expressed by the human genome is far more than the number of its genes. 
C)  most human DNA consists of genes for protein, tRNA, rRNA, and miRNA. 
D)  the genomes of other organisms are most significantly smaller than the human genome. 
A)  the density of the human genome is far higher than in most other animals. 
B)  the number of proteins expressed by the human genome is far more than the number of its genes. 
C)  most human DNA consists of genes for protein, tRNA, rRNA, and miRNA. 
D)  the genomes of other organisms are most significantly smaller than the human genome.

Question 16

In order to determine the probable function of a particular sequence of DNA in humans, what might be the most reasonable approach?

Accepted Answer

A)  Prepare a knockout mouse without a copy of this sequence and examine the mouse phenotype. 
B)  Genetically engineer a mouse with a copy of this sequence and examine its phenotype. 
C)  Look for a reasonably identical sequence in another species, prepare a knockout of this sequence in that species, and look for the consequences. 
D)  Prepare a genetically engineered bacterial culture with the sequence inserted and assess which new protein is synthesized. 
E)  Mate two individuals heterozygous for the normal and mutated sequences. 
A)  Prepare a knockout mouse without a copy of this sequence and examine the mouse phenotype. 
B)  Genetically engineer a mouse with a copy of this sequence and examine its phenotype. 
C)  Look for a reasonably identical sequence in another species, prepare a knockout of this sequence in that species, and look for the consequences. 
D)  Prepare a genetically engineered bacterial culture with the sequence inserted and assess which new protein is synthesized. 
E)  Mate two individuals heterozygous for the normal and mutated sequences.

Question 17

Fragments of DNA have been extracted from the remnants of extinct woolly mammoths, amplified, and sequenced. These can now be used to

Accepted Answer

A)  introduce into relatives, such as elephants, certain mammoth traits. 
B)  clone live woolly mammoths. 
C)  study the relationships among woolly mammoths and other wool-producers. 
D)  understand the evolutionary relationships among members of related taxa. 
E)  appreciate the reasons why mammoths went extinct. 
A)  introduce into relatives, such as elephants, certain mammoth traits. 
B)  clone live woolly mammoths. 
C)  study the relationships among woolly mammoths and other wool-producers. 
D)  understand the evolutionary relationships among members of related taxa. 
E)  appreciate the reasons why mammoths went extinct.

Question 18

What is metagenomics?

Accepted Answer

A)  genomics as applied to a species that most typifies the average phenotype of its genus 
B)  the sequence of one or two representative genes from several species 
C)  the sequencing of only the most highly conserved genes in a lineage 
D)  sequencing DNA from a group of species from the same ecosystem 
E)  genomics as applied to an entire phylum 
A)  genomics as applied to a species that most typifies the average phenotype of its genus 
B)  the sequence of one or two representative genes from several species 
C)  the sequencing of only the most highly conserved genes in a lineage 
D)  sequencing DNA from a group of species from the same ecosystem 
E)  genomics as applied to an entire phylum

Question 19

A microarray known as a GeneChip, with most now-known human protein coding sequences, has been developed to aid in the study of human cancer by first comparing two to three subsets of cancer subtypes. What kind of information might be gleaned from this GeneChip to aid in cancer prevention?

Accepted Answer

A)  information about whether or not a patient has this type of cancer prior to treatment 
B)  evidence that might suggest how best to treat a person's cancer with chemotherapy 
C)  data that could alert patients to what kind of cancer they were likely to acquire 
D)  information about which parent might have provided a patient with cancer-causing genes 
E)  information on cancer epidemiology in the United States or elsewhere 
A)  information about whether or not a patient has this type of cancer prior to treatment 
B)  evidence that might suggest how best to treat a person's cancer with chemotherapy 
C)  data that could alert patients to what kind of cancer they were likely to acquire 
D)  information about which parent might have provided a patient with cancer-causing genes 
E)  information on cancer epidemiology in the United States or elsewhere

Question 20

In comparing the genomes of humans and those of other higher primates, it is seen that humans have a large metacentric pair we call chromosome 2 among our 46 chromosomes, whereas the other primates of this group have 48 chromosomes and any pair like the human chromosome 2 pair is not present; instead, the primate groups each have two pairs of midsize acrocentric chromosomes. What is the most likely explanation?

Accepted Answer

A)  The ancestral organism had 48 chromosomes and at some point a centric fusion event occurred and provided some selective advantage. 
B)  The ancestral organism had 46 chromosomes, but primates evolved when one of the pairs broke in half. 
C)  At some point in evolution, human ancestors and primate ancestors were able to mate and produce fertile offspring, making a new species. 
D)  Chromosome breakage results in additional centromeres being made in order for meiosis to proceed successfully. 
E)  Transposable elements transferred significantly large segments of the chromosomes to new locations. 
A)  The ancestral organism had 48 chromosomes and at some point a centric fusion event occurred and provided some selective advantage. 
B)  The ancestral organism had 46 chromosomes, but primates evolved when one of the pairs broke in half. 
C)  At some point in evolution, human ancestors and primate ancestors were able to mate and produce fertile offspring, making a new species. 
D)  Chromosome breakage results in additional centromeres being made in order for meiosis to proceed successfully. 
E)  Transposable elements transferred significantly large segments of the chromosomes to new locations.

Exam 21: Genomes and Their Evolution

When does exon shuffling occur?

The biggest problem with the shotgun technique is its tendency to underestimate the size of the genome. Which of the following might best account for this?

What is bioinformatics?

What characteristic of short tandem repeat DNA makes it useful for DNA fingerprinting?

Use the following figure to answer the next few questions. Figure 21.2 Figure 21.2 shows a diagram of blocks of genes on human chromosome 16 and the locations of blocks of similar genes on four chromosomes of the mouse. -The movement of these blocks suggests that

Homeotic genes contain a homeobox sequence that is highly conserved among very diverse species. The homeobox is the code for that domain of a protein that binds to DNA in a regulatory developmental process. Which of the following would you then expect?

Why is it unwise to try to relate an organism's complexity with its size or number of cells?

Barbara McClintock, who achieved fame for discovering that genes could move within genomes, had her meticulous work ignored for nearly four decades, but eventually won the Nobel Prize. Why was her work so distrusted?

For mapping studies of genomes, most of which were far along before 2000, the three-stage method was often used. Which of the following is the usual order in which the stages were performed, assuming some overlap of the three?

What is the most probable explanation for the continued presence of pseudogenes in a genome such as our own?

Why might the cricket genome have 11 times as many base pairs as that of Drosophila melanogaster?

Which of the following most correctly describes a shotgun technique for sequencing a genome?

Bioinformatics includes all of the following except

The comparison between the number of human genes and those of other animal species has led to many conclusions, including

In order to determine the probable function of a particular sequence of DNA in humans, what might be the most reasonable approach?

Fragments of DNA have been extracted from the remnants of extinct woolly mammoths, amplified, and sequenced. These can now be used to

What is metagenomics?

A microarray known as a GeneChip, with most now-known human protein coding sequences, has been developed to aid in the study of human cancer by first comparing two to three subsets of cancer subtypes. What kind of information might be gleaned from this GeneChip to aid in cancer prevention?

Introduction: Themes in the Study of Life

The Chemical Context of Life

Water and Life

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

Cell Communication

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

From Gene to Protein

Regulation of Gene Expression

Viruses

Biotechnology

Descent with Modification: A Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonized Land

Plant Diversity II: The Evolution of Seed Plants

Fungi

An Overview of Animal Diversity

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Plant Structure, Growth, and Development

Resource Acquisition and Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons, Synapses, and Signaling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behavior

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems and Restoration Ecology

Conservation Biology and Global Change

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