CHAPTER 18
What is metagenomics?
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
sequencing DNA from a group of species from the same ecosystem
Which procedure is not required when the shotgun approach to
sequencing is modified as
sequencing by synthesis, in which many
small fragments are sequenced simultaneously?
A) use of
restriction enzymes
B) sequencing each fragment
C) cloning
each fragment into a plasmid
D) ordering the sequences
E)
PCR amplification
cloning each fragment into a plasmid
What is proteomics?
A) the linkage of each gene to a particular
protein
B) the study of the full protein set encoded by a
genome
C) the totality of the functional possibilities of a
single protein
D) the study of how amino acids are ordered in a
protein
E) the study of how a single gene activates many proteins
the study of the full protein set encoded by a genome
What is bioinformatics?
A) a technique using 3-D images of genes
to predict how and when they will be expressed
B) the application
of computational methods to the storage and analysis of biological
data
C) software programs available from NIH to design and
synthesize genes
D) a series of search programs that allow a
student to identify which labs around the world are
trying to
sequence the genome of a given species
E) a procedure that uses
software to order DNA sequences in a variety of comparable ways
the application of computational methods to the storage and analysis of biological data
A microarray known as a GeneChip, with most of the human
protein-coding genetic
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?
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
data that could alert patients to what kind of cancer they were likely to acquire
Which of the following most correctly describes the whole-genome
shotgun technique for
sequencing a genome?
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 fragments from many copies of an
entire chromosome, sequencing the fragments, and
then ordering
the sequences
E) cloning the whole genome directly, from one end
to the other
cloning fragments from many copies of an entire chromosome, sequencing the fragments, and then ordering the sequences
Which of the following is a representation of gene density?
A)
Humans have 2,900 Mb per genome.
B) C. elegans has ~20,000
genes.
C) Humans have ~20,000 genes in 2,900 Mb.
D) Humans
have 27,000 bp in introns.
E) Fritillaria has a genome 40 times
the size of a human genome.
Humans have ~20,000 genes in 2,900 Mb.
Why might the cricket genome have 11 times as many base pairs as that
of Drosophila
melanogaster?
A) The two insect species
evolved in 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.
Crickets must have more noncoding DNA.
The comparison between the number of human genes and those of other
animal species has
led to many conclusions, including
that
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 significantly
smaller than the human genome.
the number of proteins expressed by the human genome is far more than
the number of its
genes.
What characteristic of short tandem repeat DNA makes it useful for
DNA fingerprinting?
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.
The number of repeats varies widely from person to person or animal to animal.
In humans, the embryonic and fetal forms of hemoglobin have a higher
affinity for oxygen
than that of adults. This is due to
A)
nonidentical genes that produce different versions of globins during
development.
B) identical genes that generate many copies of the
ribosomes needed for fetal globin production.
C) pseudogenes,
which interfere with gene expression in adults.
D) the attachment
of methyl groups to cytosine following birth, which changes the type
of
hemoglobin produced.
E) histone proteins changing shape
during embryonic development.
nonidentical genes that produce different versions of globins during development.
A multigene family is composed of
A) multiple genes whose
products must be coordinately expressed.
B) genes whose sequences
are very similar and that probably arose by duplication.
C) the
many tandem repeats such as those found in centromeres and
telomeres.
D) a gene whose exons can be spliced in a number of
different ways.
E) a highly conserved gene found in a number of
different species.
genes whose sequences are very similar and that probably arose by duplication.
Which of the following can be duplicated in a genome?
A) DNA
sequences above a minimum size only
B) DNA sequences below a
minimum size only
C) entire chromosomes only
D) entire sets
of chromosomes only
E) sequences, chromosomes, or sets of chromosomes
sequences, chromosomes, or sets of chromosomes
Unequal crossing over during prophase I can result in one sister
chromosome with a deletion
and another with a duplication. A
mutated form of hemoglobin, so-called hemoglobin Lepore,
exists
in the human population. Hemoglobin Lepore has a deleted series of
amino acids. If this
mutated form was caused by unequal crossing
over, what would be an expected consequence?
A) If it is still
maintained in the human population, hemoglobin Lepore must be selected
for in
evolution.
B) There should also be persons whose
hemoglobin contains two copies of the series of amino
acids that
is deleted in hemoglobin Lepore.
C) Each of the genes in the
hemoglobin gene family must show the same deletion.
D) The
deleted gene must have undergone exon shuffling.
E) The deleted
region must be located in a different area of the individual's genome.
There should also be persons whose hemoglobin contains two copies of
the series of amino
acids that is deleted in hemoglobin Lepore.
Humans have 23 pairs of chromosomes. In contrast, chimpanzees have 24
pairs of
chromosomes and lack any pair resembling the long human
chromosome 2 pair; instead,
chimpanzees have two pairs of
medium-sized chromosomes. What is the most likely explanation
for
these differences in the human and chimpanzee genomes?
A) The
common ancestor of humans and chimpanzees had 24 pairs of chromosomes,
and at
some point in the human lineage, two chromosomes fused end
to end, providing some selective
advantage.
B) The common
ancestor of humans and chimpanzees had 23 pairs of chromosomes, but
when
chimpanzees evolved, one of the chromosomes broke in
half.
C) At some point in evolution, human ancestors and
chimpanzee ancestors were able to mate and
produce fertile
offspring, making a new species.
D) Chromosome breakage resulted
in additional centromeres being made, allowing meiosis to
proceed
successfully.
E) Transposable elements transferred significantly
large segments of the chromosomes to new
The common ancestor of humans and chimpanzees had 24 pairs of
chromosomes, and at some point in the human lineage, two chromosomes
fused end to end, providing some selective
advantage.
When does exon shuffling occur?
A) during splicing of
DNA
B) during DNA replication
C) during meiotic
recombination
D) during post-translational modification of
proteins
E) during faulty DNA repair
during meiotic recombination
In order to determine the probable function of a particular sequence
of DNA in humans, what
might be the most reasonable
approach?
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.
Look for a reasonably identical sequence in another species, prepare
a knockout of this
sequence in that species, and look for the consequences.
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?
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
that homeotic genes are selectively expressed over developmental time
A recent study compared the H. sapiens genome with that of
Neanderthals. The results of the
study indicated that there was a
mixing of the two genomes at some period in evolutionary
history.
The data that suggested this were
A) some Neanderthal sequences
not found in humans.
B) a number of modern H. sapiens with
Neanderthal sequences.
C) Neanderthal Y chromosomes preserved in
the modern population of males.
D) mitochondrial sequences common
to both groups.
a number of modern H. sapiens with Neanderthal sequences.
Fragments of DNA have been extracted from the remnants of extinct
woolly mammoths,
amplified, and sequenced. These can now be used
to
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.
understand the evolutionary relationships among members of related taxa.
Which region is occupied by exons only (V)?
A) A
B)
B
C) C
D) D
E) E
A
Which region includes Alu elements and LI sequences?
A)
A
B) B
C) C
D) D
E) E
E
The movement of these blocks suggests that
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.
chromosomal translocations have moved blocks of sequences to other chromosomes.
Which of the following represents another example of the same
phenomenon as that shown in
Figure 18.2?
A) the apparent
centric fusion between two chromosome pairs of primates such as chimps
to
form the ancestor of human chromosome 2
B) the difference
in the numbers of chromosomes in five species of one genus of
birds
C) the formation of several pseudogenes in the globin gene
family subsequent to human
divergence from other primates
D)
the high frequency of polyploidy in many species of angiosperms
the apparent centric fusion between two chromosome pairs of primates
such as chimps to
form the ancestor of human chromosome 2
How might identical and obviously duplicated gene sequences have
gotten from one
chromosome to another?
A) by normal meiotic
recombination
B) by normal mitotic recombination between sister
chromatids
C) by transcription followed by recombination
D)
by chromosomal translocation
E) by deletion followed by insertion
by chromosomal translocation
Several of the different globin genes are expressed in humans, but at
different times in
development. What mechanism could allow for
this?
A) exon shuffling
B) intron activation
C)
pseudogene activation
D) differential translation of
mRNAs
E) differential gene regulation over time
differential gene regulation over time
Bioinformatics includes all of the following except
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.
using molecular biology to combine DNA from two different sources in a test tube.
One of the characteristics of retrotransposons is that
A) they
code for an enzyme that synthesizes DNA using an RNA template.
B)
they are found only in animal cells.
C) they generally move by a
cut-and-paste mechanism.
D) they contribute a significant portion
of the genetic variability seen within a population
of
gametes.
E) their amplification is dependent on a retrovirus.
they code for an enzyme that synthesizes DNA using an RNA template.
Homeotic genes
A) encode transcription factors that control the
expression of genes responsible for specific
anatomical
structures.
B) are found only in Drosophila and other
arthropods.
C) are the only genes that contain the homeobox
domain.
D) encode proteins that form anatomical structures in the fly.
encode transcription factors that control the expression of genes
responsible for specific
anatomical structures.
Two eukaryotic proteins have one domain in common but are otherwise
very different. Which
of the following processes is most likely
to have contributed to this similarity?
A) gene
duplication
B) alternative splicing
C) exon
shuffling
D) histone modification
E) random point mutations
exon shuffling
Two eukaryotic proteins are identical except for one domain in each
protein, and these two
domains are completely different from each
other. Which of the following processes is most
likely to have
contributed to this difference?
A) gene duplication
B)
alternative splicing
C) exon shuffling
D) histone
modification
E) random point mutations
alternative splicing