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?
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
B
What is the difference between a linkage map and a physical
map?
A) For a linkage map, markers are spaced by
recombination frequency, whereas for a physical map the are spaced by
numbers of base pairs (bp).
B) For a physical map, the ATCG
order and sequence must be achieved; however, it does not for the
linkage map.
C) For a linkage map, it is shown how each gene is
linked to every other gene.
D) For a physical map, the
distances must be calculable in units such as nanometers.
E)
There is no difference between the two except in the type of
pictorial representation.
A
How is a physical map of the genome of an organism achieved?
A) using recombination frequency
B) using very high-powered
microscopy
C) using restriction enzyme cutting sites
D)
using sequencing of nucleotides
E) using DNA fingerprinting via electrophoresisC
C
Which of the following most correctly describes a 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 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
D
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?
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
E
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
D
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
C
What is bioinformatics?
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
B
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
B
Bioinformatics can be used to scan sequences for probable genes
looking for start and stop sites for transcription and for
translation, for probable splice sites, and for sequences known to be
found in other known genes. Such sequences containing these elements
are called
A) expressed sequence tags.
B)
cDNA
C) multigene families
D) proteomes
E) short tandem repeats
A
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?
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
C
What is gene annotation in bioinformatics?
A) finding
transcriptional start and stop sites, RNA splice sites, and
ESTs
B) describing the functions of protein-coding genes
C)
describing the functions of noncoding regions of the genome
D)
matching the corresponding phenotypes of different species
E)
comparing the protein sequences within a single phylum
A
Why is it unwise to try to relate an organism's
complexity with its size or number of cells?
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
B
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.
D
If humans have 2,900 Mb, a specific member of the lily family has
120,000 Mb, and a yeast has ~13 Mb, why can't this data allow us to
order their evolutionary significance?
A) Size matters
less than gene density.
B) Size does not compare to gene
density.
C) Size does not vary with gene complexity.
D)
Size is mostly due to "junk" DNA.
E) Size is
comparable only within phyla.
C
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.
C
Why might the cricket genome have 11 times as many base pairs as that
of Drosophila melanogaster?
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.
D
The comparison between the number of human genes and those of other
animal species has led to many conclusions, including
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.
B
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?
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.
B
What is the most probable explanation for the continued presence of
pseudogenes in a genome such as our own?
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
E
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.
A
Alu elements account for about 10% of the human genome. What does
this mean?
A) Alu elements cannot be transcribed into
RNA.
B) Alu elements evolved in very ancient times, before
mammalian radiation.
C) Alu elements represent the result of
transposition.
D) No Alu elements are found within individual
genes.
E) Alu elements are cDNA and therefore related to retrotransposons.
C
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
B
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?
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
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
E
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, known as hemoglobin Lepore, is known in the human
population. Hemoglobin Lepore has a deleted set of amino acids. If it
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 born with, if not
living long lives with, an anti-Lepore mutation or
duplication.
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.
B
When does exon shuffling occur?
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
C
What are genomic hot spots?
A) the locations that correspond to most genetic
diseases
B) the areas of a genome that most often mutate due to
environmental effects
C) the locations that most often correspond
with chromosomal breakpoints
D) the locations that correspond to
most genetic diseases and the locations that most often correspond
with chromosomal breakpoints
E) the locations that correspond to
most genetic diseases, the areas of a genome that most often mutate
due to environmental effects, and the locations that most often
correspond with chromosomal breakpoints
E
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
C
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
A
Which of the following studies would not likely be characterized as eco-devo?
A) the study of a particular species to see whether or not it
has developmental regulation
B) a study of the assortment of
homeotic genes in the zebra
C) a comparison of the functions of a
particular homeotic gene among four species of reptiles
D)
studying the environmental pressures on developmental stages such as
the tadpole
E) a fossil comparison of organisms from the Devonian era
C
A recent report has indicated several conclusions about comparisons
of our genome with that of Neanderthals. This report concludes, in
part, that, at some period in evolutionary history, there was an
admixture of the two genomes. This is evidenced by
A) some Neanderthal sequences not found in humans.
B) a
small 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.
B