Trp operon responding to tryptophan
A) Positive regulation of an inducible system
B) Negative
regulation of an inducible system
C) Positive regulation of a
repressible system
D) Negative regulation of a repressible system
D
Lac operon responding to lactose
A) Positive regulation of an inducible system
B) Negative
regulation of an inducible system
C) Positive regulation of a
repressible system
D) Negative regulation of a repressible system
B
Lac operon responding to glucose
A) Positive regulation of an inducible system
B) Negative
regulation of an inducible system
C) Positive regulation of a
repressible system
D) Negative regulation of a repressible system
C
7) Leu operon responding to leucine
A) Positive regulation of an inducible system
B) Negative
regulation of an inducible system
C) Positive regulation of a
repressible system
D) Negative regulation of a repressible system
D
Yeast genes responding to galactose
A) Positive regulation of an inducible system
B)
Negative regulation of an inducible system
C) Positive
regulation of a repressible system
D) Negative regulation of a
repressible system
A
9) Yeast genes responding to tryptophan
A) Positive regulation of an inducible system
B) Negative
regulation of an inducible system
C) Positive regulation of a
repressible system
D) Negative regulation of a repressible system
C
The major cause of allele frequency change in short term population studies
A. Cladogenesis
B. Anagenesis
C. Genetic Drift
D.
Allopatric
E. Sympatric
C
Involves changes in chromosome number
A. Cladogenesis
B. Anagenesis
C. Genetic Drift
D.
Allopatric
E. Sympatric
E
Separated populations becoming new species
A.
Cladogenesis
B. Anagenesis
C. Genetic Drift
D.
Allopatric
E. Sympatric
D
Genetic changes accumulating within a species B
A.
Cladogenesis
B. Anagenesis
C. Genetic Drift
D.
Allopatric
E. Sympatric
B
The point of speciation
A. Cladogenesis
B. Anagenesis
C. Genetic Drift
D.
Allopatric
E. Sympatric
A
20 ) The Ames test includes liver extract because
a) Ames hated
liver
b) liver absorbs substances which might be toxic to the
bacteria
c) liver metabolizes chemicals to a mutagenic form
d) this allows the testing of the affect of the chemicals on
eukaryotic DNA
C
Which of the following is true
a) Proto-oncogenes are the gas
pedal and tumor suppressor genes are the brakes
b)
Proto-oncogenes are the brakes and tumor suppressor genes are the
brakes
c) Proto-oncogenes are the gas pedal and tumor suppressor
genes are the gas pedal
d) Proto-oncogenes are the brakes and
tumor suppressor genes are the gas pedal
A
22) Linear relationship of number of mutations to evolutionary
distance
A. Horizontal Gene transfer
B. Nonsynonymous
substitutions
C. Synonymous substitutions
D. Molecular
clock
E. Phylogenetic tree
D
23) Does not change amino acid sequence
A. Horizontal Gene
transfer
B. Nonsynonymous substitutions
C. Synonymous
substitutions
D. Molecular clock
E. Phylogenetic tree
C
24) Changes amino acid sequence
A. Horizontal Gene
transfer
B. Nonsynonymous substitutions
C. Synonymous
substitutions
D. Molecular clock
E. Phylogenetic tree
B
25) Large part of a chromosome moving to a different species
A.
Horizontal Gene transfer
B. Nonsynonymous substitutions
C.
Synonymous substitutions
D. Molecular clock
E. Phylogenetic tree
A
26) Representation of evolutionary distance and common ancestry
A. Horizontal Gene transfer
B. Nonsynonymous
substitutions
C. Synonymous substitutions
D. Molecular
clock
E. Phylogenetic tree
E
28) Which of the following statements is true?
a. In the absence
of allolactose, the lac operon is constitutively transcribed.
b.
In the absence of tryptophan, the genes of the trp operon are not
expressed.
c. When a structural gene is under positive inducible
control, a mutation that eliminates the activator will cause the
structural gene to
be constitutively expressed.
d. When a
structural gene is under positive repressible elimination of the
repressor will cause the structural gene to not be expressed.
e.
An inducible gene is transcribed when a specific substrate is present.
E
30) What does an Internal Node represent on a phylogenetic
tree?
A.Evolutionary time
B. A common ancestor
C. The
point of evolution
D. Level of divergence
B
A repressor can only function in a
a) inducible system
b)
repressible system
c) negatively regulated system
d)
positively regulated system
e) all of these systems
E
Which of the following is likely to have the most serious mutational
outcome
a) frameshift
b) missense
c) silent
d)
transition
e) transversion
A
33) Why won’t the number of DNA mutations in a gene always be
proportional to evolutionary time of separation?
A.Can’t read
mutations from fossils
B.Not all living things use DNA as their
genetic material
C.Mutations aren’t related to
evolution
D.Some mutations occur less frequently since they
change amino acids
E.Mutation rates change in different environments
D
Which of the following is not a transversion?
a) A to G
b)
G to T
c) A to C
d) G to C
e) T to A
A
Operons which regulate the production of amino acids often have an
attenuator/leader sequence in addition to the operator
because:
a) Amino acids can be toxic and need to be tightly
regulated
b) The attenuator actually determines expression level,
not the operator
c) The enzymes produced by these operons would
waste resources if produced when not needed
d) Attenuators need
ribosomes to function
C
The main way that a species acquires new genes with novel functions
is:
A. Gene duplication followed by divergence
B. Vertical
gene transfer
C. Horizontal gene transfer
D.
Mutation
E. Natural selection
A
What is the major factor defining a species?
A. Similar
appearance
B. Reproductive isolation
C. Which genus it is
part of
D. Common DNA sequences
E. Survival of the fittest
B
41) Uses methylation to determine which strand to change
A
mismatch repair
B SOS response
C Tautomerization
D
Acridine Dyes
E Direct repair
A
42) outcome of multiple UV damage
A mismatch repair
B SOS
response
C Tautomerization
D Acridine Dyes
E Direct repair
B
43) Causes frameshifts
A mismatch repair
B SOS
response
C Tautomerization
D Acridine Dyes
E Direct repair
D
44) Removes specific methyl groups
A mismatch repair
B SOS response
C
Tautomerization
D Acridine Dyes
E Direct repair
E
45) Caused by the many double bonds in the nitrogenous bases
A mismatch repair
B SOS response
C
Tautomerization
D Acridine Dyes
E Direct repair
C
47) A neural cell cannot give rise to a muscle cell. This is known
as
A. totipotent cell
B. differentiation
C.
determination
D. methylation
E. brains over brawn
C
The signal for high glucose levels in a bacterial cell is
A.
high cAMP
B. low cAMP
C. high ATP
D. CAP binds to
operator
E. Repressor binding
B
A wingless fruit fly is isolated from a population after exposure of
the parental generation to EMS. Eventually the mutation is shown to
have occurred within the coding sequence of a gene that changes a
5’-GGC-3’ codon (encoding glycine) to a 5’- AGC-3’ codon (encoding
serine). Which term would not correctly describe this
mutation?
a. Transversion
b. Induced
c.
Substitution
d. Missense
e. Loss-of-function
A
3. Which of the following statements about an animal bearing a
somatic mutation is true?
a. Some but not all of the animal's
offspring will also carry the mutation.
b. All of the animal's
offspring will carry the mutation.
c. Both the animal and its
offspring will show the mutant trait.
d. The animal but not its
offspring can be affected by the mutation
e. None of the above
D
Which of the following is most likely to cause a frameshift
mutation?
a. Base analog
b. Alkylating agent
c.
Intercalating agent
d. Ionizing radiation
e. UV light
C
9. In the absence of glucose, the CAP protein binds to a DNA sequence
adjacent to the promoter of the lac operon. Binding of CAP helps RNA
polymerase to bind to the promoter and allows for a high level of
transcription of the lac operon. Regulation of the lac operon by the
CAP protein is an example of
a. negative regulation.
b.
positive regulation.
c. induction.
d. an allosteric
effect.
e. constitutive expression.
B
11) Photoreactivation repairs DNA using
A. Blue light
B.
UV light
C. ATP
D. ligase
E. Elmerʼs glue
A
Which of the following kinds of mutations is most likely to be null
loss-of-function?
a. Transition
b. Transversion
c.
Frameshift
d. Missense
C
In Burkitt lymphoma patients, despite translocation, the oncogene
c-MYC remains intact in its new location. Yet c-MYC is believed to be
responsible for the lymphoma because
a. the c-MYC DNA sequence
undergoes hypermethylation.
b. the c-MYC DNA sequence is intact
but is inverted in the new position.
c. the c-MYC gene is placed
under the control of B-cell-specific gene promoter.
d. the c-MYC
gene is placed under the control of B-cell-specific gene regulatory sequences.
D
The lac repressor functions as a tetramer and requires binding of all
four sites before it releases because:
a) Four is a lucky number
for geneticists
b) A tetramer binds the DNA better
c) A
tetramer is more accurate in finding DNA sequences
d) This
assures that lactose levels are high before the operon turns on
D
The open reading frame in the leader region of the trp operon is
deleted. The effect will be:
A. Termination of most transcripts
B. No termination of most transcripts
C. Improper
translation of the structural genes
D. Normal regulation of
transcription
E. Random regulation of transcription
A
Which element of the lac operon can act in cis or trans?
a.
Operator
b. I gene
c. Structural genes
d.
Promoter
e. CAP-binding site
B
18. Which statement about the genetic code is not true?
a.
Coding sequences are read in groups of three adjacent
nucleotides.
b. No codon normally specifies more than one amino
acid.
c. Each species of organisms has its own unique genetic
code.
d. Some amino acids are specified by more than one
codon.
e. Genetic messages are punctuated with start and stop signals.
C
In catabolite repression of the lac operon, glucose affects most
directly the
a. catabolite-activating protein
b. level of
ATP.
c. lac repressor.
d. lac operator.
e. level of cAMP.
E
Myoglobin is a protein in muscle cells that consists of a single
polypeptide. If you are concerned with interactions between amino
acids that stabilize its overall three-dimensional structure in muscle
cells, you are concerned with its _____________ structure.
a.
quaternary
b. tertiary
c. secondary
d. primary
e.
None of the above
B
A mutant E. coli strain, grown under conditions that normally induce
the lac operon, does not produce ß-galactosidase. What is a possible
genotype of the cells?
a. lacI+ lacP+ lacO+ lacZ+ lacY–
lacA+
b. lacI+ lacP+ lacOc lacZ+ lacY+ lacA+
c. lacl+ lacP+
lacO+ lacZ+ lacY+ lacA+
d. lacI+ lacP– lacO+ lacZ+ lacY+ lacA+
D
Which event is not normally associated with development of
cancer?
a. Inactivation of a tumor-suppressor gene in a
cell
b. Inactivation of a proto-oncogene in a cell
c.
Infection of a cell with a virus that carries an oncogene
d.
Chromosome rearrangements including insertions and deletions
e.
Activation of genes encoding telomerase in somatic cells
.
B
28. Control of the E. coli lac operon by lac I is most accurately
described as
a. negative inducible.
b. negative
repressible.
c. positive inducible.
d. positive repressible
A
An operon is controlled by a repressor. When the repressor binds to a
small molecule, it binds to DNA near the operon. The operon is
constitutively expressed if a mutation prevents the repressor from
binding to the small molecule. Control of this operon is
a.
negative inducible.
b. negative repressible.
c. positive
inducible.
d. positive repressible
B
33. transversion
a. pyrimidine dimers
b.
nucleotide-excision repair
c. A•T--> G•C
d.
dominant
e. A•T --> C•G
E
34. xeroderma pigmentosum
a. pyrimidine dimers
b.
nucleotide-excision repair
c. A•T--> G•C
d.
dominant
e. A•T --> C•G
B
35. gain-of-function mutant
a. pyrimidine dimers
b.
nucleotide-excision repair
c. A•T--> G•C
d.
dominant
e. A•T --> C•G
D
36. ultraviolet light
a. pyrimidine dimers
b.
nucleotide-excision repair
c. A•T--> G•C
d.
dominant
e. A•T --> C•G
A
37. transition a. pyrimidine dimers
b. nucleotide-excision
repair
c. A•T--> G•C
d. dominant
e. A•T --> C•G
C
2) Which feature of gene regulation is present only in prokaryotic
genomes?
A. Gene dosage
B. Activators
C.
Enhancers
D. Alternative splicing
E. Attenuators
E
8) The corepressor of tryptophan biosynthesis is
A.
tRNATrp
B. Tryptophan
C. Tryptophanase
D. Tryptophan
attenuator
E. None of the above
B
What is a silent mutation?
a) A change that adds or deletes a
base from a codon
b) A change causing the protein to start in the
wrong place
c) A change from an amino acid codon to a stop
codon
d) A change in a degenerate codon position that doesn't
change the meaning of the codon
e) A change from a codon for one
amino acid to a codon for another amino acid
D
Which of the following crosses will result in hybrid
dysgenesis?
a) P- male X P- female
b) P+ male X P+
female
c) P+ male X P- female
d) P- male X P+ female
C
In the presence of lactose and glucose, which of the following
bacteria will not produce high levels of lacZ
A. I+O+Z+
B.
I+OCZ+
C. ISO+Z+
D. I-O+Z+
E. None will produce lacZ
E
Approximately how big would the average fragment size be following
digestion with a restriction enzyme that recognizes a 6 base pair
sequence?
a) 500 bp
b) 1000 bp
c) 2500 bp
d) 4000
bp
e) 6000 bp
D
Which factor binds to the TATA box in eukaryotic Pol II
promoters
A. TFIA
B. TFIID
C. TFIIID
D.
TFIB
E. TFIIIB
B
ddNTP is missing the hydroxyl at the
a) 5’ and 3’
position
b) 1’ and 2’ position
c) 2’ and 3’ position
d)
2’ and 5’ position
e) 4’ and 5’ position
C
40) Insertion sequences (IS) inserted in the genome are flanked
by:
a) Inverted genomic repeats and Inverted sequence
elements
b) Direct genomic repeats and Direct sequence
elements
c) Inverted genomic repeats and Direct sequence
elements
d) Direct genomic repeats and inverted sequence elements
D
You perform interrupted-mating experiments on three Hfr strains (A,
B, and C). Genes are transferred (from last to first) in the following
order from each strain: strain A, thi-his-gal-lac-pro; strain B,
lac-gal-his-thi-thr; strain C, azi-leu-thr-thi-his. How are the F
factors in these strains oriented?
a. A and B are oriented in the
same direction.
b. B and C are oriented in the same
direction.
c. A and C are oriented in the same direction.
d. All of them are oriented in the same direction.
C
A bacterium of genotype a+b+c+d+ is the donor in a cotransformation
mapping. The recipient is a–b–c–d–. Data from the transformed cells
are shown below. What is the order of the genes?
a+ and d+
2
d+ and c+ 0
b+ and d+ 5
a+ and c+ 5
b+ and a+
0
c+ and b+ 0
a. a c b d
b. a d c b
c. c b a
d
d. c a d b
D
A co-transduction experiment is carried out to map genes A, B and C
in E. coli. Out of 10 million phage lambda tested, 250 cotransduced A
and C, 25 cotransduced B and C and none cotransduced A and B. This
indicates that:
A. All three are on different chromosomes
B.
A and B are on different chromosomes
C. B and C are the closest
markers
D. A and B are the closest markers
E. C is the
middle marker
E
The response of the yeast Gal4 (galactose) gene to galactose is an
example of
A. an inducible system with negative
regulation
B. a repressible sytem with negative
regulation
C. an inducible system with positive
regulation
D. a repressible sytem with positive regulation
C
A wingless fruit fly is isolated from a population after exposure of
the parental generation to EMS. Eventually the mutation is shown to
have occurred within the coding sequence of a gene that changes a
5’-GGC-3’ codon (encoding glycine) to a 5’-GGG-3’ codon (encoding
glycine). Which term would not correctly describe this
mutation?
a. Transversion
b. Induced
c.
Substitution
d. Missense
e. Loss-of-function
D
The signal for high glucose levels in a bacterial cell is
A.
high cAMP
B. low cAMP
C. high ATP
D. CAP binds to
operator
E. Repressor binding
B
The genes which act as the brakes for cell growth are the
A.
proto-oncogenes
B. slow-down genes
C. oncogenes
D.
growth-halting genes
E. tumor-suppressor genes
E
The histone core consists of
A. Four polypeptides
B. Six
polypeptides
C. Eight polypeptides
D. Nine polypeptides
C
47) ras
A. Gap gene
B. cyclin
C. proto-oncogene
D. tumor
suppressor gene
E. Coordinate gene
C
49) retinablasoma gene
A. Gap gene
B. cyclin
C.
proto-oncogene
D. tumor suppressor gene
E. Coordinate gene
D
62) Determines the proper position of neuron outgrowth in mice and
humans
A. Antennaepedia
B. Hox
C.
Ultrabithorax
D. Homeotic genes
B
Operons allow coordinate regulation of genes involved in the same processes
A. Always True
B. Always False
C. Usually True
D. Usually False
C
Multigene families
A. Are always involved in immune
functions
B. Use the same promoter
C. Have the same
sequence
D. Encode protein subunits
E. Probably arose
through gene duplication
E
The majority of genes identified by genomics:
A. Are involved in
translation
B. Are involved in transcription
C. Have no
clearly identified function
D. Only make non-coding RNA
E.
Are uniformly distributed on the chromosomes
C
59) Antibody diversity is increased by
A. Break-chew-add
B.
Somatic hypermutation
C. Somatic hypomutation
D.
Somatic-Chew-Break
E. Break-chew-hypermutation
B
Two-dimension gels separate proteins based on
A. size and
size
B. hydrophobicity and size
C. hydrophobicity and
charge
D. size and color
E. charge and size
E
Relative fitness is:
A. The percentage of a given genotype found
in the next generation
B. The percentage of a given phenotype
found in the next generation
C. The number of animals that
survive in a population
D. The number of offspring an individual
with a certain genotype will produce
E. The chances of an
individual with a certain phenotype surviving for a year
A
23) Needs visible light to work
A mismatch repair
B
photoreactivation
C Tautomerization
D Acridine Dyes
E
excision repair
B
24) Causes frameshifts
A mismatch repair
B
photoreactivation
C Tautomerization
D Acridine Dyes
E
excision repair
D
25) Needs Pol I and ligase to complete the repair
A mismatch
repair
B photoreactivation
C Tautomerization
D Acridine
Dyes
E excision repair
E
26) Caused by the many double bonds in the nitrogenous bases
A mismatch repair
B photoreactivation
C
Tautomerization
D Acridine Dyes
E excision repair
C
A phage with a genome of 10,000 base pairs has a Cot 1/2 value of 5.
What is the expected Cot 1/2 of a phage with a 20,000 base pair
genome?
a) 5
b) 10
c) 2.5
d) 20
e) cannot be
determined with the information provided
B
2) Used to add restriction site to the ends of cDNAs
a) Steroid
hormone
b) linker
c) Short tandem repeats
d)
Haematopoesis
e) DAM methylase
B
3) Different numbers of these are detected in DNA
fingerprinting
a) Steroid hormone
b) linker
c) Short
tandem repeats
d) Haematopoesis
e) DAM methylase
C
4) Derived from cholesterol
a) Steroid hormone
b)
linker
c) Short tandem repeats
d) Haematopoesis
e) DAM methylase
A
5) Study of the formation of blood vessels
a) Steroid
hormone
b) linker
c) Short tandem repeats
d)
Haematopoesis
e) DAM methylase
D
6) Helps mark the old strand during DNA replication
a) Steroid hormone
b) linker
c) Short tandem
repeats
d) Haematopoesis
e) DAM methylase
E
A bacteria mutant for lacY (galactoside permease) will be:
A.
always repressed for lac operon transcription
B. constitutively
on for lac operon transcription
C. normally inducible for lac
operon transcription
D. have a lower induced response for lac
operon transcription
A
Which of the Following is true?
A. Inversions and reciprocal
translocations both interfere with recombination
B. Inversions
and reciprocal translocations both interfere with forming gametes with
the correct chromosome balance
C. Inversions interfere with
forming gametes with the correct chromosome balance, reciprocal
translocations with recombination
D. Inversions interfere with
recombination, reciprocal translocations with forming gametes with the
correct chromosome balance
D
The response of the lac operon to glucose is an example of
A. an
inducible system with negative regulation
B. a repressible sytem
with negative regulation
C. an inducible system with positive
regulation
D. a repressible sytem with positive regulation
D
26) adds a side group onto the rings of DNA bases
A xeroderma
pigmentosa
B photoreactivation
C alkylating agents
D
Acridine Dyes
E excision repair
C
27) cuts out a set number of bases of single stranded DNA
A
xeroderma pigmentosa
B photoreactivation
C alkylating
agents
D Acridine Dyes
E excision repair
E
28) increased sensitivity to UV light
A xeroderma
pigmentosa
B photoreactivation
C alkylating agents
D
Acridine Dyes
E excision repair
A
29) repairs DNA in bacteria, but not people
A xeroderma
pigmentosa
B photoreactivation
C alkylating agents
D
Acridine Dyes
E excision repair
B
30) intercalates into DNA A xeroderma pigmentosa
B
photoreactivation
C alkylating agents
D Acridine Dyes
E
excision repair
D
Which nucleotide is methylated in eukaryotic DNA to indicate a region
which should be inactivated through compression?
a) ATP
b)
CTP
c) GTP
d) TTP
B
What is a missense mutation?
a) A change that adds or deletes a
base from a codon
b) A change causing the protein to start in the
wrong place
c) A change from an amino acid codon to a stop
codon
d) A change in a degenerate codon position that doesn't
change the meaning of the codon
e) A change from a codon for one
amino acid to a codon for another amino acid
E
Pick from the following:
a. Pericentric inversions cause
dicentric and acentric chromosomes, paracentric does not
b.
Paracentric inversions cause dicentric and acentric chromosomes,
pericentric does not
c. Both Pericentric and paracentric
inversions cause dicentric and acentric chromosomes
d. Neither
Pericentric nor paracentric inversions cause dicentric and acentric chromosomes
B
Phage lambda’s decision to go lytic or lysogenic is a model
for
A. A binary developmental decision
B. Randomness of
protein binding to DNA
C. Multiple choice selection
D.
Enhancer activation of developmental pathways
E. Repressors
binding to operator sites
A
The response of the trp operon to tryptophan is an example of
a)
an inducible system with negative regulation
b) a repressible
sytem with negative regulation
c) an inducible system with
positive regulation
d) a repressible sytem with positive regulation
B
A bacterium of genotype a+b+c+d+ is the donor in a cotransformation
mapping. The recipient is a–b–c–d–. Data from the transformed cells
are shown below. What is the order of the genes?
a+ and b+
2
a+ and c+ 0
a+ and d+ 5
b+ and c+ 5
b+ and d+
0
c+ and d+ 0
a. a c b d
b. a d c b
c. c b a d
d. c a d b
C
By measuring the UV-melting curves for the DNA of two different
organisms (A and B) in the same solution and concentration, we have
found the following melting temperatures (Tm): Tm(A)= 70.2 C and
Tm(B)=75.6 C. Which of the following is correct?
a. Both DNA
molecules are equally thermally stable.
b. Both DNA molecules
have equimolar A,C,G,T
c. A has more guanine than B
d. B has
more guanine than A
D
An immunization confers future resistance because of
A.
Immunogens
B.antigens
C. junctional diversity
D.
memory cells
E. somatic hypermutation
D
B Cells get their name from
A.Bone Marrow
B. Bursa
C.
They are the second cells in the order A, B, C, etc.
D.
Best
E. Botulin
B
What is the difference between a structural gene and a regulator gene?
a. Structural genes are transcribed into mrNa, but regulator genes are not. b. Structural genes have complex structures; regulator genes have simple structures. c. Structural genes encode proteins that function in the structure of the cell; regulator genes carry out metabolic reactions. d. Structural genes encode proteins; regulator genes control the transcription of structural genes.
D
In a negative repressible operon, the regulator protein is synthesized as
a. an active activator. b. an inactive activator. c. an active repressor. d. an inactive repressor.
D
In the presence of allolactose, the lac operon repressor
a. binds to the operator. b. binds to the promoter. c. cannot bind to the operator. d. binds to the regulator gene.
C
In the trp operon, what happens to the trp repressor in the absence of tryptophan?
a. It binds to the operator and represses transcription. b. It cannot bind to the operator and transcription takes place. c. It binds to the regulator gene and represses transcription. d. It cannot bind to the regulator gene and transcription takes place.
B
Most transcriptional activator proteins affect transcription by interacting with
a. introns. b. the basal transcription apparatus. c. DNa polymerase. d. nucleosomes.
B
In rNa silencing, sirNas and mirNas usually bind to which part of the mrNa molecules that they control?
a. 5' Utr b. 5'cap c. 3' poly(a) tail d. 3'Utr
D
Which of the following changes is a transition base substitution?
A.Adenine is replaced by thymine. B.Cytosine is replaced by adenine. C.Guanine is replaced by adenine. D.three nucleotide pairs are inserted into DNA.
C
Base analogs are mutagenic because of which characteristic?
a. They produce changes in DNA polymerase that cause it to malfunction. b. They distort the structure of DNA. c. They are similar in structure to the normal bases. d. They chemically modify the normal bases.
C
Which type of mutation in telomerase can be associated with cancer cells?
A. Mutations that produce an inactive form of telomerase B.Mutations that decrease the expression of telomerase. C.Mutations that increase the expression of telomerase D. All of the above
C
Chronic myelogenous leukemia is usually associated with which type of chromosome rearrangement?
a. Duplication b. Deletion c. Inversion d. Translocation
D
Which of the following is an example of postzygotic reproductive isolation? a. Sperm of species a dies in the oviduct of species B before fertilization can take place. b. Zygotes that are hybrids between species a and B are spontaneously aborted early in development. c. the mating seasons of species a and B do not overlap. d. Males of species a are not attracted to the pheromones produced by the females of species B.
B
In general, changes in which types of sequences are expected to exhibit the slowest rates?
a. Synonymous changes in amino acid–coding regions of exons b.
Nonsynonymous changes in amino acid–coding regions of
exons c.
Changes in introns d. Changes in pseudogen
B
A gene contains a frameshift mutations. Which kind of mutagen would be capable of reversing this mutation ?
A. alkylating agent
B. base analog
C. intercalating agent
D. deaminating chemical
C
Which is NOT true of transposable elements ?
A.Many will possess short terminal inverted repeats
B.They often generate short flanking direct repeats
C.They are mobile DNA
D.Their movement will not cause mutations
D
What kind of transposition causes an increase in the copy number of transposable elements ?
A.mutagenic transposition
B.All transpositions increase copy number
C.nonreplicative transposition
D.replicative transposition
D
What kind of mutation repair does NOT involve the removing and repairing of nucleotides ?
A.nucleotide-excision repair
B.mismatch repair
C. direct repair
D.base-excision repair
C
How can spontaneous mutations arise?
A.They can occur during DNA tautomeric shifts
B. They can arise during DNA replication
C.They can arise from depurination and deamination
D.All of these can cause spontaneous mutations
D
The class of proteins known as cyclins
A.phosphorylate other cellular proteins
B.act as inhibitors of kinases
C.oscillate in concentration during the cell cycle
D.Express at a steady level throughout the cell cycle
C
In normal somatic cells, chromosomes shorten each generation. In cancer cells you notice that the chromosomes are not shortening, even after many cell divisions. A mutation in the expression of which gene might lead to this observation ?
A.DNA polymerase
B.telomerase
C. DNA-repair genes
D.retinoblastoma
B
What is the unique property of metastatic cancers?
A.They lose contact inhibition
B.They spread to other tissues
C.They usually arise from mutations
D.They grow out of control
B
Helix-turn-helix and zinc finger are structural motifs of
A.
Enhancer/promoter interaction
B. DNA binding proteins
C.
Methylation enzymes
D. Catabolic enzyme complexes
E.
Spliceosomes for primary and alternative splice sites
B
27) Which feature of gene regulation is present only in
eukaryotes?
A. Alternative splicing
B. mRNA
half-life
C. Operons
D. DNA methylation
E.
Helix-turn-helix transcriptional activators
A
15) Most tumor suppressor genes are
A. mutant
B. DNA
binding proteins
C. recessive
D. neutral in effect
E. dominant
C