Question 1
Question
The first step in the polymerase chain reaction (PCR) is
Answer
-
Denaturation
-
Cooling
-
Annealing
-
Primer extension
Question 2
Question
In a polymerase chain reaction, a synthetic sequence of nucleotides are involved in
Answer
-
Denaturing
-
Heating
-
Cooling
-
Copying
-
All of the above
Question 3
Question
Bacteria protect themselves from viruses by fragmenting viral DNA upon entry with
Answer
-
Ligases
-
Endonucleases
-
Methylases
-
Vectors
-
Probes
Question 4
Question
When "sticky ends" are paired, they can be joined by
Answer
-
Restriction Enzymes
-
pSC101
-
Methylases
-
X-gal
-
DNA ligase
Question 5
Question
One of the most useful methods for identifying a specific gene is
Question 6
Question
The Polymerase Chain Reaction is used to:
Question 7
Question
When tryptophan is present in the medium, the transcription of tryptophan producing genes in E. coli is stopped by a helix-turn-helix regulator binding to the
Answer
-
trp repressor
-
trp operon
-
trp promoter
-
trp operator
-
trp polymerase
Question 8
Question
When tryptophan is present in the environment of E. coli, the tryptophan binds to the
Answer
-
trp operon
-
trp promoter
-
trp operator
-
trp repressor
-
trp polymerase
Question 9
Question
The operon that controls tryptophan producing genes in E. coli consists of _______________
Answer
-
activator
-
regulator
-
promoter
-
operator
-
repressor
Question 10
Question
In order for a gene to be transcribed, RNA polymerase must have access to the DNA helix and be able to bind to the genes
Answer
-
activator
-
regulator
-
promoter
-
operator
-
repressor
Question 11
Question
In the function of the lac operon in E. coli, the lac genes are transcribed in the presence of lactose because
Answer
-
RNA polymerase binds to the operator
-
the repressor cannot bind to the promoter
-
an isomer of lactose binds to the repressor
-
CAP does not bind to the operator
-
of the absence of cAMP
Question 12
Question
The role of methylation of DNA is now viewed as
Answer
-
interfering with DNA transcription by blocking base pairing between cytosine and guanine
-
complexing with enhancers to prevent transcription
-
prevention of mutation
-
insuring that genes that are turned off, stay off
-
irrelevant to gene transcription
Question 13
Question
E. coli is able to use foods other than glucose in the absence of available glucose, because falling levels of glucose cause an increase of
Answer
-
cAMP
-
CAP
-
lactase
-
glu operon
-
tRNA
Question 14
Question
In the absence of glucose, E. coli can import lactose to change into glucose and galactose because CAP binds to the
Answer
-
cAMP
-
DNA
-
lac operon
-
operator
-
repressor
Question 15
Question
Which is not part of the lac operon?
Answer
-
repressor
-
activator protein
-
operator
-
promoter
-
structural gene
Question 16
Question
In an operon the location of the regulatory region occurs ________ the structural genes.
Question 17
Question
Which of the following is part of an operon?
Answer
-
structural genes
-
operator
-
promoter
-
a CAP binding site
-
all of the above
Question 18
Question
Transcription is initiated when RNA polymerase binds to
Answer
-
promoter
-
initiator
-
codon
-
transcriptor
Question 19
Question
In eukaryotes, there are _______________ codons that specify amino acids
Question 20
Question
In eukaryotes, the "start" codon also specifies the amino acid,
Answer
-
phenylalanine
-
valine
-
methionine
-
aspartate
Question 21
Question
In transcription, the nucleotide sequence CAT in DNA would specify _______________ in mRNA.
Question 22
Question
The genetic code consists of groups of three nucleotides called
Answer
-
codons
-
introns
-
anticodons
-
reading frame
-
triplets
Question 23
Question
The function of tRNA is to
Answer
-
provide a site for polypeptide synthesis
-
transport amino acids to the ribosome
-
travel to the ribosome to direct the assembly of polypeptides
-
transcribe DNA
-
translate DNA
Question 24
Question
In the formation of an initiation complex, a _______________ is positioned first.
Answer
-
met-tRNA
-
ser-tRNA
-
tyr-rRNA
-
mval-tRNA
-
cyst-tRNA
Question 25
Question
The function of mRNA is to
Answer
-
provide a site for polypeptide synthesis
-
transport amino acids to the ribosome
-
travel to the ribosome to direct the assembly of polypeptides
-
transcribe DNA
-
translate DNA
Question 26
Question
The process of _______________ cuts introns from the primary transcript and the final "processed" mRNA is produced.
Answer
-
RNA cleaving
-
RNA translocation
-
RNA splicing
-
RNA elongation
-
RNA releasing
Question 27
Question
In the process of translation,
Answer
-
a strand of mRNA is formed with nucleotide sequences complementary to those of DNA
-
nucleotide sequences of tRNA are established
-
a polypeptide is formed in response to the rRNA nucleotide sequence
-
rRNA is synthesized with sequences complementary to those of tRNA
-
a polypeptide is formed as dictated by the nucleotide sequence in mRNA
Question 28
Question
In mRNA, the series of nucleotides CCC specifies
Answer
-
serine
-
proline
-
alanine
-
arginine
-
stop
Question 29
Question
A molecule of tRNA with the anticodon AAA will transport the amino acid
Answer
-
phenylalanine
-
lysine
-
glycine
-
leucine
-
alanine
Question 30
Question
As polypeptides are formed at the ribosome, elongation continues until _______________ is exposed.
Answer
-
a release factor
-
an intron
-
a nonsense codon
-
an exon
-
polypeptidases
Question 31
Question
Which one of the following is not a kind of RNA?
Question 32
Question
The direct result of transcription is
Answer
-
a duplicate DNA molecule
-
nRNA
-
protein
-
mRNA
-
none of the above
Question 33
Question
The direct result of translation is
Answer
-
duplicate DNA
-
mRNA
-
protein
-
nRNA (nuclear RNA)
-
none of the above
Question 34
Question
Which one of the following is not associated with transcription?
Answer
-
tRNA
-
mRNA
-
nRNA
-
rRNA
-
all of the above
Question 35
Question
Which one of the following is not associated with translation?
Question 36
Question
According to Chargaff's rule, the following proportion exists in DNA
Question 37
Question
The actual synthesis of DNA in E. coli is the function of
Answer
-
polymerase I
-
primase
-
primer
-
polymerase III
-
ligase
Question 38
Question
Since the first nucleotides cannot be linked in a newly synthesized strand in DNA replication, ___________ is required.
Answer
-
DNA primer
-
DNA ligase
-
DNA polymerase
-
RNA primer
-
helicase
Question 39
Question
The fact that some viruses use DNA to direct their heredity was demonstrated by
Answer
-
finding radioactive sulfur from a bacteriophage in a bacterium
-
finding radioactive phosphorus from a bacterium in a bacteriophage
-
finding that radioactive phosphorus from a bacteriophage had mutated in bacterium
-
finding radioactive phosphorus from a bacteriophage in a bacterium
-
finding radioactive sulfur from a bacterium in a bacteriophage
Question 40
Question
Okazaki fragments are used to elongate
Answer
-
the leading strand toward the replication fork
-
the lagging strand toward the replication fork
-
both strands in both directions
-
the leading strand away from the replication fork
-
the lagging strand away from the replication fork
Question 41
Question
In nucleic acids, the free hydroxyl group is attached to the _______________ carbon of the sugar.
Question 42
Question
A single enzyme is specified by a single
Answer
-
gene
-
chromosome
-
nucleosome
-
nucleotide
-
histone
Question 43
Question
In replication of DNA, the helix is opened and untwisted by
Answer
-
ribase
-
primase
-
deoxase
-
helicase
-
ligase
Question 44
Question
_______________ join DNA fragments to the lagging strand
Answer
-
telomeres
-
centromeres
-
helicases
-
ligases
-
polymerases
Question 45
Question
Which statement about the elongation of the lagging strand during DNA replication is correct?
Answer
-
It is synthesized in a 3' --> 5' direction.
-
It progresses (grows) toward the replication fork
-
It requires a short RNA primer to proceed.
-
It is synthesized by DNA ligase
-
It is synthesized continuously
Question 46
Question
If one side of a DNA molecule contains the following sequence of nucleotides, AGTCCG, the complementary sequence on the other side would be:
Answer
-
GCCTGA
-
AGTCCG
-
TCAGGC
-
CTGAAT
-
none of the above
Question 47
Question
During your summer job at Virotech, you isolate a previously unknown virus. Analysis of its genome reveals that it is composed of a double stranded DNA molecule containing 14% T (thymine). Based on this information, what would you predict the %C (cytosine) to be?
Answer
-
14%
-
28%
-
36%
-
72%
-
can't tell!
Question 48
Question
The process of acquiring a gene from another organism is called transformation.
Question 49
Question
The Hershey-Chase experiment showed that the virus protein is responsible for directing the production of new viruses.
Question 50
Question
The two sides of the double helix structure of DNA are held together with hydrogen bonds.
Question 51
Question
DNA replication is called semiconservative because half of each of the two new strands of DNA is "old" DNA from the original DNA molecule and half is "new" DNA.
Question 52
Question
Genetic engineering has been used to do all of the following except:
Answer
-
make plants more resistant to frost
-
make plants more resistant to disease
-
make plants more resistant to herbicides
-
improve the nutritional balance of plants
-
all of the above
Question 53
Question
According to Mendel, which of the following cause an organism's size, colour and markings?
Answer
-
Chromosomes
-
Genes
-
Alleles
-
Factors
Question 54
Question
Which term is associated with eukaryotic DNA?
Answer
-
chrosome
-
histone
-
telomere
-
all of the above
Question 55
Question
If 28% of a segment of DNA is composed of guanine, how much of the segment is adenine?
Question 56
Question
How did the work of Franklin and Wilkins contribute to the discovery of the structure of DNA?
Answer
-
They determined the rule of base pairing
-
They determined that DNA has an X shape
-
They determined the double helix structure
-
They determined that the strands run antiparallel
Question 57
Question
Which of these findings made Watson and Crick confident that their DNA model was correct?
Answer
-
Chargaff's base-pairing ratios
-
Pauling's three-strand model
-
Franklin's early disagreement with the double helix theory
-
All of the above
Question 58
Question
What would have been the results of Meselson and Stahl's experiment if DNA had undergone conservative replication?
Answer
-
one band containing only 14N
-
one band containing only 15N
-
two bands: one of 15N and 14N
-
three bands: one of 15N, one of 14N, and one of 1:1 14N:15N
Question 59
Question
Which characteristics of the structure of DNA results in a lagging strand and a leading strand during DNA replication?
Question 60
Question
What is the function of DNA ligase in replication?
Answer
-
It initiates a replication bubble
-
It prevents DNA strands from tangling
-
It places nucleotides to form a new DNA strand
-
It fills gaps on the lagging strand
Question 61
Question
Which method do prokaryotes use to compact DNA?
Question 62
Question
Where are telomeres located?
Answer
-
At ends of chromosomes
-
On the leading strand
-
At the replication fork
-
On prokaryotic plasmids
Question 63
Question
What is the name of Beadle and Tatum's original hypothesis?
Answer
-
One gene-one sequence hypothesis
-
One gene-one enzyme hypothesis
-
One gene-one peptide hypothesis
-
One gene-one polypeptide hypothesis
Question 64
Question
What is the sequence of information transfer, as outlined by the central dogma?
Answer
-
DNA -> tRNA -> mRNA --> polypeptide
-
DNA -> mRNA -> tRNA --> polypeptide
-
DNA -> mRNA -> rRNA --> polypeptide
-
DNA -> rRNA -> tRNA --> polypeptide
Question 65
Question
Where is the TATA box found?
Answer
-
In the termination sequence that stops DNA polymerase
-
In the termination sequence that stops RNA polymerase
-
In the promoter that enables the binding of DNA polymerase
-
In the promoter that enables the binding of RNA polymerase
Question 66
Question
What happens during capping and tailing?
Answer
-
A methyl 5' tail and poly(A) cap are added
-
A methyl 3' tail and poly(A) cap are added
-
A methyl 5' cap and poly(A) tail are added
-
A methyl 3' cap and poly(A) tail are added
Question 67
Question
How is the lac operon inhibited?
Answer
-
The lac repressor is not synthesized by the lacl gene
-
RNA polymerase is inhibited by high concentrations of allolactase
-
The lac repressor is inhbited by high concentrations of allolactase
-
Allolactase is not present to bind with the lac repressor
Question 68
Question
Which term refers to a point mutation that results in a different amino acid in a particular position?
Answer
-
Missense mutation
-
Silent mutation
-
Nonsense mutation
-
Frameshift mutation
Question 69
Question
What is the molecular tool scientists use to cut a DNA fragment from a larger piece of DNA?
Answer
-
Restriction enzymes
-
DNA primase
-
Methylase
-
DNA ligase
Question 70
Question
After excising a DNA fragment that contains a target gene, what should a molecular biologist do?
Answer
-
Introduce a vector into a suitable organism
-
Isolate a desired gene or DNA fragment
-
Select the transformed cells
-
Insert the gene into a vector
Question 71
Question
Which chemical compound can be used to stain a completed electrophoresis gel?
Answer
-
Ethidium bromide
-
Loading dye
-
Molecular marker
-
DNA polymerase
Question 72
Question
During PCR, double-stranded DNA is separated into two single strands of DNA. What is this step called?
Answer
-
Splicing
-
Denaturation
-
Extension
-
Annealing
Question 73
Question
After 8 PCR cycles, how many target sequences have been synthesized?
Question 74
Question
How does genetic therapy differ from traditional methods of treating a disease?
Answer
-
It targets the effects of the disease
-
In some cases, it fixes the genetic code itself
-
It reverses the damage done to the body
-
It replaces the need for organ transplant