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