♥Quiz 4 - 2025 spring♥ Flashcards
(151 cards)
1
Q
The chain terminator on a NRTI used in HIV-I antiviral drug therapy could be?
A. 2’-H
B. 3’-H
C.5’- phosphate
D. 5’- bisphosphate
E. 3’-OH
A
3’- H
2
Q
Plant virus that does not acquire an envelope by budding is ? ———-
A. amyloid
B. TMV
C. bacteriophage
D. influenza
E. HIV-I
A
TMV
3
Q
The two methods most often used in recombinant DNA technology are — &— ?
A. proto-oncogene; tumor suppressor protein
B. RT ; protease
C. chicken pox ; shingles
D. hydrophilic surface ; hydrophobic core
E. ligation ; transformation
A
ligation ; transformation
4
Q
The product lab Proj3 is S. cerevisiae ——–?
A. vector that can accommodate 100 kb inserts
B. small molecule inhibitor of abl TK
C. replica of a protein gel probed with specific antibody
D. genomic DNA clone library
E. membrane blot of electrophoretically separated RNA probed with labeled nucleic acid
A
genomic DNA clone library
5
Q
Lysogeny leads to ___ as result of bacteriophate infection ?
A. death of host cell
B. antigenic drift
C. restrction endonclease degradation of bacteriophage DNA
D. incorporation into host chromosome
E. burst of bacteriophage progeny with lysis of host cell
A
incorporation into host chromosome
6
Q
Basic local alignment Search Tool (BLAST) is ?
A. a procedure that uses PET scan data to treat autism spectrum disorder
B. A bioinformatics tool for pairwise Query/Subject comparision of nucleotide or amino acid sequences
C. an app that allows the NSA to locate York college students using GPS technology
D. a global analysis program that allows comparison of any number of input sequence
E. a technique forusing 3-D image of cells that predicts how and when they will divide
A
A bioinformatics tool for pairwise Query/Subject comparision of nucleotide or amino acid sequences
7
Q
The minimum probe length reliable library screening is —- nt?
A. 30000
B. 15-20
C. 4
D. 4 to the 15 th power
E. 1kb, the resolution limit of sanger sequencing
A
15-20
8
Q
Which would Not be a characteristic of cDNA?
A. reverse transcriptase
B. intermediate in HIV-I infection
C. exonic sequences
D. intronic sequences
E. double stranded
A
intronic sequences
9
Q
A home COVID-19 test uses ?
A. microarray analysis
B. amniocentesis or chorionic villus biopsy
C. RT-PCR
D. antibody detection of spike protein
E. western blotting for viral DNA
A
antibody detection of spike protein
10
Q
A mail Covid-19 test uses ?
A. antibody detection of spike protein
B. western blotting for viral DNA
C. RT-PCR
D. amniocentesis or chorionic villus biopsy
E. microarray analysis
A
RT-PCR
11
Q
The foremost method for selecting recombinant plasmid transformants is ?
A. RT-PCR
B. soluthwestern blotting
C. antibiotic resistance
D. AZT resistance
E. oligonucleotide microarrays
A
anribiotic resistance
12
Q
Northern blot is a ?
A. genomic DNA library
B. cloning vector that can accommodate 100 kb inserts
C. replica of a protein gel probed with specific antibody
D. small molecule inhibitor of abl TK
E. membrane blot of electrophoretically separated RNA probed with labeled nucleic acid
A
membrane blot of electrophoretically separated RNA probed with labeled nucleic acid
13
Q
Multiple Sequence Alignment is ?
A. a procedure that uses PET scan data to treat autism spectrum disorder
B. A bioinformatics tool for pairwise Query/Subject comparision of nucleotide or amino acid sequences
C. an app that allows the NSA to locate York college students using GPS technology
D. a global analysis program that allows comparison of any number of input sequence
E. a technique forusing 3-D image of cells that predicts how and when they will divide.
A
a global analysis program that allows comparison of any number of input sequence
14
Q
Lytic infection leads to ——– of progeny virus at completion of an infection cycle?
A. burst
B. drift
C. dearth
D. explosion
E. death
A
burst
15
Q
** Many animal viruses acquire an —– by budding ?**
A. lysogen
B. Alu element
C. cell wall
D. membrnous envelope
E. mutant tumor suppressor protein
A
membrnous envelope
16
Q
Tobacco mosaic disease is caused by a —- agent than other pathogens known at the time ?
A. larger
B. more virulent smaller
C. less virulent
D. less hydrophilic
E. smaller
A
smaller
17
Q
A
18
Q
A
19
Q
A
20
Q
A
21
Q
A
22
Q
A
23
Q
What are the two reading frames of Influenza RNA?
A
PB1 Frame 1 (PB1 F1) and PB1 Frame 2 (PB1 F2)
These frames refer to different ways the viral RNA can be translated into proteins.
24
Q
What does the viral HA protein attach to on host cells?
A
Sialic acid glycosyl side chains on host cell membrane glycoproteins
This attachment is crucial for the virus to enter the host cell.
25
What is the result of a coinfection of a host cell by two different influenza virus types?
Progeny virus includes a 'hybrid' type
## Footnote
This phenomenon can lead to new strains of the virus.
26
What is antigenic shift?
Reassortment
## Footnote
This refers to the process by which different strains of viruses exchange genetic material.
27
What is quasispecies in the context of viral populations?
Genetically heterogeneous populations due to accumulated mutations
## Footnote
RNA polymerases are more error-prone than DNA polymerases, leading to this diversity.
28
What is the danger of low-dose Tamiflu?
Blocks NA, only effective early in infection
## Footnote
Tamiflu is an antiviral medication used to treat influenza.
29
What can happen when viral strains cross species barriers?
They can exchange genetic information with other viruses to which humans have no immunity
## Footnote
This can lead to new and potentially dangerous viral strains.
30
What was the 2009 flu pandemic originally called?
Swine flu
## Footnote
It was believed to have originated from pigs.
31
What are emerging viruses?
Viruses that suddenly become apparent
## Footnote
They can cause outbreaks like the H1N1 influenza virus in 2009.
32
How do vaccines work?
By stimulating the immune system to defend against pathogens
## Footnote
Vaccines are non-infectious derivatives of disease agents.
33
What is a significant challenge to vaccine development?
High variability of surface antigens
## Footnote
This variability is due to error-prone viral genome replication.
34
What type of viruses primarily infect plants?
More than 2,000 types of viral diseases of plants are known
## Footnote
Most of these viruses have RNA genomes.
35
What are viroids?
Small circular RNAs that infect plants and disrupt their growth
## Footnote
They do not code for any protein.
36
What are prions?
Slow-acting, virtually indestructible infectious proteins
## Footnote
They cause transmissible spongiform encephalopathies in mammals.
37
Fill in the blank: Viruses are not ______ organisms.
living
## Footnote
They can replicate only within cells.
38
What disease is caused by the Coconut cadang-cadang viroid?
Cadang-cadang
## Footnote
This viroid is lethal to coconut plants.
39
What is recombinant DNA?
Segments from two sources, often from different species, combined in vitro into one DNA molecule.
40
What are the two main advances that DNA sequencing relies on?
* Recombinant DNA
* Rapid methods for DNA sequencing and in vitro DNA amplification (PCR).
41
What is genetic engineering?
The manipulation of genes for practical purposes.
42
How has DNA technology impacted biotechnology?
It has revolutionized the manipulation of organisms or their genetic components to make useful products.
43
What is a microarray?
A tool that detects differences in expression of thousands of genes between normal and cancer cells in a single experiment.
44
What is DNA cloning?
A method to isolate DNA segments by making multiple copies of a gene or other DNA segment.
45
What are the characteristics of a cloning vector?
* Circular duplex DNA
* Origin of DNA replication
* Selectable marker (e.g., Amp gene)
* MCS (cluster of single cut RE sites).
46
What must a host cell be for effective DNA cloning?
* Live
* Competent for plasmid DNA uptake
* Antibiotic sensitive (e.g., AmpS).
47
What is the purpose of using antibiotics in DNA cloning?
To select for bacteria that have taken up the plasmid containing the gene of interest.
48
What are restriction enzymes?
Bacterial enzymes that cut DNA molecules at specific DNA recognition sequences called restriction sites.
49
What is directional cloning?
A method that uses a combination of different sticky end restriction enzymes to insert DNA fragments in a specific orientation.
50
True or False: Sticky ends are produced by restriction enzymes that cut DNA in a staggered fashion.
True.
51
What is a recombinant bacterium?
A bacterium that contains a recombinant plasmid with foreign DNA.
52
Fill in the blank: The process of sealing nicks in DNA strands is done by _______.
[DNA ligase]
53
What is a selectable marker in a cloning vector?
A gene that provides a way to identify cells that have taken up the vector, such as antibiotic resistance.
54
What is the role of the multiple cloning site (MCS) in a cloning vector?
It contains several restriction sites for inserting foreign DNA.
55
What is the typical result of transforming a bacterial cell with a recombinant plasmid?
The bacterial cell replicates the plasmid, producing multiple copies of the gene of interest.
56
What does the term 'transformant' refer to?
A bacterial cell that has successfully taken up a plasmid.
57
What type of DNA is typically used in gene cloning?
Plasmid DNA.
58
What is the purpose of using a spin column in plasmid extraction?
To purify plasmids from host cells.
59
What is the significance of the lacZ gene in cloning?
It is used for blue/white selection to differentiate between recombinant and non-recombinant colonies.
60
What is a cDNA library?
A collection of complementary DNA clones that represent the mRNA of a cell.
61
What is the main application of recombinant human antithrombin?
It can be purified from transgenic goats' milk and used as a drug.
62
What are the steps involved in producing clones of cells carrying recombinant plasmids?
* Isolate genomic DNA
* Use a bacterial plasmid as a cloning vector
* Cut both DNAs with the same restriction enzyme
* Ligate DNA fragments to form a recombinant plasmid.
63
What are DNA fragments?
Segments of DNA that can be cloned or manipulated
## Footnote
DNA fragments are essential for various molecular biology techniques, including cloning and sequencing.
64
Define recombinant plasmids.
Plasmids that contain DNA inserts from different sources
## Footnote
They are used in genetic engineering to introduce new genes into organisms.
65
What is a nonrecombinant plasmid?
A plasmid that does not contain foreign DNA
## Footnote
It replicates independently within the bacterial cell.
66
What is the purpose of transforming bacteria?
To introduce plasmids that can carry foreign DNA into bacterial cells
## Footnote
This process allows for the expression and replication of foreign genes.
67
What does it mean to screen for 'GOI'?
To identify the gene of interest among cloned DNA
## Footnote
Screening is crucial for isolating specific genes for further study.
68
What is the result of a transformant (AmpR) bacteria?
Bacteria that carry plasmids with antibiotic resistance
## Footnote
AmpR indicates resistance to ampicillin, allowing for selection of successfully transformed cells.
69
What indicates a colony carrying a non-recombinant plasmid?
Colony appears blue due to an intact lacZ gene
## Footnote
This colorimetric assay is used in blue/white screening to differentiate recombinant from non-recombinant plasmids.
70
What does a colony carrying a recombinant plasmid look like?
Colony appears white due to a disrupted lacZ gene
## Footnote
This is used to identify successful cloning events.
71
What is a genomic DNA library?
A collection of recombinants produced by cloning DNA fragments from an entire genome
## Footnote
It allows for the study of all genes present in an organism.
72
What is a cDNA library?
A library made by reverse transcribing cellular mRNA and cloning the resulting DNA
## Footnote
It represents the subset of genes that are expressed in a specific cell type.
73
Define a bacterial artificial chromosome (BAC).
A type of vector designed to carry a large DNA insert
## Footnote
BACs are useful in constructing genomic libraries.
74
What is nucleic acid hybridization?
A method used to identify a clone carrying the gene of interest by annealing a complementary labeled nucleic acid probe
## Footnote
This technique is crucial for locating specific sequences within complex mixtures of DNA.
75
How long should a synthetic oligonucleotide probe be?
15-20 nucleotides long for specificity
## Footnote
This length minimizes the chance of random binding to non-target sequences.
76
What is the advantage of cDNA clones over genomic clones?
cDNA clones express recombinant eukaryotic proteins better because introns are removed
## Footnote
This makes them more suitable for protein expression studies.
77
What are the components of a eukaryotic expression vector?
Contains an active promoter and a strong translation initiation site
## Footnote
Essential for efficient gene expression in eukaryotic systems.
78
What challenges exist when expressing eukaryotic genes in bacterial systems?
Technical difficulties with solubility and post-translational modifications
## Footnote
These issues can lead to improperly folded proteins.
79
What is electroporation?
A method to introduce recombinant DNA into eukaryotic cells using electrical pulses
## Footnote
This creates temporary holes in the plasma membrane for DNA uptake.
80
Define transfection.
The process by which DNA enters a cell, often facilitated by cationic liposomes
## Footnote
This method is commonly used for delivering genetic material into cells.
81
What is the significance of the Pax-6 gene?
It directs eye formation in both vertebrates and insects
## Footnote
This gene illustrates the conservation of genetic functions across species.
82
What is gel electrophoresis used for?
To analyze and compare genomes by separating nucleic acids or proteins
## Footnote
It allows researchers to visualize DNA fragments based on size.
83
What are restriction fragment length polymorphisms (RFLPs)?
DNA sequence variations that alter restriction sites
## Footnote
RFLPs can be used in genetic mapping and disease association studies.
84
How can restriction fragment analysis distinguish between alleles?
By comparing the digestion patterns of DNA fragments
## Footnote
Differences in restriction sites can indicate mutations affecting gene function.
85
What does RFLP stand for?
Restriction Fragment Length Polymorphism
86
What are RFLPs linked to in genetic research?
Disease genes for gene discovery
87
True or False: Some SNPs cause RFLPs.
True
88
What is the significance of a RFLP in relation to disease genes?
It can be linked to a disease gene or be in a coding region (causal)
89
What technique combines gel electrophoresis of DNA fragments with nucleic acid hybridization?
Southern blotting
90
What are the two efficient methods for sequencing DNA developed in the mid-1970s?
Maxam and Gilbert's method, Sanger's method
91
How does the Sanger method for DNA sequencing work?
Based on enzymatic primer extension and dideoxy nucleotide chain termination
92
What is the maximum length of DNA that can be sequenced in a single run using automated Sanger sequencing?
Up to ~1 Kb
93
Fill in the blank: The _____ method became more widely used due to its greater flexibility.
Sanger
94
What is the role of ddNTPs in DNA sequencing?
Chain terminators
95
What are the necessary ingredients for PCR?
* Template
* Primer pair
* dNTPs
* Heat-stable Taq DNA polymerase
96
Describe the three-step cycles in PCR.
* Heat denaturation
* Primer annealing
* Primer extension
97
True or False: PCR results in a population of identical DNA molecules.
True
98
What is the purpose of primers in PCR?
To bind to the target DNA sequence and initiate amplification
99
What does the term 'amplicon' refer to in PCR?
The specific DNA target being copied
100
What is the role of the enzyme Taq polymerase in PCR?
To synthesize new DNA strands
101
Fill in the blank: In PCR, each cycle yields _____ times the number of DNA molecules.
twice
102
What does Southern blotting allow researchers to do?
Identify specific DNA fragments immobilized on a membrane using labeled probes
103
What is the difference between Southern blotting and Northern blotting?
Southern blotting deals with DNA fragments, while Northern blotting deals with RNA fragments
104
What is the purpose of using fluorescently tagged ddNTPs in automated DNA sequencing?
To identify the nucleotide at the 3' end of the DNA fragment
105
How is the DNA sequence read from the resulting electropherogram?
By analyzing the length and color of the labeled strands
106
True or False: PCR can only amplify DNA, not RNA.
True
107
What is the primary technique used in the Polymerase Chain Reaction (PCR)?
Polymerase Chain Reaction (PCR)
## Footnote
PCR is a method used to amplify DNA sequences.
108
How many molecules are yielded in Cycle 1 of PCR?
2 molecules
109
How many molecules are yielded in Cycle 2 of PCR?
4 molecules
110
How many molecules are yielded in Cycle 3 of PCR?
8 molecules
111
What is the recommended length for PCR primers to ensure specificity?
15-20 nt long
112
Why is a primer length of 15-20 nt recommended?
Ensures specificity and tightness of annealing
113
What are SNPs and how often do they occur?
Single nucleotide polymorphisms (SNPs) occur on average every 1000 base pairs
114
What is the frequency of SNPs in the mitochondrial genome compared to the nuclear genome?
Approximately 10X higher
115
How can SNPs be detected?
By PCR and sequencing
116
What is Genome-Wide Association Studies (GWAS) used for?
To find genetic markers linked to diseases
117
True or False: SNPs can be genetic markers for disease-causing alleles.
True
118
What role do sequence-specific primers play in disease diagnosis?
They are used in PCR to identify disease-causing mutations
119
What does Next Generation Sequencing (NGS) reduce?
The cost of large scale sequencing
120
What technique uses nucleic acid probes to study gene expression?
In situ hybridization
121
What is Northern blotting?
A method combining gel electrophoresis of mRNA and hybridization with a probe
122
What is the advantage of Reverse transcriptase-polymerase chain reaction (RT-PCR) over Northern blotting?
Quicker, more sensitive, and requires less mRNA
123
What is synthesized during RT-PCR?
cDNA from mRNA
124
What is the purpose of using RNA interference (RNAi)?
To silence gene expression
125
What is a totipotent cell?
A cell that can generate a complete new fertile organism
126
What is the most commonly used vector for introducing new genes into plant cells?
Ti plasmid
127
What is the concern regarding genetically modified organisms (GMOs)?
Potential creation of super weeds and allergic reactions
128
What is somatic cell nuclear transfer (SCNT)?
Replacing the nucleus of an egg cell with that of a differentiated cell
129
Who was Dolly?
The first mammal cloned from an adult somatic cell
130
What is the outcome of introducing mutations into a cloned gene?
Altering or destroying its function
131
What happens to a gene when it is knocked out?
The gene's function may be determined by examining the mutant’s phenotype
132
What is the significance of using DNA microarrays?
To analyze expression patterns of thousands of genes simultaneously
133
What is the process of gene expression analysis using DNA microarrays?
Compare patterns of gene expression in different tissues or conditions
134
What is the process of removing the nucleus from an oocyte called?
Nuclear Transfer
## Footnote
This process is a key step in somatic cell nuclear transfer (SCNT).
135
What does SCNT stand for?
Somatic Cell Nuclear Transfer
## Footnote
SCNT is a technique used in cloning.
136
What is superovulation?
A hormonal treatment to induce the production of multiple oocytes
## Footnote
This technique is often used in cloning and assisted reproductive technologies.
137
What is the role of the surrogate mother in cloning?
To carry and gestate the cloned embryo
## Footnote
The surrogate mother helps in the development of the clone, such as Dolly the sheep.
138
What was significant about Dolly the sheep?
She was the first mammal cloned from an adult somatic cell
## Footnote
Dolly's cloning demonstrated that adult cells can be reprogrammed.
139
What are the common problems associated with animal cloning?
* Low success rate
* Cloned animals often exhibit defects
* Premature aging
## Footnote
These issues arise from the complexities of nuclear transplantation.
140
What is transgenesis?
The process of introducing genes from one species into another
## Footnote
This is often done to create genetically modified organisms.
141
What is a selectable marker in transgenic research?
A gene that confers resistance to an antibiotic
## Footnote
Selectable markers are used to identify successfully modified cells.
142
What is the purpose of the lactoglobulin promoter in mammalian transgenesis?
To target the expression of recombinant proteins in the milk of lactating females
## Footnote
This allows for the production of therapeutic proteins.
143
How are recombinant proteins produced in cell cultures?
Host cells are engineered to secrete the proteins
## Footnote
This simplifies the purification process for drugs like insulin.
144
What is gene therapy?
The alteration of an afflicted individual’s genes
## Footnote
Gene therapy aims to treat or prevent diseases caused by genetic defects.
145
What are induced pluripotent stem cells (iPS cells)?
Stem cells created by reprogramming adult cells
## Footnote
iPS cells can differentiate into various cell types and are a potential source for regenerative medicine.
146
True or False: Cloned animals always look and behave exactly the same as their genetic donors.
False
## Footnote
Cloned animals can exhibit differences due to epigenetic factors.
147
What are the two types of stem cells mentioned in the text?
* Embryonic stem cells (ES cells)
* Adult stem cells
## Footnote
ES cells can differentiate into all cell types, while adult stem cells can generate some specific types.
148
What is the primary function of transgenic animals?
To produce large amounts of proteins for medical use
## Footnote
These animals can act as pharmaceutical factories.
149
Fill in the blank: Gene therapy raises both technical and ______ issues.
[ethical]
## Footnote
Ethical considerations are critical in gene therapy, especially regarding the use of viral vectors.
150
**What is Hemagglutinin (HA) of immunity ?**
Flu shot is keep our anti‑HA antibodies in step with the virus's antigenic drift (mutation)
151
**What is Neuraminidase (NA) of immunity ?**
Drug targert: becuase NA's active site is conserved
