QBM Exam 3 questions with complete
solutions A+ rated
Which of the following DNA purification techniques CANNOT be used for genomic DNA
purification? - correct answer ✔✔ miniprep
Which DNA purification technique involves purifying the sample using an ultracentrifuge? -
correct answer ✔✔ Cesium chloride gradient
What technique is used to increase plasmid copy number and purify plasmids? - correct answer
✔✔ Miniprep.
Which of the following wavelengths is incorrectly matched? - correct answer ✔✔ 240 nm - RNA
concentration.
The absorbance of a DNA sample at A260 = 1.0, and A280 = 1.0. Which of the following is TRUE?
- correct answer ✔✔ There is significant protein contamination of this sample
RNA is more difficult to work with than DNA because - correct answer ✔✔ the 2' hydroxyl group
causes RNA to be more susceptible to degradation.
Which of the following does NOT inhibit RNase activity? - correct answer ✔✔ EDTA
An advantage of agarose gel electrophoresis over SDS-PAGE is that - correct answer ✔✔ ALL (no
stacking gel is needed, DNA can be purified and extracted, SDS is not required to maintain an
equal charge-to-mass ratio, DNA can be loaded perpendicularly)
, The following DNA fragments are run on a gel. The DNA fragment in Lane 4 below is - correct
answer ✔✔ 600 bp
Ethidium bromide is frequently chosen to visualize DNA on a gel because - correct answer ✔✔ It
is more sensitive than SYBR Green and crystal violet
If Lane 1 contains undigested plasmid DNA and Lane 2 contains the same digested DNA sample,
which of the following is TRUE about the gel below? - correct answer ✔✔ The DNA sample has
a molecular weight of 4 kb.
Which of the following techniques is most appropriate for separating DNA fragments (>50 kb)
for genotyping? - correct answer ✔✔ Pulse-field gel electrophoresis.
What is the most sensitive DNA visualization method? - correct answer ✔✔ Autoradiography.
Which of the following is a downstream application of agarose gel electrophoresis? - correct
answer ✔✔ (ALL) DNA sequencing, Southern blotting for DNA samples, northern for RNA
sample
To extract DNA from a gel you would perform a - correct answer ✔✔ gel extraction and freeze
squeeze
A collection of cells that are all descendants from the same cell are called - correct answer ✔✔
clones
Which of the following is NOT a tool used in recombinant DNA technology? - correct answer
✔✔ Using primase to catalyze the formation of phosphodiester bonds.
Which of the following is TRUE about restriction enzymes? - correct answer ✔✔ They generally
recognize palindromic DNA
solutions A+ rated
Which of the following DNA purification techniques CANNOT be used for genomic DNA
purification? - correct answer ✔✔ miniprep
Which DNA purification technique involves purifying the sample using an ultracentrifuge? -
correct answer ✔✔ Cesium chloride gradient
What technique is used to increase plasmid copy number and purify plasmids? - correct answer
✔✔ Miniprep.
Which of the following wavelengths is incorrectly matched? - correct answer ✔✔ 240 nm - RNA
concentration.
The absorbance of a DNA sample at A260 = 1.0, and A280 = 1.0. Which of the following is TRUE?
- correct answer ✔✔ There is significant protein contamination of this sample
RNA is more difficult to work with than DNA because - correct answer ✔✔ the 2' hydroxyl group
causes RNA to be more susceptible to degradation.
Which of the following does NOT inhibit RNase activity? - correct answer ✔✔ EDTA
An advantage of agarose gel electrophoresis over SDS-PAGE is that - correct answer ✔✔ ALL (no
stacking gel is needed, DNA can be purified and extracted, SDS is not required to maintain an
equal charge-to-mass ratio, DNA can be loaded perpendicularly)
, The following DNA fragments are run on a gel. The DNA fragment in Lane 4 below is - correct
answer ✔✔ 600 bp
Ethidium bromide is frequently chosen to visualize DNA on a gel because - correct answer ✔✔ It
is more sensitive than SYBR Green and crystal violet
If Lane 1 contains undigested plasmid DNA and Lane 2 contains the same digested DNA sample,
which of the following is TRUE about the gel below? - correct answer ✔✔ The DNA sample has
a molecular weight of 4 kb.
Which of the following techniques is most appropriate for separating DNA fragments (>50 kb)
for genotyping? - correct answer ✔✔ Pulse-field gel electrophoresis.
What is the most sensitive DNA visualization method? - correct answer ✔✔ Autoradiography.
Which of the following is a downstream application of agarose gel electrophoresis? - correct
answer ✔✔ (ALL) DNA sequencing, Southern blotting for DNA samples, northern for RNA
sample
To extract DNA from a gel you would perform a - correct answer ✔✔ gel extraction and freeze
squeeze
A collection of cells that are all descendants from the same cell are called - correct answer ✔✔
clones
Which of the following is NOT a tool used in recombinant DNA technology? - correct answer
✔✔ Using primase to catalyze the formation of phosphodiester bonds.
Which of the following is TRUE about restriction enzymes? - correct answer ✔✔ They generally
recognize palindromic DNA
