Module 2 stuff

Question 1

All of the following are potentially good sources of genomic DNA EXCEPT:

a. solid tissue
b. WBCs
c. mature RBCs
d. buccal cells

Answer 1

mature RBCs

Question 2

After isolating the DNA specimen, you assess the quality of the specimen prior to amplification. The mass spectrometry results read at 280 nm. This result suggests that:

Answer 2

the specimen is contaminated with left-over proteins

Question 3

What is the key enzyme used in a polymerase chain reaction (PCR)?

Answer 3

polymerase

Question 4

In real-time PCR:

a. the amount of signal generated is directly proportional to the amount of template
b. RNA targets are used in an isothermal reaction.
c. an isolated mRNA and Thermus thermophilus is used.
d. RNA:DNA hybrids are bound to a solid phase.

Answer 4

the amount of signal generated is directly proportional to the amount of template

Question 5

The annealing step in a PCR involves:

a. adding nucleotides to primed sites of the DNA strands.
b. binding of the primers to the single-stranded DNA.
c. unwinding and separating the double-stranded DNA.
d. making a cDNA from an mRNA strand.

Answer 5

binding of the primers to the single-stranded DNA

Question 6

During the extension phase of PCR:

a. oligonucleotide primers attach at ends of the strands to promote replication
b. the dsDNA separates
c. tRNA delivers a nucleotide to the appropriate position
d. heat-stable DNA polymerase synthesizes complementary strands

Answer 6

heat-stable DNA polymerase synthesizes complementary strands

Question 7

False positive results in molecular testing are most likely caused by which one of the following?

a. Inhibitors present in the sample
b. Using too little DNA
c. Contamination with outside DNA
d. Excessive washing

Answer 7

Contamination with outside DNA

Question 8

You want to determine the accuracy of hybridization of a probe to a Southern blot to eliminate binding of the probe to incorrect target sequences. Which one of the following would be an appropriate positive control to assess assay sensitivity?

a. Water
b. Sequences complementary to the probe
c. Sequences from a housekeeping gene such as beta actin
d. Sequences that are not complementary to the probe

Answer 8

Sequences complementary to the probe

Question 9

The purpose of restriction fragment polymorphism analysis (RFLP), which is the methodology of the Southern Blot, is to:

Answer 9

identify the presence of mutations or sequence changes

Question 10

You have prepared a restriction enzyme digest of DNA from an individual who might have a genetic disorder. On the gel, you note that the digest from this individual produces one fragment, whereas the digest from a normal healthy individual produces two fragments. All controls worked correctly and you used the same reagents for all testing. What is your interpretation?

Answer 10

The diseased individual’s DNA is missing a restriction site (a recognition sequence).

Question 11

In a pyrosequencing reaction, a single strand of DNA is used as a template to synthesize the complimentary strand. The instrument uses ___ to determine the results.

Answer 11

chemiluminescence

Question 12

The enzyme used to cleave nucleotides one at a time from the ends is:

Answer 12

an exonuclease

Question 13

The restriction endonuclease EcoRI recognizes ___ and produces a ___.

Answer 13

GAATTC ; staggered cut

Question 14

___ degrades nucleic acid.

Answer 14

nucleases

Question 15

___ catalyzes the synthesis of DNA from RNA or DNA templates.

Answer 15

reverse transcriptase

Question 16

___ covalently joins 2 DNA strands.

Answer 16

ligases

Question 17

What is the method of amplification used for this type of methodology?

Reverse transcriptase PCR

Answer 17

target

Question 18

What is the method of amplification used for this type of methodology?

Rolling circle amplification

Answer 18

probe

Question 19

What is the method of amplification used for this type of methodology?

Transcription mediated amplification

Answer 19

target

Question 20

What is the method of amplification used for this type of methodology?

Polymerase chain reaction

Answer 20

target

Question 21

What is the method of amplification used for this type of methodology?

Branched DNA

Answer 21

signal

Question 22

What is the method of amplification used for this type of methodology?

Serial invasive signal amplification

Answer 22

signal

Question 23

What is the method of amplification used for this type of methodology ?

Ligase chain reaction

Answer 23

target

Question 24

Name the enzyme(s) required for this type of methodology:

Reverse transcriptase PCR

Answer 24

1. reverse transcriptase

2. DNA polymerase

Question 25

Name the enzyme(s) required for this type of methodology:

Ligase chain reaction

Answer 25

DNA ligase

Question 26

Name the enzyme(s) required for this type of methodology:

WGA

Answer 26

processive DNA polymerase

Question 27

Name the enzyme(s) required for this type of methodology:

LAMP

Answer 27

DNA polymerase

Question 28

Name the enzyme(s) required for this type of methodology:

PCR

Answer 28

DNA polymerase

Question 29

A restriction enzyme recognizes the sequence:

5’CT ^ ATAG 3’

…and cuts as indicated by the “^”

What should be the complementary strand?

Answer 29

3’ GATA ^ TC 5’

Question 30

After 15 cycles of PCR, what is the estimated product of dsDNA?

Answer 30

32,768

Question 31

If a DNA probe is added to nitrocellulose after the transfer step but without performing the blocking step, which of the following will occur?

a. The probe will bind to the target.
b. Bound probe will be washed away in the next step.
c. The DNA target on the nitrocellulose will be unable to bind the probe.
d. Unoccupied spaces on the nitrocellulose will bind the probe.

Answer 31

Unoccupied spaces on the nitrocellulose will bind the probe.

Question 32

In the presence of salt, DNA is precipitated out from solution by:

Answer 32

Alcohols, such as 95% ethanol or isopropanol

Question 33

For the purpose of diagnosing a genetic disease, which of the following is the most useful component of whole blood to be used for the extraction of DNA?

a. Platelets
b. Plasma
c. Red blood cells
d. Leukocytes

Answer 33

Leukocytes

Question 34

In RNA, which nucleotide base replaces thymine of DNA?

Answer 34

uracil

Question 35

Which of the following regarding Loop-mediated amplification (LAMP) is NOT true?

a. LAMP uses a strand displacement methodology.
b. The LAMP procedure makes looped structures of differing sizes.
c. The LAMP procedure is isothermal.
d. LAMP’s main enzyme used is RNA ligase.

Answer 35

LAMP’s main enzyme used is RNA ligase

Question 36

All of the following are molecular diagnostic techniques that do NOT require electrophoresis EXCEPT:

a. Matrix-Assisted Laser-Desorption Ionization Time-of-flight (MALDI-TOF)
b. HIgh-throughput sequencing
c. Southern Blot
d. Pyrosequencing

Answer 36

Southern Blot

Question 37

What refers to a genetic element that does not code for a functional gene product?

Answer 37

pseudogenes

Question 38

On a Southern Blot, what happens if the washing step is insufficient?

Answer 38

It may cause a high background and non-interpretable results

Question 39

A blot which uses a DNA probe produced by reverse transcription of the messenger RNA is ___.

Answer 39

Northern Blot

Question 40

What is the correct temperature range for this step of PCR?

Denaturalization

Answer 40

94–95 degrees C

Question 41

What is the correct temperature range for this step of PCR?

Extension of DNA

Answer 41

72 degrees C

Question 42

What is the correct temperature range for this step of PCR?

Primer annealing

Answer 42

55–65 degrees C

Question 43

Thermus aquaticus, a microbe found in hot springs, is utilized in the lab to as ___.

Answer 43

Taq DNA polymerase

Question 44

What does Serial Invasive Signal Amplification do?

Answer 44

generates fluorescence to amplify the signal