Molecular Diagnostic Techniques: Master Microbiology Diagnostics

Question 1

Which of the following is NOT a molecular diagnostic technique used in microbiology?

Accepted Answer

Microscopy

Answer

Polymerase Chain Reaction (PCR)

Answer

DNA sequencing

Answer

Immunofluorescence

Question 2

What is the fundamental principle behind Polymerase Chain Reaction (PCR)?

Accepted Answer

Enzymatic amplification of a specific DNA sequence

Answer

Detection of antibodies against a specific antigen

Answer

Visualization of microorganisms under a microscope

Answer

Isolation of microorganisms in a culture medium

Question 3

What is the key difference between a qualitative and a quantitative molecular diagnostic test?

Accepted Answer

Qualitative tests detect presence/absence, while quantitative tests measure the amount of a target

Answer

Quantitative tests detect presence/absence, while qualitative tests measure the amount of a target

Answer

Both tests measure the amount of a target, but qualitative tests are more specific

Answer

Both tests detect presence/absence, but quantitative tests are more sensitive

Question 4

Which of the following is an example of a real-time PCR technique?

Accepted Answer

TaqMan PCR

Answer

Nested PCR

Answer

Reverse transcriptase PCR

Answer

Multiplex PCR

Question 5

Which component is NOT essential for a polymerase chain reaction (PCR)?

Accepted Answer

Restriction enzymes

Answer

DNA template

Answer

Primers

Answer

Polymerase

Question 6

What is the primary purpose of gel electrophoresis in molecular diagnostics?

Accepted Answer

To separate DNA fragments by size and charge

Answer

To amplify DNA

Answer

To sequence DNA

Answer

To detect mutations

Question 7

Which method is used to amplify a specific region of DNA during a PCR reaction?

Accepted Answer

Thermal cycling

Answer

Restriction digestion

Answer

DNA ligation

Answer

Electrophoresis

Question 8

Which molecular diagnostic technique utilizes nucleic acid hybridization?

Accepted Answer

DNA microarray

Answer

PCR

Answer

DNA sequencing

Answer

Restriction fragment length polymorphism (RFLP)

Question 9

What is the intended purpose of using a probe in molecular diagnostic techniques like Southern blotting?

Accepted Answer

To detect complementary DNA sequences

Answer

To amplify DNA

Answer

To digest DNA

Answer

To separate DNA fragments

Question 10

Which component is NOT essential for a polymerase chain reaction?

Accepted Answer

Restriction enzymes

Answer

DNA template

Answer

Primers

Answer

DNA polymerase

Question 11

What is the primary purpose of the denaturation step in PCR?

Accepted Answer

To break hydrogen bonds between complementary DNA strands

Answer

To allow primers to bind to the template DNA

Answer

To extend newly synthesized strands

Answer

To separate PCR products by size

Question 12

Which advantage does real-time PCR offer over traditional PCR?

Accepted Answer

Quantitative measurement of amplified DNA

Answer

Faster time to results

Answer

Greater sensitivity

Answer

Lower cost

Question 13

What is the primary role of Sanger sequencing in molecular diagnostics?

Accepted Answer

Determine the nucleotide sequence of DNA

Answer

Amplify DNA segments

Answer

Identify genetic variations

Answer

Detect specific microorganisms

Question 14

Which limitation is inherent to DNA microarrays in microbiology?

Accepted Answer

Limited multiplexing capacity

Answer

High cost

Answer

False positive results

Answer

Low sensitivity

Question 15

What is a primary value of phylogenetic trees in microbiology?

Accepted Answer

Studying evolutionary relationships among microorganisms

Answer

Identifying novel species

Answer

Developing diagnostic tests

Answer

Treating infectious diseases

Question 16

What is the key function of quality control in molecular diagnostic laboratories?

Accepted Answer

Ensure accurate and reliable results

Answer

Prevent contamination of samples

Answer

Train laboratory personnel

Answer

Develop new molecular diagnostic methods

Question 17

What significant advantage does next-generation sequencing offer in microbiology?

Accepted Answer

High throughput and speed

Answer

Low cost

Answer

High sensitivity

Answer

Wide range of applications

Question 18

What is the purpose of bioinformatics in analyzing molecular diagnostic data?

Accepted Answer

Process and analyze large datasets

Answer

Develop data management software

Answer

Design primers for PCR

Answer

Interpret genetic variants

Question 19

Which fundamental principle underlies the technique of PCR (Polymerase Chain Reaction)?

Accepted Answer

Enzymatic replication of complementary DNA strands

Answer

Disintegration of bacterial cells

Answer

Coloration of nucleic acid strands

Answer

Fragmentation of DNA

Question 20

In the field of microbiology, what is the primary objective of DNA sequencing?

Accepted Answer

Identification and characterization of microorganisms

Answer

Detection of drug resistance genes

Answer

Monitoring the evolution of pathogens

Answer

Quantifying microbial populations

Question 21

In PCR, which enzyme is responsible for synthesizing DNA?

Accepted Answer

Polymerase

Answer

Ligase

Answer

Nuclease

Answer

Topoisomerase

Question 22

In microbiology, what is the purpose of a phylogenetic tree?

Accepted Answer

Illustrating the evolutionary relationships between organisms

Answer

Visualizing microorganisms under a microscope

Answer

Cultivating bacteria in a laboratory setting

Answer

Analyzing DNA sequences using a computer program

Question 23

What is the function of a primer in PCR?

Accepted Answer

Binding to specific DNA regions and initiating synthesis

Answer

Cleaving amplified DNA fragments

Answer

Separating DNA bands during electrophoresis

Answer

Labeling DNA for detection

Question 24

Which technique is used to separate DNA fragments based on their size?

Accepted Answer

Gel electrophoresis

Answer

Flow cytometry

Answer

Mass spectrometry

Answer

X-ray crystallography

Question 25

In the context of PCR, the sequence that complementary to the ends of the target DNA and serves as a starting point for DNA polymerase is called:

Accepted Answer

Primer

Answer

Promoter

Answer

Terminator

Answer

Gene

Question 26

In Southern blotting, a labeled probe is used to specifically bind to complementary sequences on:

Accepted Answer

Detecting specific DNA sequences

Answer

Separating DNA fragments by size

Answer

Transferring DNA fragments to a membrane

Answer

Hybridizing the membrane with a labeled probe

Question 27

A potential ethical concern associated with molecular diagnostic testing is:

Accepted Answer

Genetic discrimination

Answer

False positives

Answer

False negatives

Answer

Cross-contamination

Question 28

The underlying principle of DNA sequencing is:

Accepted Answer

Determining the order of nucleotides in a DNA molecule

Answer

Targeted amplification of specific DNA regions

Answer

Separation of DNA fragments based on size

Answer

Visualizing DNA fragments under UV light

Question 29

In a molecular diagnostic assay, what is the primary purpose of employing a reverse transcriptase enzyme?

Accepted Answer

Convert RNA into DNA

Answer

Convert DNA into RNA

Answer

Amplify DNA

Answer

Detect proteins

Question 30

How are molecular diagnostic techniques used to construct a phylogenetic tree?

Accepted Answer

Comparing DNA sequences of different organisms

Answer

Analyzing protein structure

Answer

Measuring growth rates

Answer

Observing morphological characteristics

Question 31

What is the primary function of primers in PCR?

Accepted Answer

Binding to specific DNA sequences

Answer

Initiating DNA synthesis

Answer

Amplifying DNA

Answer

Detecting PCR products

Question 32

Which methods are utilized for DNA sequencing?

Accepted Answer

Both Sanger sequencing and NGS

Answer

Sanger sequencing

Answer

Next-generation sequencing (NGS)

Answer

Microarray

Question 33

Differentiate between qualitative and quantitative molecular diagnostic assays.

Accepted Answer

Qualitative assays detect presence/absence, while quantitative assays measure the amount of target

Answer

Quantitative assays detect presence/absence, while qualitative assays measure the amount of target

Answer

Both assays detect presence/absence

Answer

Both assays measure the amount of target

Question 34

Why is quality control crucial in molecular diagnostics? Describe specific measures used to guarantee accurate and reliable test results.

Accepted Answer

Quality control minimizes errors, ensuring accurate diagnoses and appropriate treatments.

Answer

Quality control is only important in large molecular diagnostic labs.

Answer

Quality control mainly focuses on monitoring equipment performance.

Answer

Quality control is unnecessary in molecular diagnostics due to its inherent accuracy.

Question 35

Which DNA polymerase is most frequently used in PCR?

Accepted Answer

Taq polymerase

Answer

Pfu polymerase

Answer

Tth polymerase

Answer

Vent polymerase

Question 36

What is the primary purpose of reverse transcriptase in molecular diagnostics?

Accepted Answer

Convert RNA into complementary DNA (cDNA)

Answer

Synthesize proteins

Answer

Amplify DNA fragments

Answer

Detect specific DNA sequences

Question 37

Which of the following is a primary function of a probe in a molecular diagnostic test?

Accepted Answer

Detect and bind to a specific target DNA or RNA sequence

Answer

Visualize a target sequence

Answer

Amplify a target sequence

Answer

Synthesize a target sequence

Question 38

Which of the following is a key advantage of using molecular diagnostic techniques over traditional methods?

Accepted Answer

Increased accuracy and sensitivity in detecting pathogens or genetic abnormalities

Answer

Elimination of the need for specialized equipment

Answer

Lower cost and shorter turnaround time

Answer

Wider applicability to a broader range of samples

Question 39

What is a significant limitation associated with the use of molecular diagnostic techniques in clinical practice?

Accepted Answer

Potential for false negatives due to factors such as low target concentration or assay variability

Answer

Inadequate training of laboratory personnel

Answer

Long turnaround time for results

Answer

High equipment and reagent costs

Question 40

When would nested PCR be the most suitable technique to employ?

Accepted Answer

When amplifying a very low concentration or degraded sample of target DNA

Answer

When amplifying a large fragment of DNA

Answer

When amplifying a DNA sample that contains inhibitors

Answer

When amplifying a repetitive sequence of DNA

Question 41

What is the main application of quantitative PCR (qPCR)?

Accepted Answer

Measuring the relative or absolute abundance of DNA or RNA sequences

Answer

Amplifying large fragments of DNA

Answer

Detecting mutations in a gene

Answer

Identifying unknown pathogens

Question 42

What is the fundamental role of quality control in molecular diagnostic testing?

Accepted Answer

Ensuring the accuracy, reliability, and consistency of test results

Answer

Minimizing the cost of testing

Answer

Reducing the turnaround time of testing

Answer

Training laboratory personnel