AMT Molecular Diagnostics Technologist
(MDT) certification exam questions and correct
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1. Which technique is most commonly used to amplify DNA in molecular
diagnostics?
A. ELISA
B. Western blot
C. Polymerase Chain Reaction (PCR)
D. Flow cytometry
Answer: C. Polymerase Chain Reaction (PCR)
Rationale: PCR selectively amplifies specific DNA sequences, making it a
foundational technique in molecular diagnostics.
2. What is the primary function of primers in PCR?
A. Digest DNA
B. Initiate DNA synthesis
C. Visualize DNA fragments
D. Stabilize proteins
Answer: B. Initiate DNA synthesis
Rationale: Primers provide the starting point for DNA polymerase to begin
replication.
3. Which enzyme is commonly used in PCR?
,A. Restriction endonuclease
B. Reverse transcriptase
C. Taq polymerase
D. Ligase
Answer: C. Taq polymerase
Rationale: Taq polymerase is heat-stable and remains active during thermal
cycling.
4. The denaturation step in PCR typically occurs at:
A. 37°C
B. 55°C
C. 72°C
D. 94–95°C
Answer: D. 94–95°C
Rationale: High temperatures separate the DNA strands before amplification.
5. What is the purpose of gel electrophoresis?
A. Amplify DNA
B. Separate nucleic acids by size
C. Sequence DNA
D. Digest proteins
Answer: B. Separate nucleic acids by size
Rationale: DNA fragments migrate through a gel matrix according to their
molecular size.
6. Which nucleic acid contains uracil instead of thymine?
,A. DNA
B. RNA
C. cDNA
D. mtDNA
Answer: B. RNA
Rationale: RNA contains uracil as one of its nitrogenous bases.
7. Reverse transcription converts:
A. DNA to protein
B. RNA to DNA
C. Protein to RNA
D. DNA to RNA
Answer: B. RNA to DNA
Rationale: Reverse transcriptase synthesizes complementary DNA (cDNA) from
RNA templates.
8. Which method is commonly used to detect RNA viruses?
A. RT-PCR
B. Southern blot
C. Karyotyping
D. ELISA only
Answer: A. RT-PCR
Rationale: Reverse transcription PCR first converts RNA to cDNA before
amplification.
9. A mutation involving a single nucleotide change is called:
, A. Inversion
B. Deletion
C. SNP
D. Translocation
Answer: C. SNP
Rationale: Single nucleotide polymorphisms involve substitution of one nucleotide.
10. Which sequencing technology is considered first-generation sequencing?
A. Nanopore sequencing
B. Sanger sequencing
C. Illumina sequencing
D. Pyrosequencing
Answer: B. Sanger sequencing
Rationale: Sanger sequencing was the original DNA sequencing method.
11. What is the purpose of a positive control?
A. Detect contamination
B. Verify assay performance
C. Eliminate false positives
D. Measure specimen volume
Answer: B. Verify assay performance
Rationale: Positive controls ensure the test system can detect the target.
12. A negative control should contain:
A. Known target DNA
B. Internal control DNA
(MDT) certification exam questions and correct
answers(verified answers) q$a 2026/ instant
download pdf
1. Which technique is most commonly used to amplify DNA in molecular
diagnostics?
A. ELISA
B. Western blot
C. Polymerase Chain Reaction (PCR)
D. Flow cytometry
Answer: C. Polymerase Chain Reaction (PCR)
Rationale: PCR selectively amplifies specific DNA sequences, making it a
foundational technique in molecular diagnostics.
2. What is the primary function of primers in PCR?
A. Digest DNA
B. Initiate DNA synthesis
C. Visualize DNA fragments
D. Stabilize proteins
Answer: B. Initiate DNA synthesis
Rationale: Primers provide the starting point for DNA polymerase to begin
replication.
3. Which enzyme is commonly used in PCR?
,A. Restriction endonuclease
B. Reverse transcriptase
C. Taq polymerase
D. Ligase
Answer: C. Taq polymerase
Rationale: Taq polymerase is heat-stable and remains active during thermal
cycling.
4. The denaturation step in PCR typically occurs at:
A. 37°C
B. 55°C
C. 72°C
D. 94–95°C
Answer: D. 94–95°C
Rationale: High temperatures separate the DNA strands before amplification.
5. What is the purpose of gel electrophoresis?
A. Amplify DNA
B. Separate nucleic acids by size
C. Sequence DNA
D. Digest proteins
Answer: B. Separate nucleic acids by size
Rationale: DNA fragments migrate through a gel matrix according to their
molecular size.
6. Which nucleic acid contains uracil instead of thymine?
,A. DNA
B. RNA
C. cDNA
D. mtDNA
Answer: B. RNA
Rationale: RNA contains uracil as one of its nitrogenous bases.
7. Reverse transcription converts:
A. DNA to protein
B. RNA to DNA
C. Protein to RNA
D. DNA to RNA
Answer: B. RNA to DNA
Rationale: Reverse transcriptase synthesizes complementary DNA (cDNA) from
RNA templates.
8. Which method is commonly used to detect RNA viruses?
A. RT-PCR
B. Southern blot
C. Karyotyping
D. ELISA only
Answer: A. RT-PCR
Rationale: Reverse transcription PCR first converts RNA to cDNA before
amplification.
9. A mutation involving a single nucleotide change is called:
, A. Inversion
B. Deletion
C. SNP
D. Translocation
Answer: C. SNP
Rationale: Single nucleotide polymorphisms involve substitution of one nucleotide.
10. Which sequencing technology is considered first-generation sequencing?
A. Nanopore sequencing
B. Sanger sequencing
C. Illumina sequencing
D. Pyrosequencing
Answer: B. Sanger sequencing
Rationale: Sanger sequencing was the original DNA sequencing method.
11. What is the purpose of a positive control?
A. Detect contamination
B. Verify assay performance
C. Eliminate false positives
D. Measure specimen volume
Answer: B. Verify assay performance
Rationale: Positive controls ensure the test system can detect the target.
12. A negative control should contain:
A. Known target DNA
B. Internal control DNA
