Medical Laboratory Technician Exam Molecular Diagnostics

Question 1

Which technique is used to amplify specific DNA sequences in molecular diagnostics?

Accepted Answer

Polymerase chain reaction (PCR)

Answer

Southern blot

Answer

Western blot

Answer

ELISA

Question 2

What is the purpose of the denaturation step in PCR?

Accepted Answer

To separate double-stranded DNA into single strands

Answer

To anneal primers to template DNA

Answer

To extend new DNA strands

Answer

To remove RNA from the sample

Question 3

Which enzyme is essential for the PCR amplification process?

Accepted Answer

Taq polymerase

Answer

RNA polymerase

Answer

Ligase

Answer

Restriction endonuclease

Question 4

In real-time PCR (qPCR), fluorescence is measured to:

Accepted Answer

Quantify the amount of target DNA during amplification

Answer

Determine the size of the amplified product

Answer

Identify the sequence of the amplicon

Answer

Detect chromosomal abnormalities

Question 5

Which molecular technique is used to detect RNA viruses such as HIV or SARS-CoV-2?

Accepted Answer

Reverse transcriptase PCR (RT-PCR)

Answer

Standard PCR

Answer

Southern blot

Answer

Pulsed-field gel electrophoresis

Question 6

What does a Southern blot technique detect?

Accepted Answer

Specific DNA sequences

Answer

Specific RNA sequences

Answer

Specific proteins

Answer

Specific antibodies

Question 7

Which specimen collection tube is most appropriate for molecular testing of whole blood?

Accepted Answer

Lavender top (EDTA)

Answer

Red top (no additive)

Answer

Yellow top (SPS)

Answer

Light blue top (sodium citrate)