Medical Laboratory Technician Exam Molecular Diagnostics 3

Question 1

Restriction fragment length polymorphism (RFLP) analysis uses which enzymes?

Accepted Answer

Restriction endonucleases

Answer

DNA polymerases

Answer

Ligases

Answer

Topoisomerases

Question 2

Which molecular method is used to detect MRSA (methicillin-resistant Staphylococcus aureus)?

Accepted Answer

Detection of the mecA gene by PCR

Answer

Detection of rRNA by Southern blot

Answer

Protein gel electrophoresis

Answer

Microagglutination test

Question 3

What is the primary purpose of a melting curve analysis in real-time PCR?

Accepted Answer

To confirm amplicon identity and detect mutations or SNPs

Answer

To quantify the viral load

Answer

To determine sample purity

Answer

To measure primer efficiency

Question 4

Gel electrophoresis separates DNA fragments based on:

Accepted Answer

Fragment size (number of base pairs)

Answer

Molecular weight and charge

Answer

GC content

Answer

Degree of methylation

Question 5

Which of the following is a common inhibitor of PCR found in blood specimens?

Accepted Answer

Heparin

Answer

EDTA

Answer

Sodium citrate

Answer

Lithium heparin versus regular heparin (both equally inhibit)

Question 6

Loop-mediated isothermal amplification (LAMP) differs from PCR in that LAMP:

Accepted Answer

Amplifies DNA at a constant temperature without thermal cycling

Answer

Requires a thermal cycler with precise temperature changes

Answer

Can only detect RNA targets

Answer

Produces longer amplicons than PCR

Question 7

Which technique uses labeled probes hybridized to target nucleic acid on a membrane to detect gene expression patterns?

Accepted Answer

Northern blot

Answer

Western blot

Answer

PCR

Answer

Flow cytometry