DNA Structure and Bonding

What is the number of hydrogen bonds between Guanine (G) and Cytosine (C) in DNA?

2
3 (correct)
1
4

Which of the following is NOT a characteristic of the double helical model of DNA?

The sugar molecules are found at the center of the molecule (correct)
The strands can rejoin in a complementary manner
The strands can separate and act as a template
The two strands are antiparallel

What is the significance of the major and minor grooves in DNA?

They are the sites of DNA transcription
They are the sites of hydrogen bond formation
They are the sites of DNA replication
They are the sites of protein-DNA interaction (correct)

What is the outcome of semiconservative replication in DNA?

One parental DNA strand and one newly synthesized complementary strand are formed (A) Signup and view all the answers

What is the significance of the Meselson-Stahl experiments?

They demonstrated the semiconservative replication of DNA (D) Signup and view all the answers

What is the term for the bond that links the sugar molecule to the phosphate group in DNA?

Glycosidic bond (B) Signup and view all the answers

During DNA replication, what is the direction of synthesis for each new strand?

5’ to 3’ (B) Signup and view all the answers

What is the primary function of DNA Gyrase in prokaryotic DNA replication?

To facilitate future replication by introducing negative supercoils (A) Signup and view all the answers

What is the significance of multiple sites of origin in eukaryotic chromosomes?

It allows for bidirectional replication (B) Signup and view all the answers

What is the characteristic of semiconservative replication?

One strand is derived from the mother cell, while the other strand is synthesized from scratch (C) Signup and view all the answers

What is the role of each strand in DNA replication?

Each strand serves as a template for the synthesis of the other strand (A) Signup and view all the answers

What is the consequence of negative supercoils in eukaryotic DNA?

They neutralize positive supercoils introduced during double helix opening (A) Signup and view all the answers

What is the primary purpose of amplification controls in PCR-based tests?

To avoid false-negative results (A) Signup and view all the answers

What is the function of internal controls in quantitative PCR methods?

To determine the relative amounts of target (D) Signup and view all the answers

What is the purpose of calibrators in quantitative analyte measurements?

To associate the instrument response with the true value (A) Signup and view all the answers

What is the main goal of Quality Assurance (QA) in laboratory testing services?

To continuously improve the efficiency and reliability of laboratory testing services (C) Signup and view all the answers

What is the function of Quality Indicator Monitoring in QA?

To track the performance of the laboratory testing services (D) Signup and view all the answers

What is the purpose of Standard Operating Procedures (SOPs) in QA?

To outline the steps for laboratory testing services (C) Signup and view all the answers

What is the primary purpose of molecular diagnostics in laboratory medicine?

To diagnose human diseases at the nucleic acid level (C) Signup and view all the answers

What is the role of real-time reverse transcription polymerase chain reaction (rRT-PCR) in laboratory diagnosis for SARS-CoV-2?

Laboratory-based diagnosis of SARS-CoV-2 (C) Signup and view all the answers

What is the main application of genome-based diagnostics in molecular laboratory?

Diagnostic, prognostic, predictive, and therapeutic applications (B) Signup and view all the answers

What is the difference between laboratory-based and point-of-care molecular testing for SARS-CoV-2?

Point-of-care testing is performed at the patient's bedside, while laboratory-based testing is performed in a laboratory setting (C) Signup and view all the answers

What is the role of isothermal NAAT in molecular diagnostics for SARS-CoV-2?

Alternative to rRT-PCR for SARS-CoV-2 testing (C) Signup and view all the answers

What is the primary advantage of molecular diagnostics in molecular laboratory?

Ability to diagnose human diseases at the nucleic acid level (C) Signup and view all the answers

What is the primary purpose of External Quality Assessment?

To compare a laboratory's testing performance to the performance of peer or reference laboratories (D) Signup and view all the answers

What occurs when any of the quality control measures fail?

The test results are considered invalid and must be repeated (B) Signup and view all the answers

What is the purpose of proficiency testing?

To compare the performance of different laboratories (B) Signup and view all the answers

What is the purpose of reagent preparation in the analytical phase?

To prepare diagnostic reagents for testing (B) Signup and view all the answers

What is the final phase of the laboratory testing process?

Post-analytical phase (D) Signup and view all the answers

What is the purpose of sending blind samples to participating laboratories in proficiency testing?