Clinical Laboratory Techniques & Procedures Flashcards
7 cards from real CLT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Clinical Laboratory Techniques & Procedures flashcards as text
Which centrifuge speed is most appropriate for separating serum from a whole blood specimen?
Answer: 2,000–3,000 rpm for 10 minutes
Routine serum separation requires centrifugation at approximately 2,000–3,000 rpm for 10 minutes to pellet cells without hemolysis.
A laboratory technologist notices a clot in an EDTA tube collected for a CBC. What is the most appropriate action?
Answer: Recollect the specimen from the patient
Clotted EDTA specimens are unsuitable for CBC analysis and must be recollected because platelet counts and cell morphology will be inaccurate.
The delta check system in laboratory information systems is primarily used to:
Answer: Compare a current result with a previous result from the same patient
Delta checks compare current patient results against prior results to detect specimen mix-ups, labeling errors, or unexpected clinical changes.
When performing a manual differential on a peripheral blood smear, the technologist should count how many cells?
Answer: 100 WBCs
The standard manual differential requires counting 100 WBCs in the monolayer area of the smear to classify cell types as percentages.
Which specimen type is required for a plasma renin activity (PRA) test?
Answer: EDTA plasma (lavender-top tube)
PRA requires EDTA plasma collected on ice because EDTA chelates calcium to inhibit angiotensin-converting enzyme and the cold slows enzymatic degradation.
A 2% sodium hypochlorite (bleach) solution is used in the clinical laboratory primarily as a:
Answer: Surface decontaminant for blood spills
A 1:10 dilution of household bleach (≈0.5%) or 1:5 dilution (≈1%) is the standard decontaminant for blood and body-fluid spills on bench surfaces.
Which of the following best describes the purpose of an internal standard in quantitative mass spectrometry assays?
Answer: It corrects for matrix effects and variability in extraction efficiency
An isotope-labeled internal standard co-elutes with the analyte and compensates for ion suppression, extraction losses, and injection-to-injection variability.