Basic Laboratory Procedures and Specimen Handling Flashcards
6 cards from real NCMA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Basic Laboratory Procedures and Specimen Handling flashcards as text
Which of the following best describes hemolysis in a blood specimen?
Answer: Rupture of red blood cells releasing hemoglobin into the serum
Hemolysis occurs when red blood cells rupture, releasing intracellular contents (hemoglobin, potassium, enzymes) into the serum, causing the specimen to appear pink or red and falsely elevating certain analytes.
What is the minimum volume of urine typically required for a routine urinalysis?
Answer: 10–12 mL
A minimum of 10–12 mL of urine is generally sufficient for a routine urinalysis including dipstick, microscopic examination, and color/clarity assessment in most laboratory protocols.
Which safety symbol on a laboratory reagent indicates a biohazard?
Answer: A trefoil-like symbol with three interlocking circles on an orange background
The biohazard symbol — a distinctive three-lobed trefoil on an orange or fluorescent background — identifies materials that contain biological agents capable of causing disease in humans.
A medical assistant performs a dipstick urinalysis and notes a glucose result of 2+. What should be the next step?
Answer: Report the result and alert the provider for follow-up
A 2+ glucose on dipstick urinalysis is a significant finding that must be reported to the provider; it may indicate hyperglycemia, diabetes, or renal glycosuria requiring further diagnostic workup.
What is the correct order of steps for performing a capillary puncture on a fingertip?
Answer: Select site → cleanse with alcohol → allow to dry → puncture → wipe away first drop → collect specimen
The correct sequence for fingerstick is site selection, cleansing with 70% isopropyl alcohol, allowing full drying, puncturing perpendicular to the fingerprint, discarding the first drop (contaminated with tissue fluid), then collecting the specimen.
Which of the following additives in a gray-top tube prevents glucose from being consumed by red blood cells?
Answer: Sodium fluoride
Sodium fluoride in gray-top tubes inhibits the enzyme enolase in the glycolytic pathway, preventing red blood cells and bacteria from consuming glucose and preserving the specimen for up to 24 hours at room temperature.