Med Tech Quiz
Questions: 16 · 10 minutes
1. Which method describes the primary sterilizing action of a standard steam autoclave?
Continuous ultraviolet exposure at room temperature
Filtration through a membrane with microscopic pores
Saturated steam under pressure applied for a validated time and temperature
Dry heat combined with chemical disinfectant vapor
2. In an automated hematology analyzer, what happens during electrical impedance cell counting?
Cells emit light after binding a radioactive tracer.
Cells are identified solely by their sedimentation speed.
Cells passing through an aperture produce changes in electrical resistance.
Cells generate voltage through metabolic activity.
3. Which expression defines the diagnostic sensitivity of a test?
True negatives divided by all people without the condition
True positives divided by all positive test results
True negatives divided by all negative test results
True positives divided by all people who have the condition
4. What is a central purpose of a laboratory information system (LIS)?
To create medical images from X-ray detector signals
To manage laboratory orders, specimen data, instrument interfaces, and results
To sterilize reusable instruments and track exposure temperature
To replace analyzer calibration and internal quality control
5. A technologist wants to determine the actual distance represented by divisions on a microscope's ocular scale. Which tool should be used for calibration?
A stage micrometer with a known measurement scale
A color reference standard
A hemocytometer cover glass
A refractometer calibration solution
6. A patient has strong clinical signs of an extremely high hormone concentration, but a sandwich immunoassay reports an unexpectedly low value. Dilution produces a much higher result. What best explains this?
Improved precision caused by random error
A high-dose hook effect caused by analyte excess
Complete loss of analyte during centrifugation
A reference interval that is too broad
7. Before starting a centrifuge, how should a single specimen tube be balanced?
Place it next to the rotor hinge with an empty space opposite it.
Increase the speed gradually so no balancing tube is needed.
Place the heaviest available tube in any other rotor position.
Place a tube of equal mass directly opposite it in a symmetric rotor position.
8. Repeated measurements of the same control sample cluster tightly together but remain far from the target value. How should this performance be described?
Accurate but not precise
Neither measurable nor reportable solely because the values are close together
Both accurate and precise
Precise but not accurate
9. What is the main function of primers in a polymerase chain reaction (PCR)?
They separate DNA strands by breaking hydrogen bonds.
They produce the fluorescent signal without participating in amplification.
They cut amplified DNA into fragments after each cycle.
They define the target region and provide starting points for DNA synthesis.
10. A conventional laboratory reference interval is commonly established to include which portion of values from an appropriately selected reference population?
Every observed value, including all outliers
Only values above the population median
The central 95% of values
The lowest 5% of observed values
11. A visibly hemolyzed serum sample is tested without being recollected. Which result is especially likely to be falsely increased because red blood cells release their contents?
Chloride
Sodium
Potassium
Bicarbonate
12. The name on a specimen tube does not match the name attached to its electronic order. What should the technologist do?
Use the electronic order because digital records take priority over labels.
Stop processing and resolve the identification problem according to policy, which may require recollection.
Test the specimen and ask the care team to identify it after results are available.
Replace the tube label using the most likely patient information.
13. A pulse oximeter gives rapidly fluctuating readings on a patient whose fingers are cold and who is shivering. Which factor most directly reduces confidence in the reading?
The device measures oxygen through arterial blood sampling.
Poor peripheral perfusion and motion can interfere with the optical signal.
The sensor requires the patient to be fasting.
Pulse oximetry cannot measure oxygen saturation outside a laboratory.
14. Which anticoagulant is routinely used in a collection tube for a complete blood count because it preserves cellular morphology well?
EDTA
Sodium fluoride
Clot activator
Heparin gel used for plasma chemistry
15. A quality-control result falls outside the laboratory's acceptable range before patient samples are processed. What is the most appropriate immediate response?
Pause patient testing and investigate the control failure according to procedure.
Adjust the patient reference interval to match the control.
Run patient samples and add a note to each result.
Average the failed control with the previous acceptable control.
16. A sealed blood-gas specimen remains untested at room temperature for too long. If cells continue metabolizing, which pattern is generally expected?
Lower pH, higher carbon dioxide, and lower oxygen
Unchanged pH with higher oxygen and unchanged carbon dioxide
Higher pH, lower carbon dioxide, and higher oxygen
Higher pH, higher carbon dioxide, and lower oxygen