🩺 Q453: [Hematology & Hemostasis Case (Series #2, Case #3)] In automated hematology analyzers, the Coulter impedance principle detects cells by measuring:
Anonymous Quiz
0%
A) Light scatter intensity at 90 degrees
100%
B) Electrical resistance change as non-conductive cells pass an aperture
0%
C) Fluorescence emission after nucleic acid staining
0%
D) Radiofrequency conductivity absorption
🩺 Q454: A clinical lab uses a freezing-point depression osmometer. If a patient sample is contaminated with ethanol, how will this affect the measured osmolality?
Anonymous Quiz
0%
A) The osmolality will be falsely decreased
73%
B) The osmolality will be falsely increased
9%
C) The osmolality will remain unchanged
18%
D) The measurement will fail due to instrument error
🩺 Q456: [Hematology & Hemostasis Case (Series #2, Case #4)] Which anticoagulant is the gold standard for routine Prothrombin Time (PT) and APTT testing?
Anonymous Quiz
0%
A) K2-EDTA
9%
B) Lithium Heparin
91%
C) Sodium Citrate (3.2%, 0.109 M)
0%
D) Potassium Oxalate
🩺 Q456: A laboratory scientist is preparing to separate serum from a clotted blood specimen. What is the primary safety concern regarding the use of a centrifuge without a sealed rotor or bucket covers?
Anonymous Quiz
0%
A) Mechanical failure of the motor
73%
B) Formation and inhalation of biohazardous aerosols
9%
C) Overheating of the specimen
18%
D) Uneven distribution of centrifugal force
🩺 Q458: [Hematology & Hemostasis Case (Series #3, Case #5)] In automated hematology analyzers, the Coulter impedance principle detects cells by measuring:
Anonymous Quiz
0%
A) Light scatter intensity at 90 degrees
92%
B) Electrical resistance change as non-conductive cells pass an aperture
8%
C) Fluorescence emission after nucleic acid staining
0%
D) Radiofrequency conductivity absorption
🩺 Q459: In a competitive immunoassay, what is the relationship between the concentration of the analyte in the patient sample and the measured signal?
Anonymous Quiz
8%
A) Directly proportional
42%
B) Inversely proportional
33%
C) Exponentially proportional
17%
D) Logarithmically proportional
🩺 Q460: A Levey-Jennings chart shows a 'trend' in QC results over the last 6 days, where values are progressively increasing. What is the most likely cause?
Anonymous Quiz
17%
A) Random error
42%
B) Deterioration of reagents or light source
42%
C) Sudden change in the calibration setting
0%
D) Operator error in pipetting
🩺 Q460: [Clinical Biochemistry Case (Series #2, Case #3)] Which cardiac biomarker demonstrates the highest myocardial specificity and remains elevated up to 10-14 days following acute MI?
Anonymous Quiz
33%
A) Creatine Kinase-MB (CK-MB)
0%
B) Myoglobin
58%
Cardiac Troponin I (cTnI)
8%
D) Lactate Dehydrogenase (LDH-1)
🩺 Q462: What is the primary purpose of a Safety Data Sheet (SDS) in the laboratory?
Anonymous Quiz
0%
A) To provide instructions on test methodology
8%
B) To document employee training hours
92%
C) To communicate information regarding chemical hazards and handling precautions
0%
D) To list the inventory of laboratory supplies
🩺 Q462: [Clinical Biochemistry Case (Series #2, Case #4)] In arterial blood gas analysis, an uncompensated metabolic acidosis is typically characterized by:
Anonymous Quiz
50%
A) Decreased pH, decreased HCO3-, and normal PaCO2
50%
B) Decreased pH, increased PaCO2, and normal HCO3-
0%
C) Increased pH, decreased PaCO2, and increased HCO3-
0%
D) Normal pH, normal PaCO2, and decreased HCO3-
🩺 Q464: What is the purpose of 'blind' proficiency testing samples in a clinical laboratory?
Anonymous Quiz
0%
A) To test the proficiency of the instrument only
100%
B) To ensure that samples are treated exactly like patient samples, preventing bias
0%
C) To reduce the cost of quality assurance
0%
D) To compare results between different hospitals
🩺 Q464: [Clinical Biochemistry Case (Series #3, Case #5)] Which cardiac biomarker demonstrates the highest myocardial specificity and remains elevated up to 10-14 days following acute MI?
Anonymous Quiz
42%
A) Creatine Kinase-MB (CK-MB)
8%
B) Myoglobin
42%
Cardiac Troponin I (cTnI)
8%
D) Lactate Dehydrogenase (LDH-1)
🩺 Q466: A method has high precision but low accuracy. How is this best described?
Anonymous Quiz
0%
A) The results are close to the true value but show wide scatter
82%
B) The results are clustered tightly together but are far from the true value
0%
C) The results are scattered and far from the true value
18%
D) The results are tightly clustered and close to the true value
🩺 Q466: [Clinical Biochemistry Case (Series #3, Case #6)] In arterial blood gas analysis, an uncompensated metabolic acidosis is typically characterized by:
Anonymous Quiz
58%
A) Decreased pH, decreased HCO3-, and normal PaCO2
25%
B) Decreased pH, increased PaCO2, and normal HCO3-
17%
C) Increased pH, decreased PaCO2, and increased HCO3-
0%
D) Normal pH, normal PaCO2, and decreased HCO3-
🩺 Q467: When handling concentrated acids or bases, which safety practice is mandatory?
Anonymous Quiz
9%
Add water to the acid to dilute
36%
B) Add the acid to the water slowly
55%
C) Use a standard fume hood without airflow monitoring
0%
D) Store acids and bases in the same cabinet
🩺 Q469: [Clinical Biochemistry Case (Series #4, Case #7)] Which cardiac biomarker demonstrates the highest myocardial specificity and remains elevated up to 10-14 days following acute MI?
Anonymous Quiz
36%
A) Creatine Kinase-MB (CK-MB)
9%
B) Myoglobin
55%
Cardiac Troponin I (cTnI)
0%
D) Lactate Dehydrogenase (LDH-1)
🩺 Q470: [Clinical Biochemistry Case (Series #4, Case #8)] In arterial blood gas analysis, an uncompensated metabolic acidosis is typically characterized by:
Anonymous Quiz
55%
A) Decreased pH, decreased HCO3-, and normal PaCO2
18%
B) Decreased pH, increased PaCO2, and normal HCO3-
27%
C) Increased pH, decreased PaCO2, and increased HCO3-
0%
D) Normal pH, normal PaCO2, and decreased HCO3-
🩺 Q471: [Clinical Biochemistry Case (Series #5, Case #9)] Which cardiac biomarker demonstrates the highest myocardial specificity and remains elevated up to 10-14 days following acute MI?
Anonymous Quiz
33%
A) Creatine Kinase-MB (CK-MB)
0%
B) Myoglobin
67%
Cardiac Troponin I (cTnI)
0%
D) Lactate Dehydrogenase (LDH-1)
🩺 Q472: [Clinical Biochemistry Case (Series #5, Case #10)] In arterial blood gas analysis, an uncompensated metabolic acidosis is typically characterized by:
Anonymous Quiz
45%
A) Decreased pH, decreased HCO3-, and normal PaCO2
27%
B) Decreased pH, increased PaCO2, and normal HCO3-
27%
C) Increased pH, decreased PaCO2, and increased HCO3-
0%
D) Normal pH, normal PaCO2, and decreased HCO3-
🩺 Q473: A patient presents with a persistent, non-healing foot ulcer. A tissue biopsy is sent for culture. After 48 hours of incubation on blood agar, small, non-hemolytic colonies are observed. The organism is catalase-negative, bile esculin-positive, and grows in 6.5% NaCl. Which of the following
Anonymous Quiz
33%
A) Streptococcus pyogenes
33%
B) Enterococcus faecalis
17%
C) Staphylococcus aureus
17%
D) Streptococcus agalactiae