Which statement distinguishes calibration from verification in instrument quality control?
Anonymous Quiz
78%
A) Calibration adjusts instrument performance; verification confirmsongoing performance
17%
B) Verification replaces calibration when bias is detected
2%
C) Calibration uses patient samples only
2%
D) Verification increases the calibration frequency unnecessarily
Which PPE is most appropriate when handling volatile solvents in the laboratory?
Anonymous Quiz
4%
A) Safety glasses only
96%
B) Lab coat, gloves, and eye protection; chemical splash goggles; possible respirator
0%
C) None
0%
D) Only gloves
A 30-year-old woman with iron deficiency anemia has a reticulocyte count of 0.8% (normal 0.5-2.5%). This indicates:
Anonymous Quiz
31%
A) Appropriate marrow response to anemia
31%
B) Inadequate marrow response to anemia
33%
C) Marked reticulocytosis due to hemolysis
5%
D) Recent blood loss with transient reticulocytosis
In a colorimetric assay, what is the primary purpose of generating a standard curve?
Anonymous Quiz
5%
A) To determine the sample's color intensity
73%
B) To relate absorbance to known concentrations for quantification
22%
C) To calibrate the spectrophotometer wavelength accuracy
0%
D) To adjust pH of reagents
Which order correctly lists the steps of a conventional Gram stain?
Anonymous Quiz
86%
A) Crystal violet -> iodine -> decolorization with ethanol -> safranin
11%
B) Crystal violet -> safranin -> iodine -> decolorization
3%
C) Iodine -> crystal violet -> decolorization -> safranin
0%
D) Safranin -> crystal violet -> iodine -> decolorization
In an ELISA, which control is essential to validate that a negative result is truly negative?
Anonymous Quiz
19%
A) Positive control
62%
B) Negative control
16%
C) Substrate control
3%
D) Enzyme control
What does hematoxylin primarily stain in tissue sections?
Anonymous Quiz
14%
A) Cytoplasmic proteins
80%
B) Nucleic acids (basophilic nuclei)
3%
C) Collagen fibers
3%
D) Lipids
Which of the following is most likely associated with a positive nitrite dipstick result?
Anonymous Quiz
6%
A) Leukocyte esterase
14%
B) Urobilinogen
75%
C) Bacteriuria due to Gram-negative organisms
6%
D) Proteinuria
Which type of problem usually explains an ABO typing discrepancy due to cold-reactive antibodies?
Anonymous Quiz
6%
A) Secretor status
18%
B) Rouleaux interference
65%
C) Cold agglutinins (IgM)
12%
D) Hemolytic disease of the newborn
Which of the following is a key step in maintaining pipette accuracy?
Anonymous Quiz
18%
A) Calibration with water at room temperature
58%
B) Regular adjustment of the display to the measured value
3%
C) Using a rubber tip only
21%
D) Measuring volume at the instrument's maximum range only
What information is primarily found on a Safety Data Sheet (SDS) for a chemical?
Anonymous Quiz
3%
A) Tax classification
91%
B) Handling, exposure controls, and emergency measures
6%
C) Supplier's marketing details
0%
D) Temperature coefficients
A patient presents with MCV 105 fL, normal MCHC, and elevated RDW. This pattern is most consistent with:
Anonymous Quiz
65%
A) Macrocytic anemia
27%
B) Microcytic anemia
8%
C) Normocytic anemia
0%
D) Hypochromic anemia
Which lipid parameter is most dependent on fasting state for accurate measurement?
Anonymous Quiz
6%
A) HDL cholesterol
64%
B) LDL cholesterol calculated from triglycerides
19%
C) Triglycerides
11%
D) Total cholesterol
Which organism is typically oxidase positive?
Anonymous Quiz
25%
A) Escherichia coli
53%
B) Streptococcus pyogenes
19%
C) Neisseria meningitidis
3%
D) Listeria monocytogenes
Which antibody isotype is primarily responsible for mucosal immunity?
Anonymous Quiz
0%
A) IgG
73%
B) IgA
27%
C) IgM
0%
D) IgE
Which fixative is commonly used for Pap smear slide preservation?
Anonymous Quiz
18%
A) Formalin
77%
B) Ethanol-based fixative
3%
C) Methanol
3%
D) Glutaraldehyde
Which finding in urine sediment is most specific for glomerular disease?
Anonymous Quiz
33%
A) Erythrocyte casts
5%
B) Bacteria
51%
C) Calcium oxalate crystals
10%
D) Uric acid crystals
Which antibody is commonly implicated in hemolytic disease of the fetus and newborn due to the Rh(D) antigen?
Anonymous Quiz
10%
A) Anti-A
15%
B) Anti-B
73%
C) Anti-D (Rh)
3%
D) Anti-Kell
What is the primary purpose of Westgard rules in internal quality control?
Anonymous Quiz
5%
A) To set unit conversion factors
82%
B) To identify outside the control limits and false rejection/acceptance
10%
C) To calibrate instruments
3%
D) To schedule maintenance
Which biosafety level requires work with human blood in risk group 2 agents, use of Class II biological safety cabinet, and restricted access?
Anonymous Quiz
15%
A) BSL-1
62%
B) BSL-2
18%
C) BSL-3
5%
D) BSL-4