Medical Laboratory Technician MCQ 1 Flashcards
6 cards from real Medical Laboratory Technician Exam practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Medical Laboratory Technician MCQ 1 flashcards as text
Which tube color is used for coagulation studies such as PT and aPTT?
Answer: Light blue-top (sodium citrate)
Light blue-top tubes contain sodium citrate, a calcium-chelating anticoagulant that preserves clotting factors for coagulation testing. The 9:1 blood-to-anticoagulant ratio is critical for accurate results.
A urine dipstick shows a positive nitrite result. This finding most likely indicates the presence of:
Answer: Gram-negative bacteria
Many gram-negative bacteria (e.g., E. coli) convert dietary nitrates to nitrites via reductase enzymes. A positive nitrite result strongly suggests a urinary tract infection caused by gram-negative organisms.
Which of the following white blood cell types is the FIRST to respond to an acute bacterial infection?
Answer: Neutrophils
Neutrophils are the primary first-responders in acute bacterial infections. They are phagocytic cells that rapidly migrate to sites of infection, and a left shift (increase in band neutrophils) is a classic laboratory finding.
A blood specimen with a hemoglobin of 7.0 g/dL and a mean corpuscular volume (MCV) of 115 fL is most consistent with which type of anemia?
Answer: Megaloblastic anemia
Megaloblastic anemia is characterized by a markedly elevated MCV (macrocytosis, typically >100 fL) due to impaired DNA synthesis from vitamin B12 or folate deficiency, resulting in abnormally large red blood cells.
Which quality control rule is violated when two consecutive control values fall more than 2 standard deviations on the same side of the mean?
Answer: Westgard 2-2s rule
The Westgard 2-2s rule is a rejection rule triggered when two consecutive control measurements exceed 2 SD on the same side of the mean, suggesting a systematic error or bias in the analytical run.
A Gram stain of a sputum specimen reveals purple (violet) cocci in clusters. Which organism is most likely responsible?
Answer: Staphylococcus aureus
Staphylococcus aureus is a gram-positive coccus that characteristically arranges in grape-like clusters. It retains the crystal violet dye in the Gram stain process, appearing purple, distinguishing it from gram-negative organisms.