ASCP MLS EXAM QUESTIONS AND
ANSWERS 2025
What feature is most often found with patients with a splenectomy on a Wright's
stained blood smear? -Correct Answer ✔Howell-Jolly bodies
Patients with antibody to the following antigen are immune to Hepatitis B: -
Correct Answer ✔Surface antigen (HbSAg)
Which two of the following tests are helpful for documenting previous
Streptococcal throat and skin infections: -Correct Answer ✔ASO titer and Anti-
DNase B
In mass spectrometry, the "appearance potential" is defined as the: -Correct
Answer ✔Minimum energy required for the appearance of a particular fragment
ion in mass spectrum
What is generally accepted as the lower threshold value for semen pH from fertile
males? -Correct Answer ✔7.2
Coulometry: -Correct Answer ✔An automated method for measuring chloride
which generates silver ions in the reaction
Erythroleukemia: -Correct Answer ✔Also known as Acute Myelogenous
Leukemia type M6. This type is associated with either the presence of both
erythroid and myeloid precursors OR strictly erythroid precursors.
Myelomonocytic leukemia -Correct Answer ✔Is associated with an increase in
myeloid and monocytic cell precursors, but not red blood cell precursors
Species that are Lysine (+), arginine (=) and ornithine (+): -Correct Answer
✔Enterobacter aerogenes, Edwardsiella species and most Serratia species
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Lysine reaction for all Citrobacter: -Correct Answer ✔Negative
Key identifying characteristic for Pantoa (Enterobacter) agglomerans: -Correct
Answer ✔negative reactions for the three decarboxylases commonly tested (
Lysine, arginine and ornithine)
Which organism is MOST likely responsible for septic reactions associated with
Red Blood Cell transfusions? -Correct Answer ✔Yersina entercolitica is most
likely responsible for septic reactions in transfusions of Red Blood Cells. This
organism is usually acquired by ingestion of contaminated food and causes mild
symptoms of abdominal pain and diarrhea. Growth of Y. entercolitica is enhanced
in iron-rich environments such as red cell components.
Gaucher's disease -Correct Answer ✔The most common lysosomal storage disease
caused by insufficient activity of the lysosomal enzyme glucocerebrosidase that
leads to the deposition of glucocerebroside in cells of the macrophage-monocyte
system.
Diseases associated with dysfunctions of polymorphonuclear neutrophils (PMNs) -
Correct Answer ✔Chediak-Higashi syndrome (CH), Chronic granulomatous
disease (CGD), Myeloperoxidase deficiency (MPO)
Nephrotic Syndrome: -Correct Answer ✔Caused by damage to the kidneys,
especially the basement membrane of the glomerulus; which causes abnormal
excretion of protein and red blood cells in the urine. Fats are also present in the
urine in most cases. A foamy appearance of the urine is a key characteristic of this
condition.
Clinical symptoms include:
Swelling
Weight gain from fluid retention
Poor appetite
High blood pressure
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Key Biochemical reactions for Enterobacteriaceae: -Correct Answer ✔The key
biochemical reactions by which the family Enterobacteriaceae can be identified
include fermentation of carbohydrates, reduction of nitrates to nitrites and the
absence of cytochrome oxidase activity.
ANA -Correct Answer ✔See 2 quiz #27
Prozone effect: -Correct Answer ✔Results in a false positive reaction; is the result
of antibody excess and dilution of antibody can help prevent its occurrence
Purpose of a bi-chromatic analyzer with dual wavelengths is: -Correct Answer
✔Minimize the effect of interference
Key characteristics of Micrococcus: -Correct Answer ✔Susceptible to bacitracin
("A") and resistant to furazolidone; gram positive cocci in tetras, bacteria cells of
micrococcus luteus are larger than those of the staphylococci and can arrange in
tetras
What is the glomerular filtration rate for a patient with a serum creatinine of 2
mg/dL, if the urine creatinine was 124 mg/dL and the urine volume was 2.2 L/24
hrs? -Correct Answer ✔95 mL/min
One method of calculating a glomerular filtration rate is using creatinine and urine
volume to determine creatinine clearance. The equation is as follows:
Creatinine Clearance = (urine creatinine X urine flow rate) / plasma creatinine;
where urine flow rate = volume in mL /24 hours x h/60 min)
In this case = creatinine clearance = 124 X (2200/24 x hour/60) / 2 = 94.7 or 95
ml/min
Estrogen and progesterone markers are most commonly used to provide prognostic
information about: -Correct Answer ✔Breast cancer
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