ASCP MLS questions and answers 2025\2026
A+ Grade
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
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
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
A+ Grade
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
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
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
