ASCP BOC Exam with Questions and
Correct Answers Latest 2025-2026
GRADED A+
Which enzyme catalyzes the conversion of starch to glucose and maltose? - CORRECT
ANSWERS Amylase
Nephelometers measure light: - CORRECT ANSWERS Scattered at a right angle to the
light path
A serum sample demonstrates an elevated result when tested with the Jaffe reaction. This
indicates: - CORRECT ANSWERS Renal functional impairment
A vaginal/rectal swab is collected from a pregnant patient to screen for group B
Streptococcus colonization. What is the best medium to use for specimen inoculation? -
CORRECT ANSWERS Lim Broth
When testing a patient for HIV antibody, what is used to confirm a positive screening test? -
CORRECT ANSWERS Western Blot
An isolate from a stool culture gives the following growth characteristics and biochemical
reactions:
MAC: Colorless colonies
HE agar: Yellow-Orange colonies
TSI: Acid slant/acid butt, no gas, no h2s
Urea: Positive
These screening results are consistent with which enteric pathogen? - CORRECT
ANSWERS Yersinia entercolitica. Yersinia produces yellow colonies on HE because it can
ferment sucrose.
,When stool examination is negative, the preferred specimen for the diagnosis of
paragonimiasis is: - CORRECT ANSWERS Sputum. Paragonimus worms live in cystic
cavities in the lungs. Ova may be found in sputum, or swallowed and passed in stool.
A branching gram-positive, partially acid-fast organism is isolated from a bronchial
washing on a 63-year-old woman receiving chemotherapy. The organism does not
hydrolyze casein, tyrosine or xanthine. The most likely identification is: - CORRECT
ANSWERS Nocardia asteroides. (THINK BECAUSE OF THE BRANCHING). It is partially
acid fast and does not hydrolyze the substrates casein, tyrosine, or xanthine.
Use of only male donors as a source of plasma intended for transfusion is advocated to
reduce which type of reaction? - CORRECT ANSWERS TRALI. TRALI is most commonly
caused by donor HLA or granulocyte-specific antibodies that react with recipient antigens,
causing damage to the lung basement membrane and bilateral pulmonary edema within 6
hours of transfusion. Multiparous females are more likely to have antibodies than males.
Using male donors as the sole source of plasma products is a strategy for reducing the risk
of TRALI.
The result of an anti-nuclear antibody test was a titer of 1:320 with a peripheral pattern.
What best correlates with these results? - CORRECT ANSWERS Anti-dsDNA Titer 1:80.
and a high titer of antibodies to Sm. Peripheral pattern reacts with the antigenic
determinants of double strandedness of DNA.
Abnormalities found in erythroleukemia include: - CORRECT ANSWERS Megaloblastoid
development.
Which factor will not interfere with the reagent strip test for leukocytes in urine? -
CORRECT ANSWERS Nitrite. Nitrite is produced by bacteria, and WBCs are found when
there is a bacterial infection. If nitrite interfered with the WBC reaction, then the dipstick
would be worthless when testing patients with UTIs.
Which locus is used to identify the gender of the individual from whom a DNA sample is
obtained? - CORRECT ANSWERS Amelogenin. Amelogenin gives different sized
amplicons based on whether it is amplified from the X or Y chromosomes, so males would
have 2 bands on a gel at the amelogenin locus, while females would have only 1.
Penicillium species is isolated from a bone marrow culture of a patient that travelled to
southeast Asia. After 7 days the isolate produces a red pigment that diffuses into the
medium. The technologist should: - CORRECT ANSWERS Transfer a colony to BHI at 35
degrees. C. Penicillium marneffiei is a dimorphic fungi that produces a diffusible red
pigment.
,An elevated serum iron with normal iron binding capacity is most likely associated with: -
CORRECT ANSWERS Pernicious anemia. Ineffective erythropoiesis. High iron turnover.
Which enzyme substrate is the most specific for prostatic acid phosphatase for
quantitative endpoint reactions? - CORRECT ANSWERS Thymolphthalein
monophosphate. Thymolphthalein monophosphate is the most specific substrate of
choice for quantitative endpoint reactions; however, p-nitrophenylphosphate is the
preferred substrate for continuous monitoring.
The principle of the tablet test for bilirubin in urine or feces is: - CORRECT ANSWERS
Chemical coupling of bilirubin with a diazonium salt to form a purple color.
Ghost red blood cells are seen in urine that is: - CORRECT ANSWERS Alkaline and dilute.
RBCs absorb water when in dilute urine, and are also less preserved in alkaline urine.
Therefore, as the cells swell in the alkaline urine, the cell membrane allows hemoglobin to
leak from the cell, resulting in the empty cell membrane and the pale appearance.
In the cold agglutinin test, the tubes containing the serum and erythrocytes are allowed to
stand overnight in the refrigerator, and the results are read the next morning. If a disk of the
erythrocytes floats up from the bottom of the tube with only the flick of finger, this is read as
a: - CORRECT ANSWERS A 4+ reaction. When one solid agglutinate is present, the
reaction is classified as 4+.
A bone marrow shows foam cells ranging from 20-100 μm in size, vacuolated cytoplasm
containing sphingomyelin and is faintly PAS+. This cell type is most characteristic of: -
CORRECT ANSWERS Niemann-Pick Disease
The presence of leukocytes in urine is known as: - CORRECT ANSWERS Pyuria
In what metabolic disease will urine turn dark brown to black upon standing? - CORRECT
ANSWERS Alkaptonuria
First-generation cephalosporins can be adequately represented by: - CORRECT
ANSWERS Cephalothin
According to AABB Standards, Platelets prepared from Whole Blood shall have at least: -
CORRECT ANSWERS 5.5x10^10 platelets per unit in at least 90% of the units tested
A stool specimen that appears black and tarry should be tested for the presence of: -
CORRECT ANSWERS Occult blood
, Sodium bicarbonate and sodium citrate are components of which of the following? -
CORRECT ANSWERS JEMBEC system. The JEMBEC system is a transport and
inoculation medium used for direct plating of specimens for N gonorrhoeae. Chocolate
based selective medium is inoculated with the specimen. This is placed in an impermeable
plastic bag with a bicarbonatesodium citrate pellet that absorbs moisture to generate a
carbon dioxide-rich environment.
A 44-year-old man was admitted to the hospital following a 2-week history of low-grade
fever, malaise and anorexia. Examination of a Giemsa stain revealed many
intraerythrocytic parasites. Further history revealed frequent camping trips near Martha's
Vineyard and Nantucket Island, but no travel outside the continental United States. This
parasite could easily be confused with: - CORRECT ANSWERS Plasmodium falciparum.
The patient's history is suggestive of Babesia infection. Babesia microti ring forms are
similar to Plasmodium falciparum. A travel history is helpful in determining the cause of
infection.
Platelets prepared in a polyolefin type container, stored at 22° - 24°C in 50 mL of plasma,
and gently agitated can be used for up to: - CORRECT ANSWERS 5 days.
A 29-year-old man is seen for recurrence of a purulent urethral discharge 10 days after the
successful treatment of culture proven gonorrhea. The most likely etiology of his urethritis
is: - CORRECT ANSWERS Chlamydia trachomatis. Up to 1/3 of patients with Neisseria
gonorrhoeae infection are also coinfected with Chlamydia trachomatis. Patients with
identified infection with one organism are usually treated for both infections.
The (8;14) chromosomal translocation brings which of the following 2 genes in close
proximity? - CORRECT ANSWERS C-myc and the immunoglobulin heavy chain. The
t(8;14) typically found in Burkitt leukemia (ALL-L3), brings the master cell cycle control
factor c-myc on chromosome 8 under the influence of the strong immunoglobulin heavy
chain promoter on chromosome 14, driving a leukemogenic process.
The technologist observes apparent homogenous staining of the nucleus of interphase
cells while performing an IFA-ANA, as well as staining of the chromosomes in mitotic cells.
This result is: - CORRECT ANSWERS Expected for anti-DNA antibodies.
An AFB broth culture is positive for acid-fast bacilli at 1 week while the agar slant shows no
growth. The most likely explanation for this is: - CORRECT ANSWERS AFB grow more
rapidly in liquid media.
Correct Answers Latest 2025-2026
GRADED A+
Which enzyme catalyzes the conversion of starch to glucose and maltose? - CORRECT
ANSWERS Amylase
Nephelometers measure light: - CORRECT ANSWERS Scattered at a right angle to the
light path
A serum sample demonstrates an elevated result when tested with the Jaffe reaction. This
indicates: - CORRECT ANSWERS Renal functional impairment
A vaginal/rectal swab is collected from a pregnant patient to screen for group B
Streptococcus colonization. What is the best medium to use for specimen inoculation? -
CORRECT ANSWERS Lim Broth
When testing a patient for HIV antibody, what is used to confirm a positive screening test? -
CORRECT ANSWERS Western Blot
An isolate from a stool culture gives the following growth characteristics and biochemical
reactions:
MAC: Colorless colonies
HE agar: Yellow-Orange colonies
TSI: Acid slant/acid butt, no gas, no h2s
Urea: Positive
These screening results are consistent with which enteric pathogen? - CORRECT
ANSWERS Yersinia entercolitica. Yersinia produces yellow colonies on HE because it can
ferment sucrose.
,When stool examination is negative, the preferred specimen for the diagnosis of
paragonimiasis is: - CORRECT ANSWERS Sputum. Paragonimus worms live in cystic
cavities in the lungs. Ova may be found in sputum, or swallowed and passed in stool.
A branching gram-positive, partially acid-fast organism is isolated from a bronchial
washing on a 63-year-old woman receiving chemotherapy. The organism does not
hydrolyze casein, tyrosine or xanthine. The most likely identification is: - CORRECT
ANSWERS Nocardia asteroides. (THINK BECAUSE OF THE BRANCHING). It is partially
acid fast and does not hydrolyze the substrates casein, tyrosine, or xanthine.
Use of only male donors as a source of plasma intended for transfusion is advocated to
reduce which type of reaction? - CORRECT ANSWERS TRALI. TRALI is most commonly
caused by donor HLA or granulocyte-specific antibodies that react with recipient antigens,
causing damage to the lung basement membrane and bilateral pulmonary edema within 6
hours of transfusion. Multiparous females are more likely to have antibodies than males.
Using male donors as the sole source of plasma products is a strategy for reducing the risk
of TRALI.
The result of an anti-nuclear antibody test was a titer of 1:320 with a peripheral pattern.
What best correlates with these results? - CORRECT ANSWERS Anti-dsDNA Titer 1:80.
and a high titer of antibodies to Sm. Peripheral pattern reacts with the antigenic
determinants of double strandedness of DNA.
Abnormalities found in erythroleukemia include: - CORRECT ANSWERS Megaloblastoid
development.
Which factor will not interfere with the reagent strip test for leukocytes in urine? -
CORRECT ANSWERS Nitrite. Nitrite is produced by bacteria, and WBCs are found when
there is a bacterial infection. If nitrite interfered with the WBC reaction, then the dipstick
would be worthless when testing patients with UTIs.
Which locus is used to identify the gender of the individual from whom a DNA sample is
obtained? - CORRECT ANSWERS Amelogenin. Amelogenin gives different sized
amplicons based on whether it is amplified from the X or Y chromosomes, so males would
have 2 bands on a gel at the amelogenin locus, while females would have only 1.
Penicillium species is isolated from a bone marrow culture of a patient that travelled to
southeast Asia. After 7 days the isolate produces a red pigment that diffuses into the
medium. The technologist should: - CORRECT ANSWERS Transfer a colony to BHI at 35
degrees. C. Penicillium marneffiei is a dimorphic fungi that produces a diffusible red
pigment.
,An elevated serum iron with normal iron binding capacity is most likely associated with: -
CORRECT ANSWERS Pernicious anemia. Ineffective erythropoiesis. High iron turnover.
Which enzyme substrate is the most specific for prostatic acid phosphatase for
quantitative endpoint reactions? - CORRECT ANSWERS Thymolphthalein
monophosphate. Thymolphthalein monophosphate is the most specific substrate of
choice for quantitative endpoint reactions; however, p-nitrophenylphosphate is the
preferred substrate for continuous monitoring.
The principle of the tablet test for bilirubin in urine or feces is: - CORRECT ANSWERS
Chemical coupling of bilirubin with a diazonium salt to form a purple color.
Ghost red blood cells are seen in urine that is: - CORRECT ANSWERS Alkaline and dilute.
RBCs absorb water when in dilute urine, and are also less preserved in alkaline urine.
Therefore, as the cells swell in the alkaline urine, the cell membrane allows hemoglobin to
leak from the cell, resulting in the empty cell membrane and the pale appearance.
In the cold agglutinin test, the tubes containing the serum and erythrocytes are allowed to
stand overnight in the refrigerator, and the results are read the next morning. If a disk of the
erythrocytes floats up from the bottom of the tube with only the flick of finger, this is read as
a: - CORRECT ANSWERS A 4+ reaction. When one solid agglutinate is present, the
reaction is classified as 4+.
A bone marrow shows foam cells ranging from 20-100 μm in size, vacuolated cytoplasm
containing sphingomyelin and is faintly PAS+. This cell type is most characteristic of: -
CORRECT ANSWERS Niemann-Pick Disease
The presence of leukocytes in urine is known as: - CORRECT ANSWERS Pyuria
In what metabolic disease will urine turn dark brown to black upon standing? - CORRECT
ANSWERS Alkaptonuria
First-generation cephalosporins can be adequately represented by: - CORRECT
ANSWERS Cephalothin
According to AABB Standards, Platelets prepared from Whole Blood shall have at least: -
CORRECT ANSWERS 5.5x10^10 platelets per unit in at least 90% of the units tested
A stool specimen that appears black and tarry should be tested for the presence of: -
CORRECT ANSWERS Occult blood
, Sodium bicarbonate and sodium citrate are components of which of the following? -
CORRECT ANSWERS JEMBEC system. The JEMBEC system is a transport and
inoculation medium used for direct plating of specimens for N gonorrhoeae. Chocolate
based selective medium is inoculated with the specimen. This is placed in an impermeable
plastic bag with a bicarbonatesodium citrate pellet that absorbs moisture to generate a
carbon dioxide-rich environment.
A 44-year-old man was admitted to the hospital following a 2-week history of low-grade
fever, malaise and anorexia. Examination of a Giemsa stain revealed many
intraerythrocytic parasites. Further history revealed frequent camping trips near Martha's
Vineyard and Nantucket Island, but no travel outside the continental United States. This
parasite could easily be confused with: - CORRECT ANSWERS Plasmodium falciparum.
The patient's history is suggestive of Babesia infection. Babesia microti ring forms are
similar to Plasmodium falciparum. A travel history is helpful in determining the cause of
infection.
Platelets prepared in a polyolefin type container, stored at 22° - 24°C in 50 mL of plasma,
and gently agitated can be used for up to: - CORRECT ANSWERS 5 days.
A 29-year-old man is seen for recurrence of a purulent urethral discharge 10 days after the
successful treatment of culture proven gonorrhea. The most likely etiology of his urethritis
is: - CORRECT ANSWERS Chlamydia trachomatis. Up to 1/3 of patients with Neisseria
gonorrhoeae infection are also coinfected with Chlamydia trachomatis. Patients with
identified infection with one organism are usually treated for both infections.
The (8;14) chromosomal translocation brings which of the following 2 genes in close
proximity? - CORRECT ANSWERS C-myc and the immunoglobulin heavy chain. The
t(8;14) typically found in Burkitt leukemia (ALL-L3), brings the master cell cycle control
factor c-myc on chromosome 8 under the influence of the strong immunoglobulin heavy
chain promoter on chromosome 14, driving a leukemogenic process.
The technologist observes apparent homogenous staining of the nucleus of interphase
cells while performing an IFA-ANA, as well as staining of the chromosomes in mitotic cells.
This result is: - CORRECT ANSWERS Expected for anti-DNA antibodies.
An AFB broth culture is positive for acid-fast bacilli at 1 week while the agar slant shows no
growth. The most likely explanation for this is: - CORRECT ANSWERS AFB grow more
rapidly in liquid media.
