ESTUDYR
ASCP CG CERTIFICATION PRACTICE QUESTIONS AND CORRECT DETAILED
ANSWERS (VERIFIED ANSWERS) | ASSURED SUCCESS
What is the best agent to use against Mycoplasma contamination in cell cultures?
A. Penicillin–Streptomycin
B. BM Cyclin (tiamulin + minocycline)
C. Amphotericin B
D. Gentamicin
Rationale: BM Cyclin combines tiamulin and minocycline, which effectively inhibit Mycoplasma growth
without harming mammalian cells.
For successful harvest, each new batch of hypotonic solution should be validated by:
A. Checking pH only
B. Comparing the new lot to a previously validated lot
C. Measuring osmolality against a standard chart
D. Verifying color change on addition of cells
Rationale: Direct comparison with a known good lot ensures the hypotonic solution performs identically
in lysing red cells.
Collagenase, pronase, and trypsin are all examples of:
A. Nucleases
B. Lipases
C. Proteolytic enzymes
D. Glycosidases
Rationale: These enzymes digest proteins, facilitating the breakdown of tissue into single‐cell
suspensions.
After adding Colcemid to peripheral blood cultures, aseptic technique is no longer critical because:
A. Colcemid sterilizes the culture
B. Cells become resistant to contamination
C. Colcemid halts cells at metaphase and prevents further division
D. Antibiotics are automatically released
Rationale: Colcemid arrests cells in metaphase; additional divisions cease, reducing the impact of minor
contamination on cytogenetic spreads.
Upon sample arrival in the cytogenetics lab, the first step is to:
A. Begin cell culture immediately
B. Log the specimen into the system
C. Centrifuge to pellet cells
D. Fix cells in methanol
Rationale: Accurate logging ensures traceability and proper identification throughout analysis.
,ESTUDYR
Phytohemagglutinin (PHA) is used to stimulate division of:
A. B lymphocytes
B. Neutrophils
C. T lymphocytes
D. Monocytes
Rationale: PHA is a mitogen that specifically activates T‐cell proliferation in culture.
When documenting a culture failure, the MOST critical information to record is the:
A. Operator’s name
B. Culture start time
C. Expiration dates of reagents used
D. Incubator door open frequency
Rationale: Expired reagents are a common cause of culture failure and should be tracked for QC.
Which type of microscope is most appropriate for cleaning a chorionic villus sampling (CVS)
specimen?
A. Phase contrast
B. Electron microscope
C. Dissection (stereoscopic) microscope
D. Confocal microscope
Rationale: A dissection scope provides low‐magnification, three‐dimensional view for manual removal
of maternal tissue.
The most problematic contaminant cell type in a CVS sample is:
A. Trophoblasts
B. Mesenchymal cells
C. Syncytiotrophoblasts
D. Decidual cells (maternal tissue)
Rationale: Maternal decidua, if not removed, can lead to misleading maternal karyotypes.
Under phase contrast after dropping cells, excessive cytoplasm around metaphases likely indicates:
A. Too high hypotonic concentration
B. Overdigested enzymes
C. Inappropriate slide drying time
D. Wrong stain
Rationale: Rapid or uneven drying leaves excess cytoplasm; adjusting drying time improves spread
quality.
What practice best prevents microbial and cross‐contamination of cell cultures?
A. High humidity
B. Strict aseptic technique
C. Lowering incubator temperature
,ESTUDYR
D. Open bench work
Rationale: Aseptic technique (sterile tools, proper BSC use) is essential to maintain culture integrity.
If initial metaphase yield is insufficient, the next step is to:
A. Discard the sample
B. Increase Colcemid concentration
C. Prepare additional slides from remaining sample
D. Switch to a different enzyme
Rationale: Maximizing use of existing culture by making more drops can increase chromosome yields.
Sparse, over‐spread metaphases on a dropped slide can be corrected by:
A. Decreasing hypotonic time
B. Increasing slide drying time (e.g., warm slides)
C. Adding more fixative
D. Shortening Colcemid treatment
Rationale: Longer drying allows proper chromosome adherence and compact spreads.
Which statement is true of an inverted microscope?
A. Objectives are above the stage
B. It cannot view live cultures
C. Objectives are beneath the stage
D. It is only used for pathology
Rationale: Inverted scopes allow viewing through the bottom of culture flasks, ideal for live cell
observation.
High‐resolution banding is indicated when suspecting:
A. Down syndrome
B. Turner syndrome
C. DiGeorge syndrome (22q11 microdeletion)
D. Trisomy 21 mosaicism
Rationale: High‐res banding reveals small microdeletions such as those in DiGeorge/velocardiofacial
syndrome.
When verifying specimen appropriateness for cytogenetics, the MOST critical accompanying
information is the:
A. Patient’s weight
B. Time of day
C. Reason for referral (clinical indication)
D. Technician name
Rationale: Clinical context guides protocol choice, culture conditions, and interpretation of results.
For Turner syndrome cytogenetic analysis, the preferred specimen is:
A. Skin biopsy
B. Heparinized peripheral blood at room temperature
, ESTUDYR
C. Frozen amniotic fluid
D. Urine sediment
Rationale: Heparinized blood preserves lymphocytes for culture; freezing damages cells.
A blood sample can be used to study malignancy karyotypes only if:
A. Monocytes are abundant
B. Serum is removed
C. Circulating malignant cells are present and dividing
D. Platelets are low
Rationale: Leukemic blasts must be in circulation and mitotically active for successful tumor
cytogenetics.
If all cultures in a CO₂ incubator fail, monitor the incubator’s:
A. Light intensity
B. O₂ level
C. Temperature, CO₂ level, and humidity
D. Noise level
Rationale: Proper temperature, CO₂ concentration, and humidity are critical to cell growth; deviations
can cause failures.
The single most important factor affecting chromosome quality under phase contrast is:
A. Enzyme concentration
B. Slide flick technique
C. Colcemid timing
D. Slide drying after dropping cells
Rationale: Controlled drying ensures optimal chromosome spreading and morphology.
Which test compares variance among groups while controlling for a covariate?
A. Factorial ANOVA
B. ANCOVA
C. MANOVA
D. Paired t‐test
Rationale: ANCOVA adjusts for continuous covariates when comparing group means.
Which test is used for ordinal data relationships?
A. Pearson correlation
B. Spearman rank correlation
C. Independent t‐test
D. Chi‐Square test
Rationale: Spearman’s rho measures monotonic relationships between ranked variables.
Which statistical test would analyze pre‐, mid‐, and post‐treatment measures in one group?
A. One‐way ANOVA
B. Paired t‐test
ASCP CG CERTIFICATION PRACTICE QUESTIONS AND CORRECT DETAILED
ANSWERS (VERIFIED ANSWERS) | ASSURED SUCCESS
What is the best agent to use against Mycoplasma contamination in cell cultures?
A. Penicillin–Streptomycin
B. BM Cyclin (tiamulin + minocycline)
C. Amphotericin B
D. Gentamicin
Rationale: BM Cyclin combines tiamulin and minocycline, which effectively inhibit Mycoplasma growth
without harming mammalian cells.
For successful harvest, each new batch of hypotonic solution should be validated by:
A. Checking pH only
B. Comparing the new lot to a previously validated lot
C. Measuring osmolality against a standard chart
D. Verifying color change on addition of cells
Rationale: Direct comparison with a known good lot ensures the hypotonic solution performs identically
in lysing red cells.
Collagenase, pronase, and trypsin are all examples of:
A. Nucleases
B. Lipases
C. Proteolytic enzymes
D. Glycosidases
Rationale: These enzymes digest proteins, facilitating the breakdown of tissue into single‐cell
suspensions.
After adding Colcemid to peripheral blood cultures, aseptic technique is no longer critical because:
A. Colcemid sterilizes the culture
B. Cells become resistant to contamination
C. Colcemid halts cells at metaphase and prevents further division
D. Antibiotics are automatically released
Rationale: Colcemid arrests cells in metaphase; additional divisions cease, reducing the impact of minor
contamination on cytogenetic spreads.
Upon sample arrival in the cytogenetics lab, the first step is to:
A. Begin cell culture immediately
B. Log the specimen into the system
C. Centrifuge to pellet cells
D. Fix cells in methanol
Rationale: Accurate logging ensures traceability and proper identification throughout analysis.
,ESTUDYR
Phytohemagglutinin (PHA) is used to stimulate division of:
A. B lymphocytes
B. Neutrophils
C. T lymphocytes
D. Monocytes
Rationale: PHA is a mitogen that specifically activates T‐cell proliferation in culture.
When documenting a culture failure, the MOST critical information to record is the:
A. Operator’s name
B. Culture start time
C. Expiration dates of reagents used
D. Incubator door open frequency
Rationale: Expired reagents are a common cause of culture failure and should be tracked for QC.
Which type of microscope is most appropriate for cleaning a chorionic villus sampling (CVS)
specimen?
A. Phase contrast
B. Electron microscope
C. Dissection (stereoscopic) microscope
D. Confocal microscope
Rationale: A dissection scope provides low‐magnification, three‐dimensional view for manual removal
of maternal tissue.
The most problematic contaminant cell type in a CVS sample is:
A. Trophoblasts
B. Mesenchymal cells
C. Syncytiotrophoblasts
D. Decidual cells (maternal tissue)
Rationale: Maternal decidua, if not removed, can lead to misleading maternal karyotypes.
Under phase contrast after dropping cells, excessive cytoplasm around metaphases likely indicates:
A. Too high hypotonic concentration
B. Overdigested enzymes
C. Inappropriate slide drying time
D. Wrong stain
Rationale: Rapid or uneven drying leaves excess cytoplasm; adjusting drying time improves spread
quality.
What practice best prevents microbial and cross‐contamination of cell cultures?
A. High humidity
B. Strict aseptic technique
C. Lowering incubator temperature
,ESTUDYR
D. Open bench work
Rationale: Aseptic technique (sterile tools, proper BSC use) is essential to maintain culture integrity.
If initial metaphase yield is insufficient, the next step is to:
A. Discard the sample
B. Increase Colcemid concentration
C. Prepare additional slides from remaining sample
D. Switch to a different enzyme
Rationale: Maximizing use of existing culture by making more drops can increase chromosome yields.
Sparse, over‐spread metaphases on a dropped slide can be corrected by:
A. Decreasing hypotonic time
B. Increasing slide drying time (e.g., warm slides)
C. Adding more fixative
D. Shortening Colcemid treatment
Rationale: Longer drying allows proper chromosome adherence and compact spreads.
Which statement is true of an inverted microscope?
A. Objectives are above the stage
B. It cannot view live cultures
C. Objectives are beneath the stage
D. It is only used for pathology
Rationale: Inverted scopes allow viewing through the bottom of culture flasks, ideal for live cell
observation.
High‐resolution banding is indicated when suspecting:
A. Down syndrome
B. Turner syndrome
C. DiGeorge syndrome (22q11 microdeletion)
D. Trisomy 21 mosaicism
Rationale: High‐res banding reveals small microdeletions such as those in DiGeorge/velocardiofacial
syndrome.
When verifying specimen appropriateness for cytogenetics, the MOST critical accompanying
information is the:
A. Patient’s weight
B. Time of day
C. Reason for referral (clinical indication)
D. Technician name
Rationale: Clinical context guides protocol choice, culture conditions, and interpretation of results.
For Turner syndrome cytogenetic analysis, the preferred specimen is:
A. Skin biopsy
B. Heparinized peripheral blood at room temperature
, ESTUDYR
C. Frozen amniotic fluid
D. Urine sediment
Rationale: Heparinized blood preserves lymphocytes for culture; freezing damages cells.
A blood sample can be used to study malignancy karyotypes only if:
A. Monocytes are abundant
B. Serum is removed
C. Circulating malignant cells are present and dividing
D. Platelets are low
Rationale: Leukemic blasts must be in circulation and mitotically active for successful tumor
cytogenetics.
If all cultures in a CO₂ incubator fail, monitor the incubator’s:
A. Light intensity
B. O₂ level
C. Temperature, CO₂ level, and humidity
D. Noise level
Rationale: Proper temperature, CO₂ concentration, and humidity are critical to cell growth; deviations
can cause failures.
The single most important factor affecting chromosome quality under phase contrast is:
A. Enzyme concentration
B. Slide flick technique
C. Colcemid timing
D. Slide drying after dropping cells
Rationale: Controlled drying ensures optimal chromosome spreading and morphology.
Which test compares variance among groups while controlling for a covariate?
A. Factorial ANOVA
B. ANCOVA
C. MANOVA
D. Paired t‐test
Rationale: ANCOVA adjusts for continuous covariates when comparing group means.
Which test is used for ordinal data relationships?
A. Pearson correlation
B. Spearman rank correlation
C. Independent t‐test
D. Chi‐Square test
Rationale: Spearman’s rho measures monotonic relationships between ranked variables.
Which statistical test would analyze pre‐, mid‐, and post‐treatment measures in one group?
A. One‐way ANOVA
B. Paired t‐test
