CORRECT ACTUAL QUESTIONS AND
CORRECTLY WELL DEFINED ANSWERS
LATEST ALREADY GRADED A+ 2025 – 2026
Which is the worst type of culture failure?
no PHA added to blood media
how to interpret chromosome microarray analysis (SNP
microarray)
chromosome microarray can
identify mosaicism
identify uniparental disomy
identify consanguinity
chromosome microarray can not
find any translocation
deletion on chromosome microarray graph (more green
than red)
data points closer to the -1 axis
duplication on chromosome microarray graph (more red
than green)
,data points closer to the +1 axis
normal chromosome microarray graph (green and red
spread evenly)
data points align at or near the 0 axis
limitations of chromosome microarray analysis
- relatively expensive
- not informative for balanced rearrangements and polyploidy
- the detection of copy number variations of uncertain
significance is challenging
- difficult to detect small subclones (~30% of sample or less)
SNP array can
detect heterozygosity
Koehler illumination procedure
- focus on low power objective
- close field diaphragm completely
- rack condenser up/down til edges are in focus
- center the image
- reopen field diaphragm
- set condenser via removing eyepiece and adjusting until
light fills objective lens 2/3 to 3/4
All of the following are factors which affect the
cryopreservation except
,A fast growing culture shows signs of cell death. What is a
possible reason for this?
cell confluency: too many or too few cells
collagenase, pronase, and trypsin are used to disperse tissue
into single-cell suspension. These substances are:
proteolytic enzymes
When harvesting peripheral blood cultures, asceptic
technique no longer matters following incubation with:
colcemid
Which of the following culture processes would be most
useful for identifying patients w/ fanconi anemia?
mitomycin-C stress test of peripheral blood
To avoid potential culture failure, it is important to monitor
the reagents used. Recording which of the following
information will be most important when documenting
culture failure?
expiration date
The morning after being set-up, a single dish of amniotic
fluid culture turns cloudy and appears contaminated. None
of the other cultures set up that day appear contaminated.
Which of the following should be done first?
harvest the culture as soon as possible
, If an amniotic fluid culture from the same sample grows
well in a different incubator, the probable cause of the
culture failure is
incubator failure
Positive staining w/ Hoechst 33258 reveals micronuclei.
Which of the following agents caused the culture
contamination?
mycoplasma
Which of the following statements is true about trypsin>
is is useful in removing cells from culture flasks
Which of the following is the best tissue to use for both a
good success rate and abnormality detection in
spontaneous abortion specimen
chorionic villi
When a culture becomes contaminated, the culture medium
shifts to an acidic pH. If the medium contains a pH indicator,
the color of the medium in the flask will appear
yellow
Which of the following reagents is used in culturing
peripheral blood, but not in culturing bone marrow or
amniotic fluid or chromosome analysis?
phytohemagglutinin (PHA)