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Exam Prep

Histopathology & Cytology practice questions.

Fixation, processing, microtomy, staining, immunohistochemistry, cytology and lab safety.

All subjects

Independent practice questions written by Labologics. Not affiliated with DHA, DOH (formerly HAAD), SCFHS, Prometric or any exam body. Not recalled exam questions.

Fixation

Q1 Fixation · Easy

The most widely used routine fixative in histopathology is:

  1. A: 10% neutral buffered formalin
  2. B: Glacial acetic acid
  3. C: Picric acid
  4. D: Absolute alcohol
Show answer

Answer: A — 10% neutral buffered formalin

10% NBF is about 4% formaldehyde. It fixes by forming methylene cross-links between proteins.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q2 Fixation · Medium

The recommended volume of fixative relative to tissue is about:

  1. A: 1:1
  2. B: 10-20 times the tissue volume
  3. C: 2 times
  4. D: 100 times
Show answer

Answer: B — 10-20 times the tissue volume

Formalin penetrates about 1 mm per hour, so tissue slices should be thin (3-5 mm).

Reference: Bancroft's Theory and Practice of Histological Techniques

Q3 Fixation · Medium

Brown-black birefringent granules in tissue fixed in acidic (unbuffered) formalin are:

  1. A: Carbon
  2. B: Melanin
  3. C: Formalin (acid formaldehyde hematin) pigment
  4. D: Hemosiderin
Show answer

Answer: C — Formalin (acid formaldehyde hematin) pigment

It is prevented by using buffered formalin and removed with alcoholic picric acid.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q4 Fixation · Medium

Bouin's solution contains:

  1. A: Osmium tetroxide
  2. B: Glutaraldehyde
  3. C: Mercuric chloride
  4. D: Picric acid, formalin and acetic acid
Show answer

Answer: D — Picric acid, formalin and acetic acid

It is used for testis and some biopsies. Glutaraldehyde (with osmium post-fixation) is used for electron microscopy.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q5 Fixation · Easy

Papanicolaou-stained smears must be:

  1. A: Wet-fixed immediately in 95% ethanol (or spray fixative)
  2. B: Heat-fixed
  3. C: Fixed in formalin vapor for 1 hour
  4. D: Air-dried
Show answer

Answer: A — Wet-fixed immediately in 95% ethanol (or spray fixative)

Air-dried smears are stained with Romanowsky stains such as Diff-Quik or May-Grunwald Giemsa.

Reference: Koss' Diagnostic Cytology

Processing

Q6 Processing · Easy

The correct order of tissue processing is:

  1. A: Clearing, dehydration, infiltration
  2. B: Fixation, dehydration, clearing, infiltration (embedding)
  3. C: Dehydration, fixation, clearing
  4. D: Embedding, fixation, clearing
Show answer

Answer: B — Fixation, dehydration, clearing, infiltration (embedding)

Paraffin does not mix with water or alcohol, so a clearing agent (e.g., xylene) is needed.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q7 Processing · Easy

The most common dehydrating agent is:

  1. A: Formalin
  2. B: Xylene
  3. C: Graded ethanol
  4. D: Paraffin
Show answer

Answer: C — Graded ethanol

Moving through increasing concentrations reduces shrinkage and distortion.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q8 Processing · Medium

Clearing agents such as xylene are used because they:

  1. A: Stain nuclei
  2. B: Decalcify bone
  3. C: Dehydrate tissue
  4. D: Are miscible with both alcohol and paraffin wax
Show answer

Answer: D — Are miscible with both alcohol and paraffin wax

Tissue looks transparent when cleared.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q9 Processing · Medium

Paraffin wax for embedding usually melts at about:

  1. A: 37 C
  2. B: 56-58 C
  3. C: 80 C
  4. D: 100 C
Show answer

Answer: B — 56-58 C

Overheated wax makes tissue hard and brittle.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q10 Processing · Medium

Which agent is used to decalcify bone while best preserving nucleic acids and antigens?

  1. A: Picric acid
  2. B: EDTA (chelating agent)
  3. C: Concentrated hydrochloric acid
  4. D: Xylene
Show answer

Answer: B — EDTA (chelating agent)

EDTA is slow but gentle. Strong acids (nitric, hydrochloric) and formic acid are faster but damage morphology and DNA.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q11 Processing · Medium

The end point of decalcification can be checked by:

  1. A: Color change to pink
  2. B: Smell
  3. C: X-ray or a chemical test for calcium (calcium oxalate test)
  4. D: Weight gain
Show answer

Answer: C — X-ray or a chemical test for calcium (calcium oxalate test)

Over-decalcification damages staining.

Reference: Bancroft's Theory and Practice of Histological Techniques

Microtomy & frozen sections

Q12 Microtomy & frozen sections · Easy

The usual section thickness for routine paraffin sections is:

  1. A: 0.1 micrometer
  2. B: 3-5 micrometers
  3. C: 20 micrometers
  4. D: 100 micrometers
Show answer

Answer: B — 3-5 micrometers

Ultrathin sections for electron microscopy are 60-90 nm.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q13 Microtomy & frozen sections · Medium

Horizontal 'venetian blind' (chatter) lines in sections are caused by:

  1. A: Vibration from a loose blade, block or overly hard tissue
  2. B: Poor fixation
  3. C: Air bubbles
  4. D: Dull knife
Show answer

Answer: A — Vibration from a loose blade, block or overly hard tissue

Tighten the blade and block and reduce cutting speed.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q14 Microtomy & frozen sections · Easy

Frozen sections are cut in a:

  1. A: Rotary microtome at room temperature
  2. B: Cryostat at about -20 C
  3. C: Ultramicrotome
  4. D: Sledge microtome
Show answer

Answer: B — Cryostat at about -20 C

Used for rapid intraoperative diagnosis and some enzyme and lipid studies.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q15 Microtomy & frozen sections · Medium

Ice crystal artifact (holes) in frozen sections is reduced by:

  1. A: Using warm OCT
  2. B: Slow freezing
  3. C: Rapid freezing (e.g., isopentane cooled in liquid nitrogen)
  4. D: Thawing and refreezing
Show answer

Answer: C — Rapid freezing (e.g., isopentane cooled in liquid nitrogen)

Slow freezing forms large ice crystals.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q16 Microtomy & frozen sections · Medium

Which tissue is most difficult to cut on a cryostat?

  1. A: Lymph node
  2. B: Kidney
  3. C: Liver
  4. D: Fatty tissue (e.g., breast fat)
Show answer

Answer: D — Fatty tissue (e.g., breast fat)

Fat does not freeze well at standard cryostat temperatures; colder settings are needed.

Reference: Bancroft's Theory and Practice of Histological Techniques

Staining

Q17 Staining · Easy

In H&E staining, hematoxylin stains:

  1. A: Nuclei blue-purple
  2. B: Collagen green
  3. C: Fat red
  4. D: Cytoplasm pink
Show answer

Answer: A — Nuclei blue-purple

Eosin stains cytoplasm and collagen pink.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q18 Staining · Medium

In regressive hematoxylin staining, excess stain is removed by:

  1. A: Blueing in tap water
  2. B: Differentiation in acid alcohol
  3. C: Eosin
  4. D: Xylene
Show answer

Answer: B — Differentiation in acid alcohol

Blueing (alkaline solution) then turns the hematoxylin blue.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q19 Staining · Easy

Glycogen, mucins and basement membranes stain magenta with:

  1. A: Sudan black
  2. B: Congo red
  3. C: Periodic acid-Schiff (PAS)
  4. D: Perls Prussian blue
Show answer

Answer: C — Periodic acid-Schiff (PAS)

Diastase digestion removes glycogen, confirming it.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q20 Staining · Medium

Amyloid shows apple-green birefringence under polarized light with:

  1. A: Masson trichrome
  2. B: Oil red O
  3. C: PAS
  4. D: Congo red
Show answer

Answer: D — Congo red

Section thickness (8-10 micrometers) improves detection.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q21 Staining · Easy

Hemosiderin (ferric iron) is shown in blue with:

  1. A: Perls Prussian blue
  2. B: Von Kossa
  3. C: Ziehl-Neelsen
  4. D: Gram stain
Show answer

Answer: A — Perls Prussian blue

Von Kossa demonstrates calcium (phosphate) as black deposits.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q22 Staining · Medium

Fat is demonstrated with Oil red O on:

  1. A: Paraffin sections
  2. B: Frozen sections
  3. C: Decalcified sections
  4. D: Resin sections
Show answer

Answer: B — Frozen sections

Lipids are dissolved by alcohol and xylene during paraffin processing.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q23 Staining · Medium

Masson trichrome stains collagen:

  1. A: Yellow
  2. B: Red
  3. C: Blue or green
  4. D: Black
Show answer

Answer: C — Blue or green

Muscle and cytoplasm stain red; nuclei black. Used to assess liver fibrosis.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q24 Staining · Hard

The methyl green-pyronin stain colors RNA:

  1. A: Blue
  2. B: Black
  3. C: Green
  4. D: Red (pyronin)
Show answer

Answer: D — Red (pyronin)

DNA stains green-blue with methyl green; RNA-rich cytoplasm (e.g., plasma cells) stains red.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q25 Staining · Medium

Fungi in tissue are best shown with:

  1. A: Grocott methenamine silver (GMS) or PAS
  2. B: Perls stain
  3. C: Congo red
  4. D: Oil red O
Show answer

Answer: A — Grocott methenamine silver (GMS) or PAS

GMS stains fungal walls black and also stains Pneumocystis.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q26 Staining · Medium

Reticulin fibers are demonstrated with:

  1. A: Gram stain
  2. B: Silver impregnation (e.g., Gordon and Sweet)
  3. C: Sudan III
  4. D: Alcian blue
Show answer

Answer: B — Silver impregnation (e.g., Gordon and Sweet)

Reticulin is useful in liver and bone marrow biopsies.

Reference: Bancroft's Theory and Practice of Histological Techniques

Immunohistochemistry

Q27 Immunohistochemistry · Medium

Heat-induced epitope retrieval in IHC is needed mainly because:

  1. A: Hematoxylin destroys antigens
  2. B: Paraffin hides antigens
  3. C: Formalin cross-links mask epitopes
  4. D: Eosin blocks antibodies
Show answer

Answer: C — Formalin cross-links mask epitopes

Citrate (pH 6) or EDTA (pH 9) buffers are commonly used.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q28 Immunohistochemistry · Easy

Every IHC run should include:

  1. A: Only a negative control
  2. B: No controls if the reagent is new
  3. C: Only the patient slide
  4. D: Positive and negative controls
Show answer

Answer: D — Positive and negative controls

Controls confirm the staining worked and is specific.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q29 Immunohistochemistry · Medium

Which marker is typical of neuroendocrine tumors (e.g., pancreatic endocrine tumors)?

  1. A: Chromogranin A and synaptophysin
  2. B: Desmin
  3. C: CD45
  4. D: Alpha-hCG
Show answer

Answer: A — Chromogranin A and synaptophysin

Ki-67 is used to grade neuroendocrine tumors.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q30 Immunohistochemistry · Medium

Which pair supports a thyroid origin of a metastatic tumor?

  1. A: CD10 and CD20
  2. B: Thyroglobulin and TTF-1
  3. C: CK20 and CDX2
  4. D: PSA and PSAP
Show answer

Answer: B — Thyroglobulin and TTF-1

TTF-1 is also positive in lung adenocarcinoma; thyroglobulin is specific to thyroid.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q31 Immunohistochemistry · Medium

A tumor positive for CD45 (leukocyte common antigen) is most likely:

  1. A: Sarcoma
  2. B: Carcinoma
  3. C: Lymphoma
  4. D: Melanoma
Show answer

Answer: C — Lymphoma

Melanoma markers include S-100, SOX10, HMB-45 and Melan-A; carcinomas express cytokeratins.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q32 Immunohistochemistry · Medium

In breast cancer, HER2 status is assessed by:

  1. A: PAS
  2. B: Gram stain
  3. C: Congo red
  4. D: IHC with reflex ISH (FISH) for equivocal (2+) results
Show answer

Answer: D — IHC with reflex ISH (FISH) for equivocal (2+) results

Estrogen and progesterone receptors are also assessed by IHC.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q33 Immunohistochemistry · Medium

Can DNA be extracted from formalin-fixed paraffin-embedded (FFPE) tissue?

  1. A: Yes, though it is fragmented; it is routinely used for PCR and sequencing
  2. B: Only from frozen sections
  3. C: Only after decalcification with acid
  4. D: No, never
Show answer

Answer: A — Yes, though it is fragmented; it is routinely used for PCR and sequencing

Long formalin fixation and acid decalcification reduce DNA quality.

Reference: Bancroft's Theory and Practice of Histological Techniques

Cytology

Q34 Cytology · Easy

The Papanicolaou stain uses which counterstains for cytoplasm?

  1. A: Eosin only
  2. B: Orange G and EA (eosin azure) polychrome
  3. C: Safranin
  4. D: Methylene blue
Show answer

Answer: B — Orange G and EA (eosin azure) polychrome

Mature squamous cells are pink (eosinophilic) or blue-green (cyanophilic).

Reference: Koss' Diagnostic Cytology

Q35 Cytology · Medium

The Bethesda System is used to report:

  1. A: Bone marrow
  2. B: Thyroid FNA only
  3. C: Cervical cytology (and has separate systems for thyroid and other sites)
  4. D: Blood films
Show answer

Answer: C — Cervical cytology (and has separate systems for thyroid and other sites)

Categories include NILM, ASC-US, LSIL, HSIL and squamous cell carcinoma.

Reference: Koss' Diagnostic Cytology

Q36 Cytology · Medium

Koilocytes (cells with perinuclear halo and nuclear atypia) are associated with:

  1. A: Trichomonas
  2. B: Herpes simplex
  3. C: Candida
  4. D: Human papillomavirus (HPV)
Show answer

Answer: D — Human papillomavirus (HPV)

HPV testing is increasingly used for primary cervical screening.

Reference: Koss' Diagnostic Cytology

Q37 Cytology · Medium

Multinucleated cells with nuclear molding, margination and ground-glass chromatin in a Pap smear suggest:

  1. A: Herpes simplex virus
  2. B: Candida
  3. C: Bacterial vaginosis
  4. D: HPV
Show answer

Answer: A — Herpes simplex virus

The '3 Ms': multinucleation, molding, margination.

Reference: Koss' Diagnostic Cytology

Q38 Cytology · Easy

'Clue cells' (squamous cells covered with coccobacilli) suggest:

  1. A: Trichomonas
  2. B: Bacterial vaginosis (Gardnerella)
  3. C: Candida
  4. D: Herpes
Show answer

Answer: B — Bacterial vaginosis (Gardnerella)

BV is associated with a fishy odor on adding KOH (whiff test).

Reference: Koss' Diagnostic Cytology

Q39 Cytology · Medium

An advantage of liquid-based cytology over conventional smears is:

  1. A: It needs no stain
  2. B: No fixation needed
  3. C: Fewer obscuring factors (blood, mucus) and the same sample can be used for HPV testing
  4. D: Cheaper in every setting
Show answer

Answer: C — Fewer obscuring factors (blood, mucus) and the same sample can be used for HPV testing

Examples are ThinPrep and SurePath.

Reference: Koss' Diagnostic Cytology

Q40 Cytology · Medium

Air-dried fine-needle aspiration smears are best stained with:

  1. A: H&E
  2. B: Perls stain
  3. C: Papanicolaou
  4. D: Romanowsky stains such as Diff-Quik or May-Grunwald Giemsa
Show answer

Answer: D — Romanowsky stains such as Diff-Quik or May-Grunwald Giemsa

Rapid on-site evaluation (ROSE) often uses Diff-Quik.

Reference: Koss' Diagnostic Cytology

Q41 Cytology · Medium

Cell blocks from body fluids are useful because they:

  1. A: Allow paraffin sections for immunohistochemistry
  2. B: Replace cytospin
  3. C: Count cells
  4. D: Remove the need for fixation
Show answer

Answer: A — Allow paraffin sections for immunohistochemistry

IHC helps separate reactive mesothelial cells from metastatic carcinoma.

Reference: Koss' Diagnostic Cytology

Q42 Cytology · Medium

An adequate sputum specimen for cytology should contain:

  1. A: Only squamous cells
  2. B: Alveolar macrophages (showing a deep lower-respiratory sample)
  3. C: Only red cells
  4. D: Bacteria
Show answer

Answer: B — Alveolar macrophages (showing a deep lower-respiratory sample)

Early morning deep-cough specimens on 3 consecutive days improve yield.

Reference: Koss' Diagnostic Cytology

Lab practice & safety

Q43 Lab practice & safety · Easy

The most important step on receiving a histology specimen is:

  1. A: Discarding the request form
  2. B: Cutting it immediately
  3. C: Checking that patient identifiers on the container and request form match
  4. D: Photographing it
Show answer

Answer: C — Checking that patient identifiers on the container and request form match

Mislabeled specimens should not be processed until the discrepancy is resolved.

Reference: CAP: Retention of laboratory records and materials

Q44 Lab practice & safety · Medium

According to CAP guidance, wet (stock) tissue should be retained for at least:

  1. A: 24 hours
  2. B: 2 weeks after the final report
  3. C: 1 year
  4. D: 10 years
Show answer

Answer: B — 2 weeks after the final report

Paraffin blocks and slides are kept for 10 years under CAP; local regulations may differ.

Reference: CAP: Retention of laboratory records and materials

Q45 Lab practice & safety · Medium

Formaldehyde is a health hazard mainly because it is a:

  1. A: Respiratory irritant, sensitizer and known human carcinogen
  2. B: Explosive
  3. C: Harmless vapor
  4. D: Radioactive substance
Show answer

Answer: A — Respiratory irritant, sensitizer and known human carcinogen

Use fume hoods, ventilation and exposure monitoring.

Reference: Bancroft's Theory and Practice of Histological Techniques

Q46 Lab practice & safety · Medium

Xylene exposure is reduced by:

  1. A: Working on an open bench
  2. B: Using fume extraction or substituting safer clearing agents
  3. C: Heating it
  4. D: Mixing it with water
Show answer

Answer: B — Using fume extraction or substituting safer clearing agents

Xylene is flammable and neurotoxic.

Reference: Bancroft's Theory and Practice of Histological Techniques