Certified Histotechnician (HT) Practice Exam 2025-
2026[Complete Exam prep Questions with verified
Answers]
1. What is the primary purpose of formalin in tissue processing?
A. Staining tissue sections
B. Dehydrating tissue
C. Fixing tissue
D. Clearing tissue
Formalin preserves tissue morphology by cross-linking proteins, preventing
autolysis and decomposition.
2. Which type of microtome is typically used for paraffin-embedded tissue?
A. Cryostat
B. Vibratome
C. Rotary microtome
D. Ultramicrotome
A rotary microtome is standard for cutting thin, paraffin-embedded tissue
sections for histology.
3. What is the purpose of dehydration in tissue processing?
A. Remove fixative
B. Replace water with alcohol
C. Make tissue transparent
D. Harden tissue
Dehydration gradually removes water from tissue, allowing infiltration with
paraffin.
4. Which reagent is commonly used as a clearing agent before paraffin
embedding?
A. Ethanol
B. Xylene
C. Toluene
D. Formalin
Clearing agents like toluene or xylene remove alcohol and make tissue
receptive to paraffin.
,5. What thickness is typical for paraffin sections used in routine histology?
A. 0.5–1 µm
B. 2–3 µm
C. 4–6 µm
D. 10–12 µm
Paraffin sections are usually 4–6 µm thick for optimal staining and morphology.
6. Which staining method is used to demonstrate carbohydrates like
glycogen?
A. Hematoxylin and eosin
B. Periodic acid–Schiff (PAS)
C. Masson’s trichrome
D. Oil Red O
PAS stains polysaccharides and mucosubstances magenta, highlighting
glycogen.
7. Bouin’s solution is commonly used to fix which tissue type?
A. Brain
B. Testes
C. Liver
D. Bone
Bouin’s fixative preserves soft, delicate tissues like testes and improves staining
of collagen.
8. What is the main component of paraffin used in embedding?
A. Silicone
B. Waxes
C. Paraffin wax
D. Resin
Paraffin wax provides support to tissue for thin sectioning.
9. Which of the following is a cryostat used for?
A. Cutting frozen sections
B. Embedding tissue
C. Fixation
D. Dehydration
Cryostats allow rapid sectioning of frozen tissue, often for intraoperative
diagnosis.
, 10. What is the purpose of xylene in histology?
A. Fix tissue
B. Clear tissue of alcohol
C. Stain nuclei
D. Dehydrate tissue
Xylene is a clearing agent that replaces alcohol and prepares tissue for paraffin
infiltration.
11. Which fixative is considered non-coagulant and penetrates tissue slowly?
A. Alcohol
B. Formalin
C. Acetone
D. Mercuric chloride
Formalin is a non-coagulant fixative that cross-links proteins without
precipitating them.
12. What is the principle of hematoxylin staining?
A. Stains cytoplasm pink
B. Stains carbohydrates
C. Stains nuclei blue-purple
D. Stains lipids red
Hematoxylin binds to acidic nuclear components, staining nuclei blue-purple.
13. Which of the following is used to remove paraffin from tissue sections
before staining?
A. Alcohol
B. Formalin
C. Xylene
D. Water
Xylene dissolves paraffin, allowing sections to be rehydrated for staining.
14. What is the correct sequence in routine paraffin processing?
A. Fixation → Clearing → Dehydration → Embedding
B. Fixation → Dehydration → Clearing → Embedding
C. Clearing → Fixation → Dehydration → Embedding
D. Dehydration → Fixation → Clearing → Embedding
Tissues are fixed, dehydrated, cleared, and then infiltrated with paraffin.
15. Which stain is used to demonstrate connective tissue fibers?
A. Hematoxylin and eosin
2026[Complete Exam prep Questions with verified
Answers]
1. What is the primary purpose of formalin in tissue processing?
A. Staining tissue sections
B. Dehydrating tissue
C. Fixing tissue
D. Clearing tissue
Formalin preserves tissue morphology by cross-linking proteins, preventing
autolysis and decomposition.
2. Which type of microtome is typically used for paraffin-embedded tissue?
A. Cryostat
B. Vibratome
C. Rotary microtome
D. Ultramicrotome
A rotary microtome is standard for cutting thin, paraffin-embedded tissue
sections for histology.
3. What is the purpose of dehydration in tissue processing?
A. Remove fixative
B. Replace water with alcohol
C. Make tissue transparent
D. Harden tissue
Dehydration gradually removes water from tissue, allowing infiltration with
paraffin.
4. Which reagent is commonly used as a clearing agent before paraffin
embedding?
A. Ethanol
B. Xylene
C. Toluene
D. Formalin
Clearing agents like toluene or xylene remove alcohol and make tissue
receptive to paraffin.
,5. What thickness is typical for paraffin sections used in routine histology?
A. 0.5–1 µm
B. 2–3 µm
C. 4–6 µm
D. 10–12 µm
Paraffin sections are usually 4–6 µm thick for optimal staining and morphology.
6. Which staining method is used to demonstrate carbohydrates like
glycogen?
A. Hematoxylin and eosin
B. Periodic acid–Schiff (PAS)
C. Masson’s trichrome
D. Oil Red O
PAS stains polysaccharides and mucosubstances magenta, highlighting
glycogen.
7. Bouin’s solution is commonly used to fix which tissue type?
A. Brain
B. Testes
C. Liver
D. Bone
Bouin’s fixative preserves soft, delicate tissues like testes and improves staining
of collagen.
8. What is the main component of paraffin used in embedding?
A. Silicone
B. Waxes
C. Paraffin wax
D. Resin
Paraffin wax provides support to tissue for thin sectioning.
9. Which of the following is a cryostat used for?
A. Cutting frozen sections
B. Embedding tissue
C. Fixation
D. Dehydration
Cryostats allow rapid sectioning of frozen tissue, often for intraoperative
diagnosis.
, 10. What is the purpose of xylene in histology?
A. Fix tissue
B. Clear tissue of alcohol
C. Stain nuclei
D. Dehydrate tissue
Xylene is a clearing agent that replaces alcohol and prepares tissue for paraffin
infiltration.
11. Which fixative is considered non-coagulant and penetrates tissue slowly?
A. Alcohol
B. Formalin
C. Acetone
D. Mercuric chloride
Formalin is a non-coagulant fixative that cross-links proteins without
precipitating them.
12. What is the principle of hematoxylin staining?
A. Stains cytoplasm pink
B. Stains carbohydrates
C. Stains nuclei blue-purple
D. Stains lipids red
Hematoxylin binds to acidic nuclear components, staining nuclei blue-purple.
13. Which of the following is used to remove paraffin from tissue sections
before staining?
A. Alcohol
B. Formalin
C. Xylene
D. Water
Xylene dissolves paraffin, allowing sections to be rehydrated for staining.
14. What is the correct sequence in routine paraffin processing?
A. Fixation → Clearing → Dehydration → Embedding
B. Fixation → Dehydration → Clearing → Embedding
C. Clearing → Fixation → Dehydration → Embedding
D. Dehydration → Fixation → Clearing → Embedding
Tissues are fixed, dehydrated, cleared, and then infiltrated with paraffin.
15. Which stain is used to demonstrate connective tissue fibers?
A. Hematoxylin and eosin
