Specimen Preparation Flashcards
7 cards from real Histology Certification practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Specimen Preparation flashcards as text
Which of the following best describes the role of xylene in standard tissue processing?
Answer: Clearing agent miscible with paraffin
Xylene is a clearing agent that removes alcohol from tissue and is fully miscible with melted paraffin wax.
When processing a core needle biopsy, the cassette used should be:
Answer: A biopsy/mesh cassette to prevent tissue loss
Biopsy mesh cassettes trap small tissue fragments, preventing loss during agitation in automated processors.
The pH of 10% neutral buffered formalin (NBF) should be maintained at approximately:
Answer: 6.8–7.2
NBF is buffered to near-neutral pH (6.8–7.2) to minimize formalin pigment artifact and preserve antigenicity.
Decalcification with strong mineral acids (e.g., HCl) compared to EDTA-based decalcification:
Answer: Is faster but causes more tissue and nuclear damage
Strong acid decalcification is rapid but degrades tissue morphology and nucleic acids, making EDTA preferable when downstream molecular or IHC studies are planned.
Which artifact results from air drying a smear before fixation in cytological preparations?
Answer: Cellular swelling and poor nuclear staining
Air drying before fixation causes cells to swell and nuclei to stain poorly, degrading cytological detail.
Prolonged over-fixation in formalin primarily leads to:
Answer: Excessive cross-linking that masks antigens
Over-fixation creates excessive methylene bridge cross-links that mask epitopes, reducing IHC staining sensitivity.
What is the purpose of a 'flotation bath' in histological sectioning?
Answer: To float and flatten paraffin ribbons for mounting on slides
Warm water in the flotation bath causes paraffin ribbons to expand and flatten, eliminating folds before mounting on glass slides.