All Correct Answers 2026 Updated.
An example of an additive is one that contains:
A. Picric acid
B. Acetic acid
C. Ethyl alcohol
D. Acetone - Answer Picric Acid
When compared with tissue fixed in formalin, tissue fixed in zinc-formalin will show:
A. Better ultrastructural preservation
B. Decreased immunoreactivity
C. Increased enzyme activity
D. Superior nuclear detail - Answer Superior nuclear detail
Microscopic examination of an H&E stained section fixed in formalin shows marked nuclear
bubbling. One most often sees this artifact if the specimen is processed following:
A. Incomplete fixation
B. Prolonged fixation
C. Microwave fixation
D. Frozen sectioning - Answer Incomplete fixation
Microscopic evaluation of H&E stained sections from a surgically removed small bowel
specimen shows an absence of much of the epithelium in otherwise normal tissue. This most
likely resulted from:
A. Mechanical trauma
B. Delayed fixation
C. Ulceration
D. Poor choice of fixative - Answer Delayed fixation
A specimen of kidney must be shipped to another city for immunofluorescence studies. The
specimen should be placed in:
A. Saline
B. Michel solution
C. Buffered formalin
,D. Orth solution - Answer Michel solution
A certain project requires a fixative that contains acetic acid yet stabilizes erythrocyte
membranes. One fixative that could be used is:
A. Zenker solution
B. Bouin solution
C. Gendre solution
D. Hollande solution - Answer Hollande solution
When the microwave oven is used for fixation, the most critical factor is the:
A. Preparation of the formalin solution
B. Use of glass containers
C. Control of the temperature
D. Osmolality of the fixative solution - Answer Control of the temperature
To adequately remove the calcium in a specimen containing areas of microcalcification, the
tissue could be fixed in:
A. Hollande solution
B. NBF
C. B-5 solution
D. Zamboni solution - Answer Hollande solution
What fixative contains copper acetate?
A. Hollande
B. Bouin
C. Gendre
D. Zamboni - Answer Hollande
A specimen is submitted with the statement that it was fixed in formalin. Microscopic sections
show marked lysis of erythrocytes. This indicates that the fixative most likely was:
A. Prepared with too much formalin
B. Buffered above neutrality
C. Acidified with acetic acid
D. Not formalin - Answer Acidified with acetic acid
Fixatives are classified as additive because of the:
,A. Addition of several chemicals to the solution
B. Addition, or binding of the fixative to tissue proteins
C. Additional reactions occurring with longer fixation
D. Additional reactive tissue sites available for dye binding - Answer Addition, or binding of
the fixative to tissue proteins
Kidney biopsy tissue has been fixed in phosphate-buffered glutaraldehyde for 2 hours and then
placed in phosphate buffer solution. If a portion of this tissue is processed for light microscopy,
sections would most likely show:
A. Very poor glomerular preservation
B. Decreased uptake of hematoxylin
C. Lysis of cytoplasmic elements
D. Nonspecific PAS staining - Answer Nonspecific PAS staining
Uric acid crystals are preserved ONLY when tissue is fixed in:
A. Absolute alcohol
B. NBF
C. Orth solution
D. Zamboni solution - Answer Absolute alcohol
Improper preservation of tissue will result if there is:
A. A delay in fixation
B. A rapid penetration of the fixing fluid
C. Prolonged storage following formalin fixation
D. Rapid dehydration, clearing, embedding, and sectioning - Answer A delay in fixation
A good fixative will:
A. Render cell constituents soluble
B. Minimize differences in tissue refractive indices
C. Protect tissue against alteration during subsequent processing
D. Minimally affect tissue metabolic processes - Answer Protect tissue against alteration
during subsequent processing
The function of methanol in commercial formalin solutions is to:
A. Retard the polymerization of formaldehyde
B. Prevent the formation of formic acid
, C. Stabilize the formalin at a basic pH
D. Permit room temperature storage of formalin - Answer Retard the polymerization of
formaldehyde
In electron microscopy, Zamboni fluid, glutaraldehyde, and osmium tetroxide function as:
A. Dehydrating agents
B. Clearing agents
C. Embedding media
D. Fixative solutions - Answer Fixative solutions
Tissue will remain unfixed if placed in:
A. Potassium dichromate
B. Sodium borate
C. Osmium tetroxide
D. Zinc chloride - Answer Sodium borate
Bouin's solution is contraindicated for:
A. Small tissue biopsies
B. Tissue intended for subsequent trichrome stains
C. Tissue to be stained by the Feulgen reaction
D. Routine tissue sections - Answer Tissue to be stained by the Feulgen reaction
Formalin pigment can be removed from tissue sections by treatment with 10%:
A. Hydrochloric acid in 70% alcohol
B. Nitric acid in 70% alcohol
C. Sulfuric acid in 70% alcohol
D. Ammonium hydroxide in 70% alcohol - Answer Ammonium hydroxide in 70% alcohol
Stock neutralized formalin is prepared in the laboratory by storing the solution over a layer of
calcium carbonate. The solution withdrawn from this stock container will:
A. Become acidic
B. Become alkaline
C. Remain neutral
D. Exhibit metachromasia - Answer Become acidic