meowsto blooket final

What stain can be done to represent simple neutral lipids?
A. Congo red
B. Oil Red O
C. Hematoxylin
D. Masson's trichrome

b

When staining for amyloid, the birefringent colour is green under the polarizing light. Is this correct?

yes

How would amyloid deposits stain in the H&E stain?
A. Bright red
B. Pale pink
C. Eosinophilic and amorphous
D. Blue-black

c

What is the mechanism of staining for the Congo red stain?
A. Physical absorption
B. Ionic bonding to protein
C. Hydrogen bonding to β-pleated sheets
D. Enzyme reaction

c

When we are staining with Oil Red O (ORO), which lipids are we demonstrating?
A. Phospholipids
B. Neutral fats and triglycerides
C. Cholesterol esters only
D. Glycolipids

b

T/F? Simple neutral fats will be lost during routine processing and embedding.

t

How can you treat simple neutral lipids to become insoluble?
A. By freezing the tissue
B. By heating the section
C. By treating with potassium dichromate
D. By fixing with Bouin’s solution

c

What is the mechanism of staining for Oil Red O (ORO)?
A. Ionic bonding
B. Covalent binding
C. selective solubility
D. Precipitation

c

How would you end up with a false negative result for lipid staining?
A. Using unfixed frozen sections
B. Using paraffin-embedded tissue
C. Staining at room temperature
D. Overstaining

b

Is the Oil Red O stain a physical method of demonstrating fat?

yes

Why must you ring the coverslip after the ORO staining?
A. To prevent drying
B. To prevent evaporation
C. To enhance visualization
D. To fix the lipid

b

What could happen if you cut an amyloid section at 15 microns?
A. The section will stain too lightly
B. yellow birefringence under polarized light
C. Congo red will not bind
D. The tissue will shrink

b

If you see white birefringence, what is that indicative of?
A. Glycogen
B. Lipofuscin
C. Uric acid crystals
D. salt crystals

d

Which of the following is not a differential stain?
A. Gram stain
B. Ziehl-Neelsen
C. Giemsa
D. GMS

D

If you get variable staining after performing the Gram stain properly, what is this an indication of?
A. Incomplete fixation
B. Antibiotic treatment or aging of bacteria
C. Over-decolorization
D. Too thick a smear

B

If you are staining an organism that is resistant to acid, how would it appear once you complete an acid-fast stain?
A. Blue
B. Clear
C. Red/pink
D. Green
Answer: C

C

Why is mycobacteria difficult to stain with the Gram stain?
A. Lack of cell wall
B. Presence of a capsule
C. Waxy lipid layer in the cell wall
D. Too small to stain

C

Which staining method contains more phenol?
A. Ziehl-Neelsen
B. Kinyoun
C. Gram
D. GMS

B

What is the reducing agent in the Warthin-Starry stain?
A. Hydroquinone
B. Formalin
C. Uranyl nitrate
D. Silver nitrate

A

What purpose does the chromic acid have in the GMS stain?
A. Fixation
B. Bleaching
C. Oxidation of fungal walls
D. Reduction of silver

C

GMS utilizes what kind of silver?
A. Colloidal silver
B. Ammoniacal silver
C. Silver nitrate
D. Metallic silver

B

What is the correct order for the GMS stain?
A. Oxidation → Silver → Toning → Thiosulfate → Counterstain
B. Fixation → Counterstain → Oxidation → Reduction
C. Silver → Oxidation → Toning → Thiosulfate
D. Toning → Silver → Oxidation → Counterstain

A

Which step is the most critical step in the GMS stain?
A. Toning
B. Thiosulfate
C. Silver impregnation
D. Oxidation

D

. A stain that may be used to demonstrate calcium is ___?
A. Fontana-Masson
B. Alizarin Red
C. Gram
D. Ziehl-Neelsen

B

What is the expected result of hemosiderin in Schmorl's?
A. Blue-black
B. Red
C. Green
D. Brown

A

Which of the following is an exogenous pigment?
A. Hemosiderin
B. Melanin
C. Lipofuscin
D. Carbon (anthracotic pigment)

D

An aid to the definite identification of anthracotic pigment is its:
A. Red fluorescence
B. Solubility in alcohol
C. Resistance to bleach and birefringence
D. Metallic sheen

C

The Turnbull stain is used for the detection of:
A. Calcium
B. Iron in the ferrous (Fe²⁺) state
C. Ferric iron (Fe³⁺)
D. Lipids

B

A good control for the Prussian Blue (PPB) stain would be:
A. Liver with hemosiderin
B. Spleen with amyloid
C. Brain with calcium
D. Skin with melanin

a

In the Hall technique, bilirubin is oxidized to biliverdin by:
A. Potassium dichromate
B. Fouchet’s reagent
C. Chromic acid
D. Nitric acid

b (trichloroacetic acid (TCA) + ferric chloride)

The Fontana-Masson technique will demonstrate substances that can:
A. Reduce silver without an external reducer
B. Bind hematoxylin
C. Absorb oil-soluble dyes
D. Oxidize rapidly in air

a

Pigment lying on top of tissue is most likely:
A. Melanin
B. Hematoidin
C. Artifact pigment
D. Lipofuscin

c

Polarized light can be used to assist in the identification of which of the following pigments?
A. Carbon
B. Uric acid
C. Hemosiderin
D. Lipofuscin

b

In some IHC techniques, alkaline phosphatase functions as the:
A. Primary antibody
B. Chromogen
C. Enzyme label
D. Substrate

c

If 3-amino-9-ethylcarbazole is used as the chromogen, the hematoxylin used for counterstaining should be:
A. Acidic
B. Basic
C. Alcoholic
D. Aqueous

d

T/F? Negative tissue antigen control may be run by substituting for the primary antibody the diluent in which the antibody is prepared.

t

T/F? Zinc formalin doesn’t preserve immunoreactivity, so Bouin’s is used.

f

Paraffin sections stained with the immunoperoxidase technique show excess background staining. Which of the following could be the explanation for this?
A. Not enough chromogen
B. Endogenous peroxidase not blocked
C. Incorrect fixative
D. Section too thin

b

Both the positive control and specimen stained show weak staining. What is most likely the reason?
A. Overstaining
B. Wrong counterstain
C. Incorrect antibody dilution or expired antibody
D. Incorrect mounting media

c

T/F? EIER is another form of blocking.

f

In the bloody areas of a tissue section stained, there’s a marked reaction of the red blood cells. What could this be a result of?
A. Overdecolorization
B. Endogenous enzyme activity
C. Non-specific antibody binding
D. Incomplete blocking of endogenous peroxidase

d