Histo Flashcards
All processes are done in an automafic tissue processor, EXCEPT:
A. Fixation
B. Dehydration
C. Impregnation
automatic ristue
D. Embedding
D. Embedding
The AUTOTECHNI COM is an automatic tissue processor. The last container through which the surgical tissue sections pass through contains:
A. Formalin
B. Alcohol
C. Paraffin
D. Acetone
C. Paraffin
All of the following are good characteristics of a fixing fluid, EXCEPT:
A. It must be cheap, stable and safe to handle.
B. It must inhibit bacterial decomposition and autolysis
C. It must be isotonic, causing minimal physical and chemical alteration of the cells.
LEMAR REVIEWIHUE]
D. It must make cellular components sensitive to subsequent processing.
D. It must make cellular components sensitive to subsequent processing.
The amount of the fixing fluid should be approximately:
A. 5-10 times the volume of the specimen
B. 10-20 times the volume of the specimen
C. 20-30 times the volume of the specimen
D. 40-50 times the volume of the specimen
B. 10-20 times the volume of the specimen
All of the following are micronanatomical fixatives, EXCEPT:
A. 10% Formalin
B. Bouin’s solution
C. Zenker’s solution
D. Flemming’s fluid
D. Flemming’s fluid
Nuclear fixatives are those which preserves the nuclear structures (e.g., chromosomes). They usually contain _____ as their primary component due to its affinity for nuclear chromatin. They have a pH of 4.6 or less.
A. Osmium tetroxide
B. Nitric acid
C. Trichloroacetic acid
D. Glacial acetic acid
D. Glacial acetic acid
Cytoplasmic fixatives are those that preserves cytoplasmic structures in particular. They must never contain glacial acetic acid which destroys mitochondria and Golgi bodies of the cytoplasm. They have a pH of more than 4.6. All of the following are cytoplasmic fixatives, except:
A. Helly’s fluid
В. Zenker’s fluid
C. Regaud’s fluid
D. Orth’s fluid
В. Zenker’s fluid
All of the following are metallic fixatives, EXCEPT:
A. Zenker’s fluid
B. Helly’s solution
C. Regaud’s fluid
D. Carnoy’s fluid
D. Carnoy’s fluid
All of the following are mercurial fixatives, EXCEPT:
A. B-5 fixative
8. Zenker’s fluid
C. Orth’s fluid
D. Hedenhain’s Susa
C. Orth’s fluid
These fixatives are recommended for glycogen fixation:
A. Aldehyde fixatives
B. Mercurial fixatives
C. Alcoholic fixatives
D. Chromate fixatives
C. Alcoholic fixatives
Most widely used fixative for electron microscopy:
A. Mercurial fixative
B. Picric acid fixitives
C. Glacial acetic acid
D. Osmium tetroxide fixatives
D. Osmium tetroxide fixatives
Fixative for the preservation of fats:
A. Helly’s fluid
B. Zenker’s fluid
C. Formalin
D. Newcomer’s fluid
C. Formalin
Best fixative for the nervous system.
A. Formalin
B. B-5 fixative
C. Helly’s fluid
D. Regaud’s fluid
A. Formalin
It is added as a preservative to formaldehyde. This will prevent its decomposition to formic acid or precipitation to paraformaldehyde.
A. Butanol
B. Elhanol
C. Methanol
D. Acetone
C. Methanol
Formaldehyde is sually buffered at pH 7 with _ buffer.
A. Citrate
B. Bicarbonate
C. Carbonic acid
D. Phosphate
D. Phosphate
Formaldehyde fumes are irritating to the nose and eyes and may cause:
A. Allergic rhinitis
B. Sinusitis
C. Excessive lacrimation
D. All of these
D. All of these
In tissues containing much blood (e.g., spleen), unbuffered formalin leads to the formation of dark brown artifact pigment granules. These pigments may be removed with:
А. lodine
B. Sodium thiosulfate
C. Picric acid
D. Glacial acetic acid
C. Picric acid
Concentrated solutions of this fixing agent must NEVER be neutralized since this might precipitate violent explosions.
A. Formaldehyde
B. Mercuric chloride
C. Potassium dichromate
D. Alcoholic fixatives
A. Formaldehyde
It is considered as the most common metallic fixative:
A. Lead
В. Mercuric chlonde
C. Osmium tetroxide
D. Chromate
В. Mercuric chlonde
Fixatives that give the best results with metachromatic staining and are the routine fixatives of choice for preservation of detail for photography:
A. Formalin fixatives
B. Mercurial fixatives
C. Lead fixatives
D. Chromate fixatives
B. Mercurial fixatives
Helly’s solution has the same components as Zenker’s, but instead of glacial acetic acid, Helly’s contains:
A. Mercuric chloride
B. Potassium dichromate
C. Sodium sulfate
D. Formaldehyde
D. Formaldehyde
This fixative is recommended for tumor biopsies especially the skin.
A. Zenkers fluid
B. Helly’s fluid
C. Heidenhain’s Susa
D. Flemming’s fluid
C. Heidenhain’s Susa
Tissues fixed with mixtures containing mercuric chloride may contain black precipitates of mercury, EXCEPT:
A. B-5 fixative
B. Zenker’s fluid
C. Helly’s fluid
D. Heidenhain’s Susa solution
D. Heidenhain’s Susa solution
Black deposits of mercuric chloride may be removed with:
A. lodine
В. Picric acid
C. Ammonia water
D. Osmium tetroxide
A. lodine
It is recommended mainly for tumor biopsies especially of the skin; it is an excellent cytologic fixative.
A. B-5 fixative
B. Zenker’s fluid
C. Helly’s fluid
D. Heidenhain’s Susa solution
D. Heidenhain’s Susa solution
It is recommended for demonstration of chromatin, mitochondria, mitotic figures, Golgi bodies, RBC and colloid-containing tissues.
A. Carnoy’s fluid
B. Newcomer’s fluid
C. Regaud’s fluid
D. Zenker’s fluid
C. Regaud’s fluid
This fixative recommended for the study of early degenerative processes and tissue necrosis. It demonstrate Rickertsiae and other bacteria.
A. Acetone
B. Orth’s fluid
C. Ethyl alcohol
D. Bouin’s solution
B. Orth’s fluid
It is recommended for acid mucopolysaccharides.
A. Aldehye fixatives
B. Picric acid fixatives
C. Lead fixatives
D. Bouin’s solution
C. Lead fixatives
This fixative is highly explosive when dry, and therefore must be kept moist with distilled water or saturated alcohol during storage.
A. Osmic acid
B. Mercuric chloride
C. Picric acid
D. Acetone
C. Picric acid
It is recommended for fixation of embryos and pituitary biopsies:
A Zenker’s fluid
B. Bouin’s solution
C. Orth’s fluid
D. Regaud’s fluid
B. Bouin’s solution
Bouin’s is appropriate for fixing the following structures, EXCEPT:
A. Fragmentary biopsies
B. Endometrial curettings
C. Glycogen
D. Kidney structures
D. Kidney structures
All of the following fixatives contain picric acid, EXCEPT:
A. Bouin’s fluid
B. Brasil’s fixalive
C. Gendre’s fixative
D. Carnoy’s fluid
D. Carnoy’s fluid
- Acetic acid is normally used in conjunction with other fixatives to a compound solution. It solidifies at ____, hence the name glacial acetic acid.
А. 7 C
B. 7 F
С. 17°C
D. 17°F
С. 17°C
All of the following statements are true for glacial acetic acid, EXCEPT:
A. It fixes and precipitates nucleoproteins
B. Precipitates chromosomes and chromatin materials, hence is useful in the study of the nuclear components of the cell
C. It causes tissues (especially those containing collage) to shrink
D. It is contraindicated for cytoplasmic fixation, since it destroys mitochondria and Golgi elements of the cell
C. It causes tissues (especially those containing collage) to shrink
Alcohol rapidly denatures and precipitates proteins by destroying hydrogen and other bonds. As a fixative, it must be used in concentrations ranging from _”
A. 30 to 50%
B. 50 to 70%
C. 60 to 70%
D. 70 to 100%
D. 70 to 100%
It is excellent for fixing dry and wet smears, blood smears and bone marrow tissues.
A Carnoy’s tod
B. Hellys solution
C. Acetone
D. Methyl alcohol
D. Methyl alcohol
This fixative is considered to be as the most rapid fixative. It fixes and dehydrates at the same time.
A. Flemming’s fluid
B. Helly’s fluid
C. Bouin’s fluid
D. Carnoy’s fluid
D. Carnoy’s fluid
It is recommended fur fixing chromosumes, lymph glands and urgent biopsies.
A. Flemming’s fluid
B. Helly’s fluid
C. Bouin’s fluid
D. Carnoy’s fluid
D. Carnoy’s fluid
- It is used in fixing brain tissues for diagnosis of rabies.
A. Formaline
B. Picric acid
C. Osmium tetroxide
D. Acetone
D. Acetone
Factors that slow down (retard) fixation, EXCEPT:
A. Presence of mucus and blood
B. Presence of fats
C. Cold temperature
D. Agitation
D. Agitation
The most useful primary fixative(s) for electron microscopy is(are):
A. Osmium tetroxide
B. Glutaraldehyde
C. Paraformaldehyde
D. All of these
D. All of these
All are advantages of microwave fixation, EXCEPT:
A. Tissues are heated right through the block in short time
B. Reduces time taken for immunohistochemistry
C. Penetrates even thick tissues
D. Useful in preserving neurochemical substances in brain
C. Penetrates even thick tissues
Organ that should not be dissected before they are fixed:
A. Uterus
B. Liver
C. Eyes
D. Lungs
C. Eyes
This organ is usually suspended whole in 10% buffered formalin for 2 to 3 weeks to ensure fixation and some hardening prior to sectioning.
A. Lungs
B. Liver
C. Brain
D. Amputated foot
C. Brain
For fixation, tissues should not be more than 5 mm. thick except in ___ (in which case tissue slices may be 1-2 cm thick), with minimum squeezing and handling.
A. Liver
B. Uterus
C. Intestines
D. Lung edema
D. Lung edema
The process of decalcification is best performed:
A. Before fixation
B. After fixation
C. After impregnation
D. After staining
B. After fixation
The recommended ratio of fluid to tissue volume for decalcification is:
A. 5 to 1
B. 10 to 1
C. 15 to 1
D. 20 to 1
D. 20 to 1
The ideal time required for decalcifying tissues is:
A. 2 to 4 hours
B. 4 to 6 hours
C. 12 to 14 hours
D. 24 to 48 hours
D. 24 to 48 hours