BOC 2021 HTL Pool Interactive Practice Exam Flashcards
Mycobacterium tuberculosis may be demonstrated with which of the following stains?
A. Crystal violet
B. Leucofuchsin
C. Acid fuchsin
D. Carbol-fuchsin
D. Carbol-fuchsin
Mycobacterium tuberculosis may be demonstrated with carbol-fuchsin. The stain is a modified Ziehl-Neelson formulation used for staining acid fast bacteria.
Which of the following fixatives is BEST when used at approximately neutrality?
A. Glyoxal
B. Formalin
C. Bouin
D. Zenker
B. Formalin
All of the fixatives except formalin are acidic; formalin should be approximately neutral to prevent the formation of formalin pigment. Glyoxal is preferably used at pH 4.0.
Which of the following histologic features is unique to cardiac muscle?
A. Cross-striations
B. Peripherally located nuclei
C. Intercalated discs
D. Nonbranching fibers
C. Intercalated discs
Intercalated discs are unique to cardiac muscle
Can you rember what the
NFPA diamond grid looks like and what each diamond signifies?
Blue= health haz
Red= fire haz
Yellow= instability haz
White= Specific hazard (usually blank for most reagents)
Which of the chemical reagents used for decalcification is the slowest acting?
A. Hydrochloric acid
B. Nitric acid
C. Formic acid
D. EDTA
D. EDTA
EDTA is a very slow acting as a dealcifier, making its use easily controlled
In the Gomori 1-step trichrome stain, collagen stains:
A. yellow
B. green
C. black
D. red
B. Green
Collagen stains green in the Gomori 1-step trichrome procedure.
Nuclei = black
Cytoplasm, keratin, muscle fibers=red
Collagen and mucus= green or blue
The purpose of diastase in a PAS stain is to:
A. remove glycogen from cells
B. enhance the intensity of the PAS stain
C. eliminate interfering lipoprotein
D. combine with disaccharide sugars
A. Remove glycogen from cells
Diastase is used to remove glycogen from cells in the PAS stain.
Chromic acid is used in the method shown below to:
A. prevent overoxidatoin of weak polysaccharides
B. mordant formaldehyde-fixed tissues
C. oxidize polysaccharides to aldehydes
D. begin impregnation
C. Oxidize polysaccharides to aldehydes
Chromic acid is used in the GMS procedure to oxidize polysaccharides to aldehydes.
A protozoan that causes outbreaks of severe and relentless diarrhea among patients with acquired immunodeficiency syndrome (AIDS) is:
A. Cryptosporidium muris
B. Leishmania donovani
C. Giardia lamblia
D. Toxoplasma gondii
A. Cryptosporidium muris
Cryptosporidium is one of a group of protozoa that causes severe and relentless outbreaks of diarrhea among AIDS patients.
Tissue must be dehydrated before placing it in:
A. Dioxane
B. Xylene
C. Tetrahydrofuran
D. Acetone
B. Xylene
Dioxane, tetrahydrofuran, & acetone are miscible with both the fixative and paraffin.
A brownish black birefringent pigment is interfering with some special stains and should be removed prior to staining with:
A. Lugol iodine
B. Running water
C. 70% alcohol containing ammonium hydroxide
D. Sodium thiosulfate
C. 70% alcohol containing ammonium hydroxide
birefringent =pigment is most likely the result of acidic formalin fixation. Formalin pigment can be removed by treating the tissue with 70% alcohol containing ammonium hydroxide.
What are spirochetes? What is the biggest clue in identifying them?
Spirochetes are spiral shapped bacteria that cause diseases like syphilis, lyme disease, and relapsing fever. See a wiggly/spiral black shape in a Warthin-Starry silver stain, that’s probably them.
What is the preferred fixative for Congo red staining?
Carnoy fixative
The time needed for infiltration of paraffin into a tissue specimen is dependent upon all of the following EXCEPT the:
A. fixative used
B. thickness of the specimen
C. tissue type
D. use of vacuum
A. Fixative used
The fixative used on a specimen will have no impact on the time needed for paraffin infiltration.
A dangerous materials warning system chart developed by the NFPA is in use in the laboratory. A reagent is identified with a red background and the number three (3). This indicates a compound that:
A. will cause irritation if not treated
B. is unstable and may spontaneouly explode
C. is flammable and will easily ignite
D. should be stored in an explosion proof cabinet
C. IS FLAMMABLE and will easily ignite
The red quadrant of the NFPA label indicates flammability, and a number 3 indicates that the liquid will easily ignite.
A biopsy that was placed in water by mistake is submitted to the laboratory. This mistake most likely will cause:
A. mushy sections
B. swollen and ruptured cells
C. hardening of the tissues
D. no appreciable changes
B. swollen and ruptured cells
Placing a specimen in water will cause the cells to take up water and swell and rupture as a result. Placing tissue in any hypotonic solution can have this effect.
The technique shown below is most likely the:
A. Schmorl
B. Grocott
C. Steiner
D. von Kossa
D. von Kossa
The Von Kossa (Calcium Stain) is intended for use in the histological visualization of calcium deposits in paraffin sections. This method is not specific for calcium itself but tissues are treated with a silver nitrate solution and the silver is deposited by replacing the calcium reduced by the strong light, and so can be visualized as metallic silver.
Unless the methyl green-pyronin procedure has been modified for formalin fixed tissue, which of the following fixatives will give the BEST results with this stain?
A. Bouin
B. Carnoy
C. Zenker
D. Zamboni
B. Carnoy
Carnoy fixed tissue is preferred for the methyl green-pyronin stain unless the procedure has been modified for formalin fixed tissue.
An employee complains of tingling or numbness in the hands, an aching neck, and shoulder and wrist pain. Referral to the health clinic would most likely reveal that the employee has:
A. bursitis
B. carpal tunnel syndrome
C. chronic repetitive trauma
D. range of motion inadequacy
C. chronic repetitive trauma
Chronic repetitive trauma is a cause of the symptoms mentioned.
One of the rare enzyme techniques that can be performed on paraffin sections is the:
A. naphthol AS-D chloroacetate esterase
B. succinic dehydrogenase
C. alkaline phosphatase
D. ATPase, pH 9.4
A. naphthol AS-D chloroacetate esterase
The naphthol AS-D chloroacetate esterase is one of the rare enzyme techniques that can be performed on paraffin sections.
Tissue antigens are irreversibly blocked by fixation in:
A. B-5
B. acetic zinc formalin
C. Bouin
D. glutaraldehyde
D. glutaraldehyde
Fixation in glutaraldehyde will irreversibly block tissue antigens.
Acid-fast bacilli may be demonstrated by staining with auromine-rhodamine and then examined with this type of microscope:
A. electron
B. darkfield
C. fluorescence
D. light
C. fluorescence
The auramine-rhodamine procedure uses a fluorescent dye to demonstrate the acid-fast bacilli, and must be examined with a fluorescence microscope.
The hazy blue nuclear staining results seen in the image below are most commonly seen when:
A. Celestine blue is used in place of hematoxylin
B. improper use of heat on the tissue processor
C. overstaining with Schiff reagent
D. fixation in Bouin solution
B. improper use of heat on the tissue processor
The hazy blue nuclear staining is the result of the use of heat in the tissue processor alcohol and xylene steps.
In the technique shown below, formaldehyde is used as a/an:
A. reducer
B. sensitizer
C. oxidizer
D. toner
A. reducer
Formaldehyde is used as a reducer in the diamine silver methods for reticulin.
The structures stained black in the image below can also be demonstrated with which of the following stains?
A. Gram
B. Congo red
C. Grimelius
D. periodic acid-Schiff
D. periodic acid-Schiff
The black stained structures are fungi and they can also be demonstrated with the periodic acid-Schiff technique.
In the Verhoeff-van Gieson technique, elastic fibers stain:
A. red to purple
B. blue-black to black
C. yellow to brown
D. blue to blue-green
B. blue-black to black
Elastic fibers stain blue-black to black in the Verhoeff-van Gieson technique.
The technique shown below depends upon the:
A. formation of aldehydes
B. presence of the carboxylate group
C. presence of the sulfate group
D. digestion with hyaluronidase
A. formation of aldehydes
The periodic acid-Schiff stain is shown in the image and the technique depends upon the formation of aldehydes.
