Lab I Exam: Mycology Flashcards
tinea barbae
beard
tinea captitis
scalp
tinea corporis
body
tinea cruris
groin (jock itch)
tinea faicei
face
tinea manum
hand
tinea pedis
foot (athlete’s foot)
tinea unguium
nail
What does the word “tinea” mean?
latin word for ringworm
Name the short lateral structure that will develop when certain yeast are incubated at 37 degrees Celsius in rich medium.
germ tubes
Name on yeast that is germ tube positive.
Candida albicans
At what temperature should chlamydospore agar be incubated?
room temperature - 25 C
Where should technologist look for spores on a chlamydospore agar plate?
What color and shape are they?
near the edge of the cover slip
blue and round
What is the principle of the India ink preparation?
take a drop of india ink with a drop of organism and view under high power; india ink particles will bounce off capsule and will see clear halo
What organism is India ink prep especially used for?
Cryptococcous neoformans
What type of specimen is most commonly used for India ink preps?
Spinal fluid
What reagent should be used for the examination of the reproductive structures of molds that are already growing in a culture?
LPCB- lactophenol cotton blue
What technique can be used to “save” wet preps for future use?
Wipe off excess LPCB from edges of coverslip, then seal with colorless fingernail polish; keeps in moisture
Name several media used for primary isolation of fungi.
Sab- Sabouraud's SDA - Sabouraud's dextrose agar Mycosel/Mycobiotic SabsC BHI- brain heart infusion for systemic fungus
Why would you incubate a culture for fungi at 25 degrees C and 37 degrees C?
Fungus may be dimorphic/diphasic; at 25 degrees it will grow in mold phase, at 37 degrees it will grow in yeast phase.
What term is used for fungi that grow differently at 25 and 37 degrees?
Dimorphic/diphasic
Why do mycologist use KOH? What specific protein does the reagent affect?
to clear, or dissolve, the keratious material from the body so fungal elements stand out; keratin
Name at least two fungal elements that could be seen in a KOH prep.
budding yeast pseudohyphae arthrospores blastospores septate hyphae aseptate hyphae
What is the difference between ectothrix and endothrix hair invasion?
ectothrix-invade outside/surface of hair shaft
endtothrix-invade hair shaft;dermatophyte
What genus of fungus causes ringworm?
Microsporum
Trichophyton
Epidermophyton
What genus of fungus exhibits dimorphism?
Blastomyces Coccidiodies Paracoccidiodies Histoplasma (genera are subcutaneous-sporothrix)
What genus of fungus is a frequent contaminant?
Aspergillis
Penicillium
What is a slide culture?
best way to observe fungi in the natural state
inoculate agar and place coverslip on it. fungi grows under coverslip, showing perfect morphology
