Mycology Flashcards
are yeast or mold made up of differentiated tissue
mold
are all the cells of yeast or mold reproducible
yeast
fungi can be classified as __ or ___
yeast or mold
yeast reproduce through what method
binary fission
fungi use what type of respiration
aerobic
what is the function of hyphae
help disperse gametes of mold
hyphae are found in what organism
mold
what is found in fungi that acts similar to cholesterol, it which is helps stabilize the plasma membrane
ergosterol
what 2 components make up the fungal cell envelope
beta-glucans
mannoproteins
what is the effect of fungi having lots of mannose
mannose activates the mannose binding lectin pathway of complement
what are pseudohyphae
structures similar to hyphae but they are able to reproduce
in what organism will you find pseudohyphae
in what organism will you find hyphae
pseudo- yeast
hyphae- mold
what is the structure of septate hyphae
distinct walls between cells of mold
another name for a fungal spore is __
canidia
bacterial spores are very durable and are not easily killed. how does this relate to fungal spore
fungal are easily killed
what is the function of yeast showing bright colors
protection against ROS and UV light
when looking at a culture of fungi (mold) where would there be the highest concentration of canidia (spores), why
darker/bright pigmented areas
spores contain reproductive cells that would need protection against ROS/UV light
Pityriasis (tinea) versicolor, caused by __, causes __
malassezia furfur
benign skin color changes
tinea negra, caused by __, causes __
hortaea weneckii
benign skin darkening
black piedra, caused, by ___, causes __
piedra hortae
dandruff
onychomycosis, caused by __ and __, causes __
trichophyton rubrum
trichophyton mentagrophytes
nail fungal infection
how do superficial mycoses differ from cutaneous mycoses
superficial= benign
cutaneous= itch/burn in response to inflammation
what is a mycetoma
granulomatous inflammation beneath subcutaneous region to bone
what is a eumycetoma
granulomatous fungal growth that disperses granules when squeezed
what is the most common mycetoma
madurella
subcutaneous mycoses are often due to what 3 possibilities
-decreased profusion of blood to the area (ex: diabetic foot)
-continued exposure
-immunocompromised
what are endemic mycoses
fungal infections habitually present in a geographic area
why do fungi represent geographic areas
fungi live in soil so different areas have different soil types that allow for growth
what characterizes a primary pathogenic fungi
fungi able to cause disseminated disease in a healthy human
what does it mean to say all primary pathogens are dimorphic
they can switch between being a yeast or a mold depending on the temperature
what growth media is used exclusively for fungi
sabouraud dextrose agar
dimorphic fungi grow as yeasts at __C and mold at __C
yeast at 37C
mold at 25C
what are the 2 main stains used to visualize fungi
sliver
Calcoflour white
when using the calcoflour white stain to detect yeasts and molds, the fluorescent dye binds to __ in the fungal cell wall, making the fungi appear bright white
chitin
what fungi have yeast that are barrel shaped arthrospores connected by hyphae of mold
coccidiodes
what fungi have yeasts that can reproduce and form spherules (balls of yeast)
coccidiodes
what are 4 virulence factors of coccidiodes
secrete SOW glycoprotein
produce urease to neutralize phagolysosome pH
proteinase cleaves IgG, IgA, and collagen
receptor binds to mammalian estradiol and progesterone
what fungi causes valley fever
coccidiodes
what 3 populations are at greatest risk for valley fever caused by coccidiodes
pregnant/recently pregnant women
pacific islanders
african descent
what fungi appears as glassy with septate hyphae mold
blastomyces
where are blastomyces found
extracellular
what type of budding does blastomyces perform
broad budding
what yeast can cause slow spreading, elevated blue/purple painless warts
blastomyces
what glycoprotein does blastomyces shed
BAD1
BAD1 (secretes by blastomyces) and SOW glycoproteins (secreted by coccidiodes) have what 3 functions
distract macrophages
promote Th2 response (Th1 is needed)
soak up Ab and complement
what fungi have yeast found in or outside alveolar macrophages
paracoccidiodes
what type of budding do paracoccidiodes do
pilot wheel (parent cell with daughter buds that have their own buds)
what fungi can cause disseminated disease >40 years after initial infection, leading to painful periorbital, mucosal, and cutaneous lesions
paracoccidiodes
__ growth is promoted by estrogen
__ growth is inhibited by estrogen
coccidiodes promoted
paracoccidiodes inhibited
what are 2 virulence factors that paracoccidiodes has
alpha glucan instead of beta glucan in their cell walls prevents killing by neutrophils/macrophages
glycoprotein 43 allows for adherence to the basement membrane and promotes a Th2 response
what fungi mold form macroconidia and microconidia
histoplasmosis
where do histoplasmosis fungi grow
alveolar macrophages
what is the soil requirement needed for histoplasmosis to grow
soil rich in nitrates (nitrates are high in bird feces)
what fungi infection can lead to ulcers of the oral mucosa/tongue, cutaneous ulcers, and can also cross the blood brain barrier leading to meningitis
histoplasmosis
where is paracoccidiodes found
rainforest/lowland farms of central and south america
what fungi grows inside alveolar macrophages
paracoccidiodes
what yeast multiplies inside or outside alveolar macrophages
paracoccidiodes
what are the 3 virulence factors of paracoccidiodes
alpha glucan in cell wall prevents killing by neutrophils
glycoprotein 43 allow for adherence to host basement membrane
drive Th2 response (we need Th1)
what yeast growth is inhibited by estrogen
paracoccidiodes
what yeast can cause painful periorbital, mucosal, and cutaneous lesions after a latency of up to 40 years after initial infection
paracoccidiodes
what is the appearance of paracoccidioides yeast
pilot wheel (mother cell budding producing more buds)
how is sporotrichosis acquired
wound infection
sporotrix is most common in people who are working with __
garden soil
what yeast starts as a single lesion but can spread along lymph channels
sporothrix
potassium iodide can be used to treat what yeast infection
sporothrix
what is the appearance of sporothrix
narrow stalk with petal looking spores
are candida yeasts or molds
yeasts
what yeasts can form pseudohyphae from germ tubes
candida albicans
what yeast can be visualized with gram stain
c. albicans
what type of budding does candida albicans perform
budding from pseudohyphae
what yeast forms a germ tube
c. albicans