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111 Cards in this Set
- Front
- Back
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what type of nuclei do fungi have?
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eukaryotic with well defined membrane
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what are characteristics of a typical fungal cell?
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-mitochondria and endoplasmic reticulum in cytoplasm
-bilayered cell membrane -soft cell wall -some have polysaccharid capsule |
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where is the bilayered cell membrane foudn?
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the innermost layer of the cytoplasm
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what is the bilayered cell membrane made of?
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sterols such as ergosterol
*ergosterol is essential sterol in fugni |
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what is the soft cell wall composed of ?
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CHITIN and GLUCAN
also mannans, proteins, polsacc's and glycopeptides |
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what is recognized as an antigen?
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the cell wall
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what do fungi grow into?
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yeasts or molds
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what is yeast?
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single celled fungi
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what is mold
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multicellular filamentous colonies
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what is monomorphic?
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can occur as either a yeast or mold but not both
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what is dimorphic?
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can grow as yeast and mold froms depending on environmental conditions and temp
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what grows at body temp? yeast or mold?
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yeast
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what grow at room temp?
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mold
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what are ways of identifying fungi?
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-asexual spore morphology
-mode of formation -spore bearing mycelium -arrangement of their spores |
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what grows by longitudianl extension and produces spores in mold?
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hyphae
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what does mold form that is composed of clumps of intertwined branching hyphae?
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mycelia
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how are hyphae divided into individual cells?
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cross walls called septa
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what does septa have and what does this allow?
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spores through which organelles can move from one cell to another
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what are non septate hyphae with nuclei in a continuous mass of cytoplasm called?
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coenocytic hyphae
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what type of spore is a hyphal segment?
what are they formed by? |
arthrospores
formed by fragmentation of hyphae |
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what type of spre is a thick walled spore?
how is it formed? |
chlamydospore
formed terminally or within hyphal segment |
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what type of spre is formed at the tips of hyphae?
what is it known as if small? what is it knows as if large? |
conidiospores
small=microconidia lg=macroconidia (contain more than one spore) |
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what is a spherical sac like structure containing spores?
what type of spores does it contain? |
a sporangia containing sporangiospores
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so what are the 4 types of asexual spores in molds?
"A Sexually Creating Critters" |
1. arthrospores
2. chlamydosproes 3. conidiospores (micro and macro) 4. sporangia |
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what are the 5 types of vegetative mold structures
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1. flavic chandelier
2. knotted hyphae 3. pectinate bodies 4. racquet mycelia 5. spirals or coiled hyphae |
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what type of vegetative mold structures is a multiple branched hypahl end that resembles reindeer antlers or chandeliers?
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flavic chandelier structures
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what is a type of vegetative mold structure that consists of closely twisted entwine dhyphae forming nodular structures
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knotted hyphae
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what is a type of vegetative mold structure that has hyphal projections that look like broken combs?
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pectinate bodies
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what is a type of vegetative mold structure that are hyphae that look like a chain of tennis racquets?
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racquet mycelia
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what is a type of vegetative mold structure that are bedspring like helical coils found at the end of hyphae?
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spirals or coiled hyphae
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what are the four taxonomic phyla of medical importance?
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1. phylum ascomycota
2. phylum basidiomycota 3. phylum zygomycota 4. phylum deutermycota |
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what type of asexual spores (anamorphs) can fungi have?
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simple, single celled
or multicellular |
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what are sexual reproductive structures of fungi known as?
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telomorphs
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what isthe whole fungus known as?
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holomorph
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what phylum is the sac fungi?
how does is reproduce? how many ascospores are contained in an ascus? |
phylum ascomycota
reproduces with sexual reproduction that results in ascus (sac like structure) four to eight |
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what phylum is the club fungi?
how does it sexually reproduce? |
phylum basidiomycota
reproduces with basidiospores that are formed on a basidium (which is club shaped) |
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what phylum is the conjugation fungi?
how does it sexually reproduce? what is resistant to harsh environmental conditions? what are two types of sexual reproduction in this class? |
zygomycota
by simple copulation of tips of multinucleate hyphae forming large thick walled zygospores zygospores are resistant to environmental condition two types of reproduction include: 1. homothallic 2. heterothallic |
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what is homothallic sexual reproduction?
what is heterothallic sexual reproduction |
homo=cells of single colony engage in reproduction
hetero=two different colonies engage in sexual reproduction |
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what phylum is the only one to reproduce asexually?
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deuteromycota
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what does deteruomycota fungi produce?
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conidia
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what are fungi characteristics of replication concerning:
hosts? energy? products of excretion? habitats |
grow as saprophytes(live on living or dead organisms?
are heterotrophs(can't make own energy) excrete extracellular enzymes to digest food outside of fungal cells habitats include air, water, soil, plants and animals |
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what type of lab environment grows fungi?
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Sabourauds dextrose agar at 25-37 degrees C
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how long to fungal colonies take to cultivate?
what is growth aided by? |
4-6 weeks
presence of antibiotics |
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what is the primary method of dissemination?
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asexual spores
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what are the three types asexual methods of fungal reproduction?
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1. budding
2. spore formation3. fragmentation |
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what does mold form that is composed of clumps of intertwined branching hyphae?
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mycelia
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how are hyphae divided into individual cells?
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cross walls called septa
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what does septa have and what does this allow?
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spores through which organelles can move from one cell to another
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what are non septate hyphae with nuclei in a continuous mass of cytoplasm called?
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coenocytic hyphae
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what type of spore is a hyphal segment?
what are they formed by? |
arthrospores
formed by fragmentation of hyphae |
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what type of spre is a thick walled spore?
how is it formed? |
chlamydospore
formed terminally or within hyphal segment |
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what type of spre is formed at the tips of hyphae?
what is it known as if small? what is it knows as if large? |
conidiospores
small=microconidia lg=macroconidia (contain more than one spore) |
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what is a spherical sac like structure containing spores?
what type of spores does it contain? |
a sporangia containing sporangiospores
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so what are the 4 types of asexual spores in molds?
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1. arthrospores
2. chlamydosproes 3. conidiospores (micro and macro) 4. sporangia |
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what are the 5 types of vegetative mold structures
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1. flavic chandelier
2. knotted hyphae 3. pectinate bodies 4. racquet mycelia 5. spirals or coiled hyphae |
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what type of vegetative mold structures is a multiple branched hypahl end that resembles reindeer antlers or chandeliers?
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flavic chandelier structures
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what is a type of vegetative mold structure that consists of closely twisted entwine dhyphae forming nodular structures
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knotted hyphae
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what is a type of vegetative mold structure that has hyphal projections that look like broken combs?
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pectinate bodies
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what is a type of vegetative mold structure that are hyphae that look like a chain of tennis racquets?
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racquet mycelia
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what is a type of vegetative mold structure that are bedspring like helical coils found at the end of hyphae?
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spirals or coiled hyphae
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when does asexual sporulation of yeast occur in asexual reproduction?
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a process called buddingproduces blastospores
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what are long chains of elongated yeast cells called that are assoc with asexual reproduction?
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pseudohyphae
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what is it called when individual cells ufse their membranes and exchange genetic info
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conjugation
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what types of mutations can occur
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point mutations
deletions |
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what is conversion?
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the transfer of a genetic sequenced from one chromatid to a homologous chromatid during meiosis
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what is inversion?
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when the segment b/w two breaks is reinserted in reversed orientation in the same chrmosome
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what is translocation?
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when a segment is removed and transferred into another chromosome
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what is complementation?
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when polypeptides from two mutants repair each other when they bind together
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fungi are considered chemoheterotrophic. what does this mean?
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they obtain carbon compounds from non living organic material as saprophytes or
from living tissue as symbionts |
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what are two types of pathogenic symbionts and describe each.
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1. necrotrophic=facultative pathogens that live on damaged tissue and usually bring death to host
2. biotrophic=obligate pathogens that are dependen on living host tissue |
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what are fungal virulence factors?
what effects on host cells do the virulence factors have? |
fungi virulence factors are a variety of enzymes
can: 1. damage host celll 2. lyse host cell 3. suppress antifungal host defense |
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what acts as a fungal allergen?
what type of formations do they cause? |
toxins act as allergenx
they cause granuloma formations |
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what glycoprotein of fungal cell walls is a virulence factor?
what effect does it have? |
mannan
it suppresses lymphoblast formation and inhibits lymphocyte proliferation it also inhibits keratinocyt proliferation by slowing epidermal turnover and allowing for a more persistent chronic infection |
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what is the determinant of virulence?
based on this determinant which type of fungi are considered virulent? if a fungi lacks invasive enzymes can it be virulent? |
growth rate determines virulence
normal growth rate is virulent lower growth rates arent lacking inivasive enzymes it cannot be virulent |
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what are ways to disinfect fungi?
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1. freezing at 0 centigrade
2. desiccation 3. soaps and detergents 4. lyophilization |
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what does freezing do?
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it inhibits fungal metabolism
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what does dessication do?
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it inhibits fungal metabolism
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what do heavy metals, chlorine, alcohol, phenol and formaldehyde and ehtylen oxide and peroxide do to fungi?
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kills most fungal forms by denaturing proteins
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what effect does freezing have on vegetative and spores?
desiccation? |
freezing does not kill vegetative forms of spores
desiccation kills most vegetative forms but NOT spores |
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what effect do soaps and detergents have?
what effect does lyphophilization and freeze drying have? |
soaps etc damage cell membranes and kill most fungal forms
lyophilization and freezy drying inhibit fungal metabolism and allow long term storage of cultures |
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what are ways to Sterilize fungi?
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1. ionizing radiation
2. autoclaving 3. incineration |
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what effect does ionizing radiation have?
what effect does autoclaving have? what effect does incineration have? |
destroys DNA and kills most fungal forms
autoclaving kills ALL fungal forms by denaturing proteins incineration destroys ALL fungal forms |
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what is autoclaving process?
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121 centigrade for 15 minutes
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what are three diagnostic tests for fungi?
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1. KOH
2. Periodic Acid-Schiff rxn 3. Giemsa stain |
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why is KOH used commonly?
what does KOH do to fungi? |
it is quick and inexpensive way to view clinical specimans for presence of fungi
the KOH causes most tissue elements to become dissolved leaving fungal elements such as conidia or hyphae that retain shape, color and can be seen with light microscopy |
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what is the Periodic acid-schiff rxn (PAS)
what fungal element in particular is stained? |
has aldehyde groups that bind to basic fuchsin and stain the fungal elements red
polysaccharides found in the cell walls are stained |
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what is the giemsa stain?
when is it used? |
stains tissue and blood cells showing blue-colored intracellular yeasts
used when intracellular structures are to be examined |
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what are some compounds that inhibit DNA fxn?
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1. flucytosine
2. griseofulvin 3. pentamidine isethionate |
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what compound that inhibits DNA interferes with pyrimidine metabolism?
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flucytosine
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which compund that inhibits DNA inhibits fungal cell mitossis at metaphase by interaction w/ microtubules resulting in disruption of mitotic spindles?
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griseofulvin
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which compound DNA by interfering with nuclear metabolism by inhibiting DNA, RNA, phospholipids and PRO synthesis
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pentamidine isethionate
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what are compounds that change fungal membrane permeability?
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1. amphotericin B and nystatin
2. Fluconazole, itraconazole, ketconazole, miconazole, thiabendazole |
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which of the compounds that change membrane permeability does so by binding to ergosterol in cytoplasmic membrane?
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amphtericin B and nystatin
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which compounds that change membrane permeability inhibit ergosterol sythesis by preventing conversion of lanosterol to ergosterol in the cytoplasmic membrane?
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the azoles
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what are the superficial mycoses?
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1. Malassezia(versicolor)
2. Hortaea(Tinea Nigra) 3. Trichosporon(White Piedra) 4. Aspergillus, Penicillium, Mucor, Rhizopus(OTO parm) |
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what does Malassezia cause?
what does Hortaea cause? |
Malassezia=pityriasis versicolor
Hortaea=Tinea Nigra |
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what does trichosporn cause?
what does aspergillus, penicillium, mucor and rhizopus cause? |
white peidra=trichosporon
aspergillus etc=otomycosis |
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what are cutaneous mycoses?
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1. tichophyton
-tinea faciei -tinea barbae -tinea cap endo 4.microsporum, trichophytoon=tine cap ecto 5. trichophyton epidermophton: -unguim -cruris -pedis trichophyton, epidermophyton, microsporum: -corporis -manuum |
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what does Trichophyton alone cause?
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either:
a. Tinea faciei b. Tinea barbae c. Tinea captitis-endothrix |
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what causes tinea captis-ectothrix?
what causes tinea corporis? |
capitis ectothrix=microsporium, trichophyton
corporis=epidermophyton, microsporum, trichophyton |
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what does epidermophton, microsporium and trichophtyon cause?
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either tinea corporis or tinea manuum
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what does epidermophyton trichophyton cause?
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tinea crusis and tinea pedis
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what are subcutaneous mycoses?
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1. Pseudaliescheria Madurella
2. Sporothrix |
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what does Pseudallescheria Madurella cause?
what does sporothrix cause? |
1. Pseudallescheriasis
2. sporotrichosis |
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what are opportunistic yeasts?
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1. candida
-candidiasis 2. rhodotorula -rhodotorulosis 4. Pneumocystis -PCP 5. Crytopcoccus -Cryptococcosis |
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what does candida cause?
what does candida, rhodotorula and saccharomyces cause? |
1-candidiasis
2. Rhodotorulosis |
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what does Pneumocystis cause?
what does cryptococcus cause? |
pneummocystis=pneumocystosis
crytpococcus=crytococcosis |
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what are opportunistic molds?
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1. aspergillus
2. Geotrichum 4. Arthroderma 5. Candida 4. Scopulariopsis 5. Onychomysosis 6. Absisia 7. Mucor 8. Rhizopus |
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what does aspergillus cause?
what does geotrichum cause what does absidia, mucor, rhizopus cause? |
aspergillus=aspergillosis
geotrichum=geotrichosis absidia,mucor, rhizopus=mucomycosis |
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what are systemic fungal infections?
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1. Blastomyces
2. Coccidioides 3. Histoplasma |
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what does Blastomyces cause?
what does coccidoides cause? what does histoplasma cause? |
1. blastomycosis
2. coccidioiomycosis 3. histoplasmosis |
