Eating habits - 5th set Flashcards
fungi
They are heterotrophs and saprophytes; some are parasites Cell wall made of chitin (target for antifungal agents) is present.
Fungi prefers to grow..
in acidic pH ( 5 or lower ) with high salt and sugar in slight moist environment and relative humidity of 70 % or more
fungi have a filamentous…
body (mycelium); individual filament is called hypha (plural - hyphae)
The hyphae are well adapted to..(eating - sick - kitchen table)
absorb food –high surface to volume ratio –releases enzymes to breakdown food; also acts as a repellant
Vegetative hyphae
segment of hyphae which obtains nutrition
Aerial hyphae
projects above the surface; bears reproductive spores
Specialized hyphae includes
haustoria and rhizoids
Dimorphic fungi can grow as…
yeast like ( unicellular ) or as mycelia
2 classes of hyphae
depending on the presence of septa ( cross wall ) In some, individual cells are separated from one another by septa (septate hyphae vs coenocytic hyphae )
All fungi have lysosomes
-digest damaged cells -helps parasitic fungi to invade host
Fungi have unusual reproductive modes
Sexual as well as Asexual produces spores. Asexual or sexual spores germinates, develop into new hyphae and mycelium
antifungal drugs target
Affects / targets membrane component
Azoles
includes Clotrimazole, Miconazole, Fluconazole FYI -inhibits ergosterol synthesis ; interfere in the synthetic pathway-active component of medications (over the counter) to treat localized, superficial yeast infection
Antifungals that target cell division (grease - couch)
Gresiofulvin (synthesized by some fungi)-exact mechanism, unknown-thought to interfere with spindle fibers component microtubules during polymerization/depolarmerization; blocks mitotic events used for nail and skin fungal infection treatment.
Antifungal - Nucleic acid synthesis (kitchen counter - cite-o-sine)
poor target. Flucytosine: taken by yeast cell’s permease and converted into active, inhibitory form, 5 fluorouracil ( inhibits nucleic acid synthesis )
hetro means…
different carbon and energy sources.
facultative anaerobes (flex) and ex.
flexible in their oxygen requirement. ex. - yeast (candida)
sabarouds fungi medium
high salt and sugar, and acid ph unique.
hyphae…(1)
1 filament from hairlike fungi body
hyphae are…(noe)
one hyphae close by will release repellants will signal other hyphae to move to different area for nutrients.
part of hyphae on top of and under bread..
bread, called arial hyphae. usually has reproductive cells. part under, in bread - called vegetative hyphae
parasitic
grows on sikin called haustoria, they are gentle in their actions. others are rhizoids, feeds off dead organic matter, much more aggressive.
fungi are…(missed question)
natural decomposers, act upon dead organic matter and recycle most elements to the atmosphere or environ.
most that infect us are…(diana)
dimorphic. oval shaped. dimporphic that grow on us - that means morphology is based on temperature (environment).
when outside they have one form, but inside body have a different form.
in coenocytic hyphae, no…
no septa and cells are multinucleated
food moves to all…
all cells in fungal body
most that infect us are…
diamoprhic
cellular resources are (nose)
nutrients to septae
point of growth are…
tops of cells of ariel hyphe
fungi secretes…
keratinase to help it go deeper into the host.
reproduction is…(always)
sexual as well as asexual - always produce spores.
difference btwn bacteria
fungal spores can be destroyed by heat, and 2) fungal spore is mainly for multiplication, but bacterial spore is not for multiplication
mycelium
has male and female hyphae
hetrokaryotic (sexual reprod) (skeleton corner)
also called dikaryon - when there are 2 nucleus within a cell. it can undergo reproduction a few times by itself.
zygote (sexual reprod)
zygospore, 2N chromosome. will get transformed into spore producing structure called fruiting bodies.
meiosis (#) (sexual reprod)
becomes N # of chromosome
conidium and sporangium
fruiting bodies. will release spore and germinate, blown by wind or inhaled. germinate then cause fungal infection. specifically sexual repro.
asexual makes..
spore producing structure
fungal plasma membrane has (membrane - bedroom)
sterols like other eukaryotic cells, besides phospholipids and proteins. most bacteria do not have cholesterol or sterol, but cell wall instead. sterol is called ergosterol.
antifungal drugs targets (same)
membrane component = erogosterol of fungi membrane
azoles
superficial yeast infection or fungal
fungal cell wall is (glue)
fungal cell wall is chitin, it is made up of sugar. glucan sythase are involved in chitin synthesis.
aspergillosis
lung infection
Gresiofulvin (grease 2) - no oral…
because stomach epithelial are constantly turning over. no IV, the bone marrow blood cells have limited life span and cont. turnover of blood cells
fluorouracil (kitchen floor)
stops DNA sythesis, only effective for yeast. incorporated into DNA.
Azole blocks..
ergosterol, which is needed for stability of cell membrane.
majority of fungi are…(ana - lamp)
aerobes or facultative anaerobes (can switch to fermentation if O2 is absent) ( Ex. yeast) –few are obligate anaerobes - found in cattle’s and deer’s intestine
Haustoria (opposite)
are associated with parasitic fungi
Rhizoids are…
are associated with saprophytic fungi
septa have (fingers)
microscopic openings -mobilizes cellular resources right to the point of growth
septate hyphae (x)
cross wall
coenocytic hyphae (many co-ed)
no septa - cells are multinucleated
anti-fungal drugs - Polyenes (poly w/ nya - cat tree)
includes Amphotericin and Nystatin-binds to ergosterol component ; forms pores results in leaky membrane -very toxic; limited use in life threatening conditions
Saprophytes feed off…
of dead cells.
dikaryon stage (skelton bedroom)
nucleus fuses - 2N. Fruiting bodies that contain spores. break apart and spores are released
Echinocandins - antifungal
used for Candida and Aspergillosis treatment-interferes with fungal cell wall synthesis inhibiting glucan synthase - involved in chitin synthesis. when chitin is compromised, there is no cell wall.
trophs means
nutrients. Fungi use carbon from sugar, amino acids.
human pathogenic fungi are
dimorphic ( thermally dimorphic)
obligate anaerobes
can’t tolerate atmospheric oxygen
