Final - Spring Flashcards
(29 cards)
cyst
thick walls
resistant
resting cell
trophozoite
active, feeding, multiplying stage of MOST protozoa
oocyte
zyogotic cyst
schizogony
asex reproductive stage of apicomplexan parasite (sporozoite)
multiple fission:
- nuc divides first and then cell divides into as many parts as there are nuc
vector
living org that carries disease-causing org to NEW host
int-med host
hosts immature stages
- larvae
- asexual
definitive host
mature sexual parasite
protozoa morphology
- typ euk org-lls
- memb-bound nuc with chr
- cytoplasm:
- endoplasm: inner layer, more fluid with granules
- ectoplasm: outer layer, more viscous, clear
- moist environments
- heterotropic: nutrients from environment
- cytostome mouth to ingest food
protozoa motility
- crawling
- pseudopodium: attach and pull via actin and myosin
- flagella/cilia
- gliding
- apicomplexans
protozoan reprod
asexual:
- binary fission: budding
- multiple fission: segmentation
- **several rounds of replication WITHOUT cytokinesis –> multinuc cell –> multiple progency simul
- can be done by all protozoans
sexual: gametes - ONLY APICOMPLEXANS
helminths
multicellular worms
complex reprod: inter-med/definitie hosts
tough acell cuticle/tegument
elab attachments struc
ingest host tissues/fluid for E
flukes
trematodes
leaf-shaped adult flatworms
- except schisto = cylindrical
2 suckers:
- oral (blind pocket alimentary tract)
- ventral suckers (attachment)
hermaproditic, except blood = dioecious
intermed hosts = mollusks (snails and clams)
cestodes
tapeworms
- larvae:
- cystic/solid
- extraintestinal tissues
- adult:
- elongated/segmented
- hermaphroditic
head/scolex: 4 muscular cup-shaped suckers or hooklets
indiv seg = proglottids (distal = uterus of eggs)
- chain = strobila
nematodes
roundworms
- adult in intestines
- eggs in feces
- Sarcoptes scabiei ‘mite’ with skin rashes (scabies)
- Pthirus pubis louse with hair infestation (crabs)
Immunity to Parasites
•Innate:
- •Protozoa- phagocytes
- •Helminth- eosinophils
•PAMPS
- •GPI anchors, hemazoin, mannose-rich sugars: Protozoa
- •Lipoproteins: some helminths
- •PRRs: collectins, pentraxins, C-type lectins, scavenger receptors, Complement receptors
•Adaptive: widely varied
Cystoisospora belli
ingestion of elliptical oocytes from environment: common in warmer climates
- commonly assoc with HIV and immunosuppression
- severe watery diarrhea
dx: acid fast or fluorescent staining
tx: TMP-SMX
Balantidium coli
- cyst:
- distinct wall
- large macronucelus
- trophozoite:
- VERY large
- rows of cilia (fuzzy appearance)
- invades colon
- ab pain, watery stool
- resevoir:
- cow, pigs, horse, swine: farmers
- fecal-oral
- dx: stool, mucosal scrap during colonoscopy
- tx: tetracycline, metro
Trichuris trichiura
whip worm
fecal-oral
symptoms:
- dysentery, rectal prolapse, dev deficits
- NO eosinophilia
dx: fecal smear
tx: albendazole
yeast
unicellular: round or ovale
budding (blatoconidia) or fission
- daughter cell can form pseudohyphae (sausage-like)
round, pasty, mucoid colonies on agar
mold
multicell: hyphae (threadlike tubular struc)
- types:
- septate
- non-septate/coenocytic: multinuc without division
- aerial hyphae:
- fuzzy outgrowths above surface of agar
- mycelium = networks of branched hyphae
dimorphic fungi
mold in environ –> yeast in body for infection
reprod of fungi
conidospores (conidia)
- asex - formed off end of hyphae
- unicellular/multicell spore NOT enclosed in sac
arthrospores (arthroconidia)
- asex - formed by frag of septate hypahe into single cells
blastospores (blastoconidia)
- asex - “buds” from parent yeast
sporangiospores:
- asex - endospores inside spherules (sporangia) in tissues
mycoses types
superficial:
- infection on dead skin cells, hair shaft
- no cell response
- cosmetic only
cutaneous:
- infect kera-stratum corneum: LIVING TISSUE NOT INVADED
- symp: percut absorption of metabolites
- inflam
- DTH
subQ:
- implantation: LONG period of time to adapt –> chronically progressive
systemic: true pathogens: - virulent, mostly self-resolving
- req inhal of LARGE dose
- termal dimorphism
- geographic niches
opportunisitic: immunocompromised or altered normal flora
