Final - Spring Flashcards
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
