Protozoan Flashcards
(35 cards)
General characteristics of AMoeba
Characterized by the presence of hyaline foot-like extrusions
from the ectoplasm (pseudopods)
• Amoebas are very slow
• All amoebas are intestine dwellers except: E. gingivalis
All are commensals except: E. histolytica
Cyst is the infective stage except: E. gingivalis
From Phylum Sarcomastigophora (old), now Phylum
Amoebazoa
o Sarcomastigophora: combination of Sarcodina and
Mastigophora
§ Contains amoeba and flagellates
All amoebas are intestine dwellers except:
E. gingivalis
All are commensals except:q
E. histolytica
Cyst is the infective stage except:
E. gingivalis
Phylum Amoebazoa is formerly known as
Sarcomastigophora combination of Sarcodina and Mastigophora
Includes amoeba and flagellates
4 STAGES IN THE LIFE CYCLE
Trophozoite
Pre-cystic stage
Cyst
Metacystic stage
Trophozoite stage is
Vegetative Stage (feeding stage), motile stage, labile stage
Pre-cystic stage is
intermediary stage between trophozoite and cystic stage
Uninucleated
A trophozoite that firstly transformed into the cystic stage
Pre-cystic stage
CYSTIC STAGE is
Non-feeding stage, non-motile stage, resistant stage, infective stage
METACYSTIC STAGE is
Stage that will develop to become the trophozoite
Stage wherein the cyst is near becoming a trophozoite
Encystation
process when trophozoite transforms into a
cyst
Excystation
- process when a cyst transforms into a
trophozoite
False feet
Pseudopodium
T or F : a typical cyst, the nuclei found in the trophozoite is
almost the same as found in the cyst
True
Chromatoid bodies/Chromatoidal bars: are
aggregates of ribosomes
usually found in cysts
Only pathogenic intestinal amoeba
• Super diagnosed and under diagnosed:
E. histolytica
Most Pathogenic amoeba; true pathogen
E. histolytica
Pathogenicity of E. histolytica means
ability to cause invasive intestinal amoebiasis or Extraintestinal amoebiasis
Extraintestinal amoebiasis means
it can infect LIVER
Habitat, Final host, MOT of E. histolytica
Large intestine
Man
Ingestion of mature cyst
E. histolytica
Infective stage:
Virulent stage:
Infective stage: Cyst
Virulent stage: Trophozoite
Max nuclei of E. histolytica
4 nuclei (quadrinucleated / tetranucleated)
How to differentiate E. histolytica from E. dispar
only E. histolytica is hematophagous