Protozoans

• Protozoa


  • unicellular
  • single-celled organisms
  • most commonly found in the lower gastrointestinal tract
• Protoplasm


  • nucleus + cytoplasm
  • unit that performs vital function of protozoa
• Cytoplasm


  • consists of thin outer ectoplasm and inner endoplasm
  • surround nucleus
  • for nutrition and reproduction
• Locomotor apparatus


  • used for movement
• Locomotory apparatus : Pseudopodia


  Locomotory apparatus of Amoeba
• Locomotory apparatus : Flagella


  Locomotory apparatus of Flagellates
• Locomotory apparatus : Cilia


  Locomotory apparatus of Ciliates
• Periostome


  part of the cell where the food passes
• Cytopyge


  cell anus / excretory vacuole
• Trophozoite


  • vegetative
  • motile
  • infective
  • found in fluid or watery stool and soft or semi-formed stool
  • irregular in shape
  • usually one nucleus
• Encystation


  • process that enters cyst stage
  • development of cystic stage
• 2 types of encystment

  • protective
  • reproduction
• Excystation


  • exit the cyst stage
  • development of trophozoite stage
• Cyst


  • non-motile
  • resistant stage
  • round/oval shaped
  • seen in formed stools
  • often with more than one nucleus
• Type of reproduction of Protozoa

  • asexual (simple fission) -> division of nucleus
  • sexual (union of 2 cells - syngamy) -> union or conjugation
• 3 Phylum under Protozoa

  • Phylum Sarcomastigophora
  • Phylum Ciliophora
  • Phylum Apicomplexa
• 2 Subphylum under Phylum Sarcomastigophora

  • Subphylum Mastigophora
  • Subphylum Sarcodina
• Locomotory organelle : Flagella

  • Subphylum Mastigophora (Flagellates)
• Locomotory organelle : Pseudopodia

  Subphylum Sarcodina - Amoeba
• Locomotory apparatus : No locomotory organelle

  Phylum Apicomplexa
• Entamoeba gingivalis


  all Amoeba inhabit large intestine except?
• Entamoeba gingivalis and Dientamoeba fragilis


  All Amoeba develop cyst stage except?
• Entamoeba histolytica


  all Amoeba are commensals except?
• Pseudopodia

  • hyaline foot-like projections
• 2 forms of E. histolytica

  • E. histolytica (magma form)
  • E. hartmanni (minuta form)
• Entamoeba histolytica (magma form)


  • large race
  • pathogenic
• Entamoeba hartmanni (minuta form)


  • small race
  • non-pathogenic
• Entamoeba


  delicate nuclear membrane and small karyosome
• Endolimax


  irregular nucleus and large karyosome
• Iodamoeba


  fairly large karyosome and periendosomal granules and radiating achromatic fibrils
• Dientamoeba


  karyosome splits into 4 or more fragments
• Entamoeba histolytica


  • round cyst
  • 1-4 nuclei
  • sausage-shaped or agar shaped chromatoidal barr
  • it has "ingested RBC"
• What parasite is this? Entamoeba histolytica

  
• Charcot-Leyden Crystals


  • kasama lagi ni E. histolytica
  • product of eosinophils
  • bright red in trichrome staining
• Entamoeba dispar


  • indistinguishable from E. histolytica
  • considered as subspecie of E. histolytica
  • difference: RBC inside troph of E. histolytica
  • described by Brumpt
• Entamoeba moshkovskii


  • indistinguishable from E. histolytica and E. dispar
  • 3rd subspecie of E. histolytica
  • 1st described in Moscow sewage
• Entamoeba hartmanni


  • small race E. histolytica
  • very similar to E. histolytica but smaller
  • "ingested bacteria" troph
• Entamoeba coli


  • oval
  • 1-8 nuclei
  • with broomstick or splinter-like ends chromatoidal barr
• Entamoeba gingivalis


  • 1st parasitic amoeba of humans to be described
  • recovered from soft tartar
  • oral parasite
  • no cyst stage
• Entamoeba poleckii


  • found in intestines of pigs and monkeys
  • Highest prevalence in Papua New Guinea