Exam 2 - Exam 2 Apicomplexians I Spore-Forming Protozoa...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Exam 2 Apicomplexians I – “Spore-Forming Protozoa - Phylum Apicomplexa characteristics o Parasites o Apical complex Consists of polar rind, conoid, rhoptry, micronemes, subpellicular tubules, and micropore All disappear after penetration of host cell – except micropore Found in sporozoite and merozoite stages o “Spore” stage involved in Transmission o Alternate asexual and sexual reproduction o Several pathogens in this group - Terms o Schizogony – multiple fission; where one becomes many; asexual reproduction in which multiple nuclear divisions take place followed by one simultaneous cytokinesis resulting in many daughter cells produced at once Merogony – multiple fission produces many daughter cells called merozoites (same thing as schizogony; one becomes many) o Merozoite – daughter cells produced from schizogony/merogony which will asexually reproduce to produce more merozoites o Meront – another term for the cell that undergoes merogony (schizogony) It will contain merozoites o Schizont – analogous term meaning the cell that undergoes schizogony, but cytokinesis is not complete o Gametogony – merozoites or trophozoites maturing and differentiating to form gametocysts by multiple fission; divisions will now produce gametes (sex cells) o Macrogametocyte – will produce female gamete(s) “ macrogametes o Microgametocyte – will produce male gametes “ microgametes” (only flagellated stage in this group); analogous to sperm o Zygote – a cell produced by fusion of macrogamete and microgamete o Oocyst – a zygote that has secreted a resistant outer hyaline membrane around itself Has resistant membrane around it (coccidian, e.e. Eimeria) Needed because sporogony must occur outside of the host Requires oxygen for sporogony to occur Cystic form that results from sporogony, may ( Eimeria) or may not ( Plasmodium) have hard, resistant membrane o Sporogony – multiple fission of zygote; aka a sporont o Sporocyst – stage of development of a sporozoan protozoan, usually within the oocyst
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
o Sporozoite – daughter cell resulting from sporogony * BLUE ONES ARE COMMON TO ALL APICOMPLEXANS - Class Coccidia o Family Eimeriida Eimeria spp Isospora belli pathogen Cyclospora cayetanesis pathogen o Family Cryptosporidiidae Cryptosporidium pavrum pathogen o Family Sarcocystidae Toxoplasma gondii pathogen Sarcocystis spp - Three phases of life cycle o Schizogony/merogony o Gametogony o Sporogony – Occurs outside of host (usually) o Sporozoite – infective stage of parasite Contained within the sporocyst inside the oocyst - Oocyst Morphology o Picture of Eimeria oocyst (4 sporocysts with 2 sporozoites each) o Picture of Isospora oocyst (2 sporocysts with 4 sporozoites each) * Unsporulated oocysts: NOT infective!! * Can’t use oocyst and cyst interchangeably – not the same thing!
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 10/28/2008 for the course BIOL 4105 taught by Professor Farrar during the Spring '08 term at LSU.

Page1 / 38

Exam 2 - Exam 2 Apicomplexians I Spore-Forming Protozoa...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online