Phylum Apicomplexa Gregarines, Coccidians ~ 5,000 species All parasitic

Apical complex Organelles for attaching parasite to host cell Hooks/suckers

Plasmodium vivax Causes malaria Kills 1-3 million / year Mostly in Africa Vector = mosquito

http://www.cdc.gov/malaria/about/biology/

Malaria: important world-wide disease > 300-500 million infections / year > 1 million deaths / year Distinctive fever pattern – cyclic 48 hours

Gregarine: gut parasites of many invertebrates Best known from arthropods sporozoite

spores In beetle

Phylum Dinoflagellata ~ 4,000 species described Most unicellular, some are filamentous or colonial Some planktonic, some symbiotic (w/ corals, other cnidarians)

Red tide caused by dinoflagellates Discolored area of ocean with billions of dinoflagellates Produce toxins, kill everything.

Two flagella: armor or not Ceratium

Ceratium sp. 020_05ceratium414.jpg

Noctiluca

Dinoflagellates Freshwater and marine Osmoregulation by pusules Tubules that open to outside Autotrophic and heterotrophic Switch Many photo pigments

Repro Asexual Sexual: haploid cells divide, produce daughter cells = gametes Forms cyst, resting stage

Phylum Rhizopoda: amebas ~ 200 species Most free-living, some endosymbiotic, some pathogenic Pseudopodia in all

Entamoeba histolytica Amebic dysentery 4 nuclei - cyst found in fecal smear

Difflugia

Phylum Actinopoda ~4,240 species Radiolarians, Heliozoans, etc. Most w/internal siliceous skeletons Planktonic and benthic Heterotrophic mostly (phagocytosis) Binary fission, budding, sex rare

Actinopoda “ray feet” = axopodia Slender pseudopodia Actinosphaerium

Actinosphaerium

Foraminifera ~ 40,000 species All aquatic habitats Some planktonic, most benthic Tests form chalks, marble, limestone

Chalk cliffs of Dover

Phylum Diplomonadida Plasma membrane rigid from three microtubular roots Most phagotrophic, feed on bacteria Asexual, most form cysts

Giardia No mitochondria, ER, or Golgi bodies Warm climates mostly In severe infections every cell in gut is covered by a parasite. Coating of inside of intestine interferes with absorption

Giardia lamblia

Phylum Chlorophyta “Green algae” - green chloroplasts Like plants Some colonial Some have lost photosynthesis = heterotrophs

Volvox

Phylum Opalinida Many rows of cilia - different than in ciliates Reproduction is longitudinal (like flagellates), not transverse (ciliates) ~ 150 species Endosymbiotic in frog and toad gut

Phylum Opalinida Sexual repro by synamy Asexual = binary fission Opalina

Protist Phylogeny Origins ~ 2.5 bya Evolution of eukaryotes? Serial Endosymbiotic Theory (SET)

Serial endosymbiotic theory