Phylum Apicomplexa
description
Transcript of Phylum Apicomplexa
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
In beetle
spores
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.
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 histolyticaAmebic 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