Protists Eukaryotes w/o tissue level of organization as in animals, plants, and fungi

Generalizations Most unicellular Organelles that are similar to eukaryote animals None have embryonic tissue layers as in animals

Classification of Protista: Excavata Diplomonadida = Giardia Kinetoplastida = trypanosomes Euglenida = Euglena Alveolata & Chromista Ciliophora = ciliates Apicomplexa = gregarines, coccidians Dinoflagellata = flagellates Opalinida = Opalina

Classification of Protista: Rhizaria Rhizopoda = amoebas Actinopoda = radiolarians Amoebozoa Lobosea = amoebas Opisthokonta Chlorophyta = Volvox

Support and Locomotion Plasma membrane Many have thickening = pellicle Or a test Pseudopodia, cilia, flagella

Nutrition Autotrophs = ? Heterotrophs = ? Or both Saprobic = take in dissolved stuff Holozoic = solid foods (food vacuole)

Reproduction Asexual and sexual Complex = parasites Binary fission

Budding Yeast

Sexual repro Production of gametes and then fusion = syngamy Isogamy = same size gametes Anisogamy = one larger Or conjugation

Phylum Euglenida Mostly freshwater, few marine, brackish Usually in habitat w/decaying organic matter

Support Pellicle = protein under cell membrane Stripes are seams in protein strips Flexible

Locomotion by flagella Two flagella, one usually shorter

Nutrition 1/3 have chloroplasts Positive phototaxis Photoreceptor near base of anterior flagellum

2/3 euglenids w/o chloroplasts = heterotrophs = phagocytosis Others can lose chloroplasts and switch Few parasitic forms Saprotrophic = take in dissolved nutrients

Euglenid reproduction Asexual by longitudinal cell division

Euglenida examples you need to know: Euglena Perinema

Other Euglenida? Phacus

+ Astasia Other Euglenida?

Phylum Kinetoplastida Trypanosomes, etc. ~ 600 species described Some free-living Trypanosomes strictly parasitic Digestive tracts of invert’s, phloem of plants, blood of vert’s

Trypanosoma cruzi life cycle: Chagas’

Reduviid = assasin bug

Other parasitic forms Leishmania: transmitted by sandflies Causes skin and mucous membrane infections in humans T. gambiense, others = sleeping sickness Tse-tse fly is intermediate host Tryps get into blood, then lymphatics and CS fluid

Support, locomotion Pellicle, glycoprotein protects outside Flagella: single, against side of cell nucleus kinetoplast kinetosome

Nutrition Mostly unknown in parasitic forms Free-living spp. are heterotrophic; capture bacteria with flagellum

Reproduction Asexual by longitudinal binary fission, budding Complex life cycles

Kinetoplastida you need to know! Leishmania

Infection occurs when infected sandfly regurgitates infective promastigotes into the blood while feeding. The promastigotes are phagocytized by macrophages and transform into amastigotes. The amastigotes multiply by binary fission in the macrophages. The life cycle is continued when a sandfly feeds on an infected person and ingests the amastigotes in the macrophages.

Leishmania Amastigotes in blood

Amastigotes in liver cells Leishmania

Trypanosoma lewisi Trypomastigote in vert. blood (infective form)

Phylum Ciliophora ~ 12,000 described species Common in benthic, planktonic communities Freshwater, marine, brackish Most are single celled

Mutualistic symbionts E.g., in goats, sheep Feed on plant material Some are parasites in fish gut, one in human gut

Support, locomotion Alveolar membrane system Underlying fibrous layer = epiplasm Cilia in rows; used in taxonomy More flexible for locomotion than flagella Beat in cone

Ciliophora you need to know: Didinium

Ciliophora Paramecium, Vorticella

Ciliophora Euplotes

Ciliophora Spirostomum