The weird, Wacky, wonderful world of… Kingdom Protista! Animal-like Animal-like Protists Plant-like Plant-like Protists Fungus-like Fungus-like Protists

What is a protist?? Kingdom Protista is a dumping ground for organisms that don’t fit into any other Eukarya kingdoms – Eukaryotes – Unicellular or colonial – Lots of different life styles – Live in most environments – Categorized by nutrition

Autotrophic Protists Algae (singular: alga) Photosynthetic –Produce most of the oxygen in the atmosphere! No roots, stems, or leaves 4 phyla: –Euglenaphytes (no cell wall; can be heterotroph in low light) –Diatoms (patterned silica shells) –Dinoflagellates (cause of red tides and bioluminescence; some are heterotrophs) –Red, Brown, Green algae Green algae were likely ancestral plants

Euglena Dinoflagellates Diatoms Volvox Chlamydomonas Pediastrum

Volvox

A close-up of Volvox cells within the colony; 2 flagella and red eyespot are visible

Diatom cell wall is made of silica (like glass)

Bioluminescent Dinoflagellates

Red tides caused by toxic dinoflagellates. This red tide killed some fish.

Giant kelp are multicellular brown algae!

Fungus-like Heterotrophic Protists Saprotrophs (feed on dead organisms or live as plant parasites) Unlike fungi, they can move! 3 phyla: –Cellular Slime Molds –Plasmodium Slime Molds –Water Molds

Dog Vomit Slime Mold Slime molds creep by amoeboid movement – can move as much as 2.5 cm/hour!

Water mold growing on a dead mayfly larvae

Animal-like Heterotrophic Protists Proto = first; zoa = animals (singular: Protozoan, plural: protozoa) Unicellular Heterotrophs 4 phyla (mostly grouped based on method of movement) –Ciliates –Flagellates –Amoeboids –Sporozoans

Ciliates & Flagellates Ciliates –Use cilia for movement –Not parasitic –Example: Paramecium Flagellates –Use flagella for movement –Some parasitic, e.g.,… Trypanosoma (African sleeping sickness) Giardia lamblia –Some mutualistic, e.g.,… Trichonympha (help termites digest wood) Giardia lamblia

ParameciumTrichonympha Cilia

Trichomonas vaginalis: an STD

African Sleeping Sickness (Trypanosoma)

Amoeboids Move via pseudopod ("false foot") –Pseudopods: Cytoplasm-filled projections Engulfs food by flowing around it Examples –Entamueba histolytica (amoebic dysentery) –Foraminifera (CaCO 3 shell) –Amoeba Entamueba histolytica Foraminifera Amoeba

Sporozoans –Parasitic; live inside a host –Cannot move on their own –Examples: Plasmodium falciparum (malaria), Toxoplasma gondii (toxoplasmosis) PlasmodiumToxoplasma

Malaria in red blood cells