Domain Bacteria Domain Archaea Domain Eukarya Common ancestor Kingdom: Protists Domain Eukarya

General characteristics Classification criteria Classification criteria –eukaryotes –not animal, plant or fungi –Live in wet or moist environments That’s more of what they’re not & not what they are!

Great Diversity dinoflagellates & ciliates euglenoids brown algae & diatoms red algae green algae miscellaneous?

Protist Diversity The full spectrum of modes of life The full spectrum of modes of life –from unicellular to multicellular –autotrophic to heterotrophic –asexual to sexual reproduction –pathogenic to beneficial –sessile to mobile

Protist Motility How they move: How they move: –flagellum –cilia –pseudopod

Kingdom Protista is REALLY Diverse: We will divide & learn them in three- groups: We will divide & learn them in three- groups: –Animal-like –Plant-like –Fungus-like

Animal-like Protists Aka Protozoans Aka Protozoans –heterotrophs, predators –Unicellular Amoeba Amoeba Paramecium Paramecium Stentor Stentor Paramecium with food vacuoles stained red Amoeba ingesting a Paramecium

Plant-like Protists Plant-like Protists Plant-like Protists –autotrophs, photosynthesis –Unicellular or multi-cellular Euglena Euglena Algae (green, red, brown) Algae (green, red, brown) Diatoms Diatoms Dinoflagellates Dinoflagellates

Fungus-like Protists Fungus-like Protists Fungus-like Protists –Heterotrophs –Motile at some point in life cycle –Reproduce by forming spores Water molds Water molds Downy Mildews Downy Mildews Slime molds Slime molds

Benefits of Protists Plankton Plankton –phytoplankton small algae + diatoms small algae + diatoms much of the world’s photosynthesis much of the world’s photosynthesis produces ~90% of atmospheric oxygen produces ~90% of atmospheric oxygen –zooplankton heterotrophic protists + animals heterotrophic protists + animals key ecological role at base of marine food web key ecological role at base of marine food web Mmmmmm! Sounds like breakfast!

Benefits of Protists Plankton Plankton –Food for humans Kelp (brown algae or “sea weed”) Kelp (brown algae or “sea weed”) Used to thicken foods such as ice cream or jelly Used to thicken foods such as ice cream or jelly –Abrasives Diatoms (silica shells *glass) Diatoms (silica shells *glass) Empty shells form thick deposits that can be used for commercial items such as pool filters, toothpaste, sparkling paint Empty shells form thick deposits that can be used for commercial items such as pool filters, toothpaste, sparkling paint –Also natural pest control for slugs & fleas

Protists can also be Harmful Phytophthora infestans Phytophthora infestans Great Potato Famine Great Potato Famine –killed nearly a million people in Ireland in 1846–1847 –water mold virtually wiped out the country’s potato crops, which were an essential staple in the Irish diet (sometimes the only food on the table.).

Red Tides occur when enormous blooms are triggered by an upwelling of nutrients from the water’s depths during warmer seasons. Red Tides occur when enormous blooms are triggered by an upwelling of nutrients from the water’s depths during warmer seasons. Population can jump to more than 20 million cells per liter of sea water along some coasts during these blooms, turning the water a reddish hue. Population can jump to more than 20 million cells per liter of sea water along some coasts during these blooms, turning the water a reddish hue. Produces deadly toxin that can be passed to humans from fish/shell fish that consume them causing illness/death. Produces deadly toxin that can be passed to humans from fish/shell fish that consume them causing illness/death. After encountering and absorbing a red tide..a stingray becomes disoriented. They have the appearance of not being able to see or control what they are doing. Eventually the ray will stay at the surface lying horizontally and die.

Protists & Disease Parasitic & pathogenic Protists Parasitic & pathogenic Protists –malaria –Giardia –trypanosomes Plasmodium Giardia Trypanosoma

Any Questions??