Kingdom Protists Domain Eukarya Domain Bacteria Domain Archaea
Kingdom: Protists Domain Eukarya Domain Bacteria Domain Archaea Common ancestor Domain Eukarya
General characteristics • 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!
an ell sc mi s? eo u ae alg en gre red bro & d wn a iat lga om e s & c agel ilia late tes s ofl din ids no gle eu Great Diversity
Protist Diversity • 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: – flagellum – cilia – pseudopod
Kingdom Protista is REALLY Diverse: • We will divide & learn them in threegroups: – Animal-like – Plant-like – Fungus-like
Animal-like Protists • Aka Protozoans – heterotrophs, predators – Unicellular • Amoeba • Paramecium • Stentor Amoeba ingesting a Paramecium with food vacuoles stained red
Plant-like Protists • Plant-like Protists – autotrophs, photosynthesis – Unicellular or multi-cellular • Euglena • Algae (green, red, brown) • Diatoms • Dinoflagellates
Fungus-like Protists • Fungus-like Protists – Heterotrophs – Motile at some point in life cycle – Reproduce by forming spores • Water molds • Downy Mildews • Slime molds
Benefits of Protists • Plankton – phytoplankton • small algae + diatoms • much of the world’s photosynthesis • produces ~90% of atmospheric oxygen – zooplankton • heterotrophic protists + animals • key ecological role at base of marine food web Mmmmmm! Sounds like breakfast!
Benefits of Protists • Plankton – Food for humans • Kelp (brown algae or “sea weed”) • Used to thicken foods such as ice cream or jelly – Abrasives • Diatoms (silica shells *glass) • 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 • 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. 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. 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 – – – malaria Giardia Plasmodium trypanosomes Giardia Trypanosoma
Any Questions? ?
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