‘The Protists’

Characteristics of Protists Animal-like Plant-like = algae/phytoplankton - Responsible for most of O2 released into atmosphere. Oxygen is a metabolic waste that is recycled for cellular respiration. Parasites Decomposers

Characteristics of Protists All are eukaryotic (has a nucleus) with membrane-bound organelles What is this cell? How can you tell? Prokaryote! ---NO Nucleus

Where did Protists come from? The eukaryotes evolved from the symbiosis of several cells Mitochondria and chloroplasts may be descended from small aerobic and photosynthetic prokaryotes The prokaryotes began to live inside larger cells Endosymbiotic Theory : Lynn Margulis

Endosymbiotic Theory

Animal-like Protists = “Protozoans” Classified by how they move Phylum Sarcodina Moves by pseudopods-temporary projections of cytoplasm (false feet) Reproduce by binary fission Ex: Amoeba & Entamoeba ‘the revenge’

Protozoans Phylum Zooflagellates (Zoomastigina) Have flagella - whip-like structures that aid movement Ex: Trichonympha - lives in gut of a termite, digests wood Ex. Trypanosomas - African sleeping sickness from bite of Tsetse fly Ex. Giardia - causes humans to become sick when drinking water with cyst

Protozoans Phylum Ciliaphora - ciliates Cilia - short, hair-like projections used for movement Most free living Ex: Paramecium

Protozoans Phylum Sporozoans - parasitic protists Nonmotile - do not move Ex: Plasmodium - causes malaria, carried by Anopheles mosquito

Plant-like Protists = “Algae” Unicellular & Autotrophic (Look At Article!) Phylum Pyrrophyta - Dinoflagellates Luminescent - give off blue light Causes ‘red tides’ = produces a nerve toxin that kills fish Gonyaulax - in shellfish & produces toxins that paralyze and kill humans and fish

Phylum Euglenophyta - flagellates with chloroplast Unicellular Algae Phylum Euglenophyta - flagellates with chloroplast Has 2 flagella and 1 eyespot Ex: Euglena - both autotrophic & heterotrophic

Unicellular Algae (Fill-In On Notes) Phylum Bacillariophyta - Diatoms Has glass-like cell walls made of silica Forms diatamaceous soil used to filter and as an abrasive (toothpaste). Shaped like 2 sides of a pillbox/culture dish

Unicellular Algae - (Fill-In On Notes) Phylum Chrysophyta: yellow-green and golden-brown algae

Phylum Chlorophyta - Green Algae Multicellular Algae Similar to plants. Both have…. cell walls photosynthetic pigments multicellarity Fill in on notes Phylum Chlorophyta - Green Algae Ex: Volvox are colonial

Phylum Rhodophyta - Red Algae Multicellular Algae Phylum Rhodophyta - Red Algae Used to make agar Phylum Phaeophyta - Brown Algae Ex: Kelp and Sargassum

Unusual Protists – “Decomposers” Slime molds

Unusual Protists - Decomposers Water molds Grow in water or damp places on land Ex: mildews, white rusts, water molds & Saprolegnia (ick on fish) Ex. Phytopthora infestans (Potato blight) -threatened crops in Ireland “The Great Potato Famine”