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?Endosymbiotic Theory : Lynn Margulis
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
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’
ProtozoansPhylum 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
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
(Look At Article!)
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
Multicellular Algae
Phylum Chlorophyta - Green Algae
Ex: Volvox are colonial
Similar to plants. Both have….• cell walls• photosynthetic pigments• multicellarity
Fill in on notes
Multicellular AlgaePhylum Rhodophyta -
Red AlgaeUsed to make agar
Phylum Phaeophyta - Brown Algae
Ex: Kelp and Sargassum