Protists Kingdom Protista

Overview of the history of life 4.5 BYA – Earth formed 4.5 BYA – Earth formed 3.5 BYA – Prokaryotes were abundant 3.5 BYA – Prokaryotes were abundant 3.0 BYA – Eubacteria and Archaea split 3.0 BYA – Eubacteria and Archaea split 2.5 BYA – oxygen revolution with lots of cyanobacteria 2.5 BYA – oxygen revolution with lots of cyanobacteria BYA – eukaryotes evolve, these are protists BYA – eukaryotes evolve, these are protists 1 BYA – protists colonize to form multicellular organisms (seaweeds) 1 BYA – protists colonize to form multicellular organisms (seaweeds)

Protozoans Animal-like protists Animal-like protists Have movement Have movement Heterotrophs Heterotrophs Unicellular Unicellular 3 kinds – Sarcodinians, zooflagellates, ciliaphorans 3 kinds – Sarcodinians, zooflagellates, ciliaphorans

Protozoan

Sarcodinians Sarcodinians – move by using pseudopods Sarcodinians – move by using pseudopods Pseudopods – lobes of cytoplasm used to move. Pseudopods – lobes of cytoplasm used to move. Live in fresh and ocean water Live in fresh and ocean water Ex. Amoeba (dysentery) Ex. Amoeba (dysentery) Some have hard shells – forams (foraminifera) – leave chalk deposits on cliffs around the sea Some have hard shells – forams (foraminifera) – leave chalk deposits on cliffs around the sea

Amoeba

Zooflagellates Zooflagellates – Move by means of flagella Zooflagellates – Move by means of flagella live in fresh water and ocean live in fresh water and ocean Ex. Euglena, Giardia (diarrhea), trichonympha (termites), trypanosoma (African sleeping sickness) Ex. Euglena, Giardia (diarrhea), trichonympha (termites), trypanosoma (African sleeping sickness)

Euglena

Giardia

Trichonympha

Trypanosoma

Ciliaphorans Ciliates – protozoans that move with short hair-like projections called cilia. Ciliates – protozoans that move with short hair-like projections called cilia. Ex. Paramecium – freshwater ciliate covered with a tough pellicle. Ex. Paramecium – freshwater ciliate covered with a tough pellicle. It holds food with food vacuoles It holds food with food vacuoles Paramecium uses an anal pore to eject waste and a contractile vacuole to release water. Paramecium uses an anal pore to eject waste and a contractile vacuole to release water.

Paramecium

Paramecium reproducing

Sporozoans Spore-forming protozoans Spore-forming protozoans Covered by thick, sporelike walls Covered by thick, sporelike walls Plasmodium – causes malaria Plasmodium – causes malaria

Plasmodium

Habitat Part of plankton in fresh and ocean water Part of plankton in fresh and ocean water Wet soil and leaf litter Wet soil and leaf litter Important in the food chain, feed on bacteria, yeast, algae Important in the food chain, feed on bacteria, yeast, algae Can be scavengers (decomposers) and parasites Can be scavengers (decomposers) and parasites

Algae Algae – plant-like protists that perform photosynthesis Algae – plant-like protists that perform photosynthesis Some are multicellular, some are unicellular Some are multicellular, some are unicellular Algae are important because they provide food for other organisms and they provide oxygen through photosynthesis. Algae are important because they provide food for other organisms and they provide oxygen through photosynthesis.

Unicellular Algae Dinoflagellates - protists with two flagella that propel them through the water like a top. Mostly salt water Mostly salt water Live symbiotically with jellyfish and coral Live symbiotically with jellyfish and coral Diatoms – protists with silica cell walls that lack flagella Very beautiful, important in making diatomaceous earth for cleaners, abrasives, toothpaste, asphalt Very beautiful, important in making diatomaceous earth for cleaners, abrasives, toothpaste, asphalt

Diatom

Dinoflagellate

Diatom

Multicellular Algae Green Algae Chlorophyta Chlorophyta Live mostly in fresh water and soil, some in ocean Live mostly in fresh water and soil, some in ocean Ex. Volvox, Ulva Ex. Volvox, Ulva Red Algae Rhodophyta Rhodophyta Live mostly in warm saltwater Live mostly in warm saltwater Have other pigments that trap sunlight Have other pigments that trap sunlight Brown Algae Phaeophyta Phaeophyta Cool saltwater Cool saltwater Kelps Kelps Reproduce by alternation of generations Reproduce by alternation of generations

Volvox

Red Algae

Kelp Forest

Alternation of Generations

Importance of Algae Phytoplankton – perform photosynthesis Phytoplankton – perform photosynthesis An important food source for many marine organisms An important food source for many marine organisms

Funguslike protists Important decomposers Important decomposers Plasmodial Slime Molds – form a mass of cytoplasm called a plasmodium Live around rocks and logs Live around rocks and logs Can become dormant when conditions are unfavorable Can become dormant when conditions are unfavorable Sexual reproduction Sexual reproduction Cellular Slime molds – live in fresh water and wet soil Water Molds – mildews and shower mold

Plasmodial Slime Mold

Cellular Slime Mold