The weird, Wacky, wonderful
world of… Kingdom Protista!
Animal-like Animal-like ProtistsPlant-likePlant-like Protists
Fungus-likeFungus-like Protists
What is a protist??
• Kingdom Protista is a dumping ground for organisms that don’t fit into any other Eukarya kingdoms
– Eukaryotes
– Unicellular or colonial
– Lots of different life styles
– Live in most environments
– Categorized by nutrition
Autotrophic Protists
• Algae (singular: alga)• Photosynthetic
– Produce most of the oxygen in the atmosphere!
• No roots, stems, or leaves• 4 phyla:
– Euglenaphytes (no cell wall; can be heterotroph in low light)– Diatoms (patterned silica shells)– Dinoflagellates (cause of red tides and bioluminescence; some
are heterotrophs)– Red, Brown, Green algae
• Green algae were likely ancestral plants
Euglena
Dinoflagellates
Diatoms
Volvox
Chlamydomonas
Pediastrum
Volvox
A close-up of Volvox cells within the colony; 2 flagella and red eyespot are visible
Diatom cell wall is made of silica (like glass)
Bioluminescent Dinoflagellates
Red tides caused by toxic dinoflagellates. This red tide killed some fish.
Giant kelp are multicellular brown algae!
Fungus-like Heterotrophic Protists
• Saprotrophs (feed on dead organisms or live as plant parasites)
• Unlike fungi, they can move!
• 3 phyla: – Cellular Slime
Molds
– Plasmodium Slime Molds
– Water Molds
Dog Vomit Slime Mold
Slime molds creep by amoeboid movement – can move as much as 2.5 cm/hour!
Water mold growing on a dead mayfly larvae
Animal-like Heterotrophic Protists
• Proto = first; zoa = animals (singular: Protozoan, plural: protozoa)
• Unicellular• Heterotrophs• 4 phyla (mostly grouped based on method of
movement)– Ciliates– Flagellates– Amoeboids– Sporozoans
Ciliates & Flagellates
• Ciliates– Use cilia for movement
– Not parasitic
– Example: Paramecium
• Flagellates– Use flagella for movement
– Some parasitic, e.g.,…
• Trypanosoma (African sleeping sickness)
• Giardia lamblia
– Some mutualistic, e.g.,…
• Trichonympha (help termites digest wood)
Giardia lamblia
ParameciumTrichonympha
Cilia
Trichomonas vaginalis: an STD
African Sleeping Sickness (Trypanosoma)
Amoeboids• Move via pseudopod ("false foot")
– Pseudopods: Cytoplasm-filled projections
• Engulfs food by flowing around it
• Examples– Entamueba histolytica (amoebic
dysentery)
– Foraminifera (CaCO3 shell)
– Amoeba
Entamueba histolytica
Foraminifera Foraminifera Amoeba
Sporozoans
• Sporozoans– Parasitic; live inside a host
– Cannot move on their own
– Examples: Plasmodium falciparum (malaria), Toxoplasma gondii (toxoplasmosis)
Plasmodium Toxoplasma
Malaria in red blood cells