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