1. “The Junk Drawer” of Classification
KINGDOM PROTISTA
“The Junk Drawer” of Classification

2. Classified based on what they are NOT – they are NOT fungi, plants, or animals, but they are eukaryotes (in fact, they were probably the FIRST of the Eukarya)
Most are unicellular & microscopic
Groups (phyla) are based on physical characteristics (such as motility) and nutritional characteristics (heterotroph/autotroph)

3. First to reproduce sexually; first multicellular organisms
Live where ever there is moisture
Historically, divided into algae (plant-like) and protozoa (animal-like)

4. Rhizopods
Ex) Amoeba
Flexible surface, no cell wall, pseudopodia
Heterotrophs – engulf prey with pseudopodia; endocytosis/phagocytosis
nucleus
pseudopodia

5. Amoeba engulfing a paramecium with pseudopodia – An example of phagocytosis (a form of heterotrophy)

6. Heliozoans and Radiolarans
* Related to amoebas – pseudopodia & phagocytosis
Note the long, slender pseudopodia coming from the heliozoan on the left
Heliozoans are freshwater; radiolarans are marine
Both form the ooze on the floor of these bodies of water with the shells left from their dead bodies

7. Foraminiferans – another organism related to the amoebas; note the long pseudopodia coming out of the shell of calcium carbonate
- compose sedimentary rock
- both heterotrophic and photosynthetic (depending on the species)

8. Euglenoids/flagellates
Example – Euglena
Called flagellates because of their mode of motility
Have an eyespot for phototaxis
Have a contractile vacuole for water balance
Autotrophic/photosynthetic (look at the chloroplasts!) AND heterotrophic

9. Trypanosoma – genus of the protist that causes African sleeping sickness in humans (host) following the bite of the tsetse fly (vector)
Closely related to the euglenoids because they have similar body coverings.

10. Giardia – genus of another flagellated protist that causes disease in humans

11. Ciliophora - ciliates Example - Paramecium
All members of this group have cilia. Note there are even cilia lining the oral groove
*Have a contractile vacuole
*Have micro and macro nuclei
*Heterotrophic – food enters through oral groove, food vacuole forms, lysosomes help digest food
LOOK! Waste leaving cell via exocytosis

12. Another look at Ciliophorans: Stentor and Paramecium
FYI – Not in your notes
Another look at Ciliophorans:
Stentor and Paramecium

13. Dinoflagellates
Planktonic, photosynthetic protists – called phytoplankton (phyto = plant) AND heterotrophic species as well
Responsible for red tide (named for the photosynthetic pigment they contain); “blooms” of these organisms cause massive fish deaths due to the toxins they produce
Heterotrophic species use the toxins to stun prey (like fish) and then feed on its body fluids

14. Shells made of silica house the photosynthetic organism inside
Diatoms
Another group of protists (actually related to water molds and golden & brown algaes)
Shells made of silica house the photosynthetic organism inside
The shells are in two parts, fitting together like a shoe box or Petri dish

15. The Algae
Algae – collective term referring to all of the photosynthetic, plant-like protists; alga – singular; algal – adjective
Multicellular
Photosynthetic – the algae along with other photosynthetic protists are the largest group of producers on Earth, producing 1/3 of the oxygen
Algae rocks.
Chuck knows.

16. Algae
Have a variety of pigments, on which the name of each group is based (remember, -phyta means “plant”)
Golden algae – Chrysophyta; related to diatoms
Brown algae – Phaeophyta; “seaweed”; also closely related to the diatoms; kelp
Red algae – Rhodophyta; includes some “seaweeds” but not all. Form a separate group from the golden & browns algaes and the green algae; some species are heterotrophic
Green algae – Chlorophyta; “seaweeds”; have chlorophyll similar to plants; gave rise to the plant kingdom
Volvox (microscopic)

17. Water Mold
Oomycota – heterotrophic protist commonly found in very wet environments growing on dead or decaying organisms, such as on the fish below; called “mycota” because they look like fungi (but they’re NOT)
- late blight, a water mold, was responsible for the Irish potato famine

18. Slime Molds
Protists that aggregate in times of stress to form spore-producing bodies
Heterotrophic
Look like fungi but are NOT

19. Diseases caused include:
Sporozoans
Protists that are:
Nonmotile *Unicellular
Parasitic *Spore-forming
Disease-causing *Heterotrophic
Diseases caused include:
Malaria (host – vertebrates; vector - mosquito)
Toxoplasmosis (host – humans & cats)
cattle tick fever (host – cattle, mice, humans, deer, dogs)
Cryptosporidiosis (host – cattle humans, birds, deer, dogs, cats)
Malaria sporozoans of genus Plasmodium