1. Kingdom Protista

2. What is a Protist?
A Protist is any organism that is not a plant, animal, fungus, or prokaryote.
Very diverse kingdom
Single celled  Multicellular
Range in size from μm to 50m+
Plant like, animal like and fungus like!

3. Evolution of Protists
Protista comes from Greek words meaning “the very first”
First eukaryotes (1.5 billion years ago)
May have evolved through the endosymbiosis of prokaryotic cells

4. Classification of Protists
Grouped according to how they obtain nutrition.
3 main groups:
animal like
plant like
fungus like

5. Animal-like Protists Once called protozoa (first animals) Heterotrophs
unicellular
Grouped according to their method of movement.
4 Groups:
Zooflagellates
Sarcodines
Ciliates
Sporozoans

6. Zooflagellates Belong to phylum Zoomastigina Swim using flagella
Feed by absorbing
Live in lakes, streams, and bodies of other organisms
Examples: Trichonympha & Trypanosoma

7. Sarcodines Belong to phylum Sarcodina Live in water
Use pseudopods for movement and feeding
Example: Amoeba
move by streaming cytoplasm into pseudopods (amoeboid movement)

8. Other sarcodines:
Foraminiferans have shells made of CaCO3
Heliozoans (radiolarians) have shells made of SiO2

9. Ciliates Belong to phylum Ciliophora
Use cilia for movement and feeding
Most complex unicellular protists
Example : Paramecium

10. Special features of ciliates:
Trichocysts for defense
Macronucleus – working nucleus
Micronucleus – “back up copy” of genes
Become genetically different by conjugation

11. Sporozoans Belong to phylum Sporozoa No means of movement
All parasitic with complex life cycles involving more than one host
Example: Plasmodium (causes malaria)

13. Diseases caused by Animal-like Protists
African sleeping sickness
Dysentary
Malaria

14. Ecology of Animal-like Protists
Some live symbiotically within other organisms
Parasites
Decomposers
Part of food chain