Kingdom Protista Biology 11

Background: Protists first appeared in the fossil records about 1.5 billion years ago. Demonstrate an important evolutionary advancement, a membrane bound nucleus. Contain organelles such as ribsomes, mitochondria, and lysosomes.These structures provide a more efficient method of using available nutrients. Reproduce sexually and asexually. Require an aquatic environment.

Characteristics: Eukaryotes (have a nucleus and other organelles) Mostly unicellular (single cell) Some heterotrophs, some autotrophs

Protista is divided into 3 large groups: Based on the organisms they most resemble Animal-like Protists Plant-like Protists Fungus-like Protists

1. Animal-like Protists: 4 phyla (classified on the basis of their method of movement Rhizopods (Sarcodina): move by pseudopods (extensions of the cytoplasm) Ciliata (Ciliophora): move by cilia (tiny hair structures) Flagellata (Zoomastigina): move by flagella (whip like tail) Sporozoa: no movement

2. Plant like Protists: 6 phyla (mostly based on colour) Euglenoids (Euglenophyta) Green Algae (Chlorophyta) Golden Algae (Crysophyta) Red Algae (Rhodophyta) Brown Algae (Phaeophyta) Fire Algae (Phrrophyta)

3. Fungus like Protists: 3 phyla Includes slime molds, water molds, mildew

Pseudopods: http://www.youtube.com/watch?v=x1ErCyZCFw8