PROTISTS Objectives The Protozoa The Protozoa Small creatures, living out your busy lives, you know not what you teach me.

1. List the characteristics of the kingdom Protista: Protists are: -Unicellular -Eukaryotic

2. Discuss the four phyla of animal-like Protists, including characteristics and examples of each group: I. “CILIATES”(phylum Ciliophora) example: Paramecium -they have cilia -most are free living (not parasitic) -some have two nuclei -reproduce by binary fission, sometimes by conjugation

Objective 2, continued... II. “FLAGELLATES” or “ZOOFLAGELLATES” (phylum Zoomastigina) -they have flagella -absorb their food -many are parasitic Giardia lamblia

Objective 2, continued... III. “SPOROZOANS”(phylum Sporozoa) -reproduce by means of spores -non-motile -parasites -complex life cycles Cryptosporidium parvum

Objective 2, continued... IV. “SARCODINANS”(phylum Sarcodina) example: amoeba -use foot-like projections of their cytoplasm called pseudopods (“false-foot”) to move and feed -amoebas are flexible, active cells without cell walls, flagella, cilia, or even a definite shape -reproduce by binary fission

3. Discuss the role of animal-like Protists in the world: Many can be harmful: -Plasmodium, a Sporozoan, causes Malaria -Trypanosomes, which are flagellates, live in the blood of vertebrates and cause diseases like African Sleeping Sickness -Entamoeba, an amoeba, is a parasitic pathogen which causes amebic dysentery (yuck!) Others can be helpful: -Trichonympha, a flagellate, lives in the digestive tract of the termite, producing an enzyme which allows the termite to digest wood -Large numbers of Protists living in the oceans provide a starting point for the food chain

4. Discuss the five phyla of plantlike Protists in the World: I. “Phytoflagellates”(phylum Sarcodina) example: Euglena -Chloroplasts & flagella -Reproduce by binary fission -Without sunlight, they can also be heterotrophs -Euglena has a red “eyespot” to locate sunlight

4. Plantlike Protists, continued... II. “Dinoflagellates” (phylum Pyrrophyta, “fire-plants”) -Most photosynthesize & swim with flagella -Important phytoplankton (primary producers) -Many surrounded by thick plates of “armor” -Reproduce by binary fission -Many species are luminescent!

III. “Golden Protists”(phylum Chrysophyta) examples: yellow-green algae, golden brown algae, diatoms -Contain 1 or 2 gold/green chloroplasts -Cell walls made of pectin -Reproduce sexually or asexually -Diatoms live within cell walls of glass (silica) 4. Plantlike Protists, continued...

IV. “Slime Molds” (phyla Acrasiomycota and Myxomycota) -Found near rich sources of food such as rotting wood or piles of compost -Begin their lives as individual, amoeba-like cells -Cells team up to form a multi-cellular or a multi-nucleated blob -Reproduce by producing “fruiting bodies” which send out spores, which then give rise to more amoeboid cells...

5. Discuss the importance of plant-like Protists in the world: THEY MAY BE HARMFUL: -Euglenoids may form sewage “blooms” -”Red Tide”, which is a bloom of certain species of Dinoflagellate, can accumulate to toxic levels in shellfish THEY MAY BE HELPFUL: -Some corals and giant clams house the photosynthetic Dinoflagellates and use their energy -Plant-like Protists make up a major part of PHYTOPLANKTON, which is responsible for up to 70% of the photosynthesis taking place on Earth (food & Oxygen)