By: Christian, Tony, and Sean

Introduction

• Simple Eukaryotic organisms • Study started in 1675 • Most are unicellular • Most live in oceans or fresh water • Many different kinds, with many different traits • Many serve as a major food source for other organisms

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Structure of Protists

Eukaryotic Uni-cellular (Multi-cellular in some stages) Some have Flagella (Comes out of reservoir) Some have Cilia Membrane bound organelles Nucleus Eyespot Some have chloroplasts for photosynthesis Cell membrane Some have a cell wall Food vacuole Endoplasm Cytoplasm Oral groove Anal pore

• • • Feeding Some are autotrophic Some are heterotrophic Structures for making and eating food Vorticella attaches itself to plants and algae and sweeps food into its mouth-like opening at the top of the bell with hair-like structures called cilia (shown in yellow). It eats bacteria and small protozoans.

This amoeba is busy capturing a ciliate by surrounding it with its pseudopodia. The nucleus can be seen just below the pseudopodia. Bottom left is a water expelling vesicle.

This suctorian ciliate is feeding on protozoan.

Reproduction Mitosis

• Parent cell divides • Turns into two cells • Each resulting cell is ½ size of parent cell • Occurs in protists such as Amoebas

Meiosis

• Occurs in protists such as Paramecia •Two cells join at oral grooves • Genetic material is transferred • Several divisions occur, resulting in eight new cells

Euglenophyta (Euglenoids) Chrysophyta (Golden Algae) Pyrrophyta (Fire Algae) Myxomycota (Slime Molds) Sarcodina (Sacrcodines) Cilliata (Cilliates) Sporozoa (Sporozans) Mastigophora (Flagellates) Euglenas Diatoms Dino Flagellates Slime Molds Amoebas Paramecia Plasmodium Trypanosomes

Trypanosoma Plasmodium in RBC (malaria) Red algae (Rhodophyda) Dinoflagellate Trichonypha Amoeba

Images

Euglena Viridis Tetrahymena Entamoeba Hystolictica (causes Dysentery)

More Images

Summary

• • • • • • • • • Eukaryotic and unicellular Complex Different types Reproduce by both meiosis and mitosis Are both asexual and sexual Some are heterotrophic Some are autotrophic Move with flagella or ciliae Some are parasites Unidentified ciliate protists attacking a juvenile Lampsilis. One of the uni-cells (arrow) is forcing its way between the partly open valves of the mussel. These protists can also invade the marsupia and feed on glochidia. However, it is not yet clear whether they attack healthy juveniles or merely act as scavengers on dead or dying individuals.

Additional Notes •Autotrophic protists contain chloroplasts and carry out photosynthesis.

•Protists are grouped as Algal-like, Fungal-like, or Animal-like (protozoans)