1. Mic 101: L20 Protozoa : Ref-Tortora

2. The Protozoa Unicellular eukaryotes without cell wall Simple heterotrophic metabolic pattern Found in natural water Seen under the microscope

3. General Characteristics Eukaryotic, Unicellular, without cell wall Colourless and motile Non-pigmented, heterotrophic Divides by binary fission Ingest food by phagocytosis Contain different locomotive organs, eg. Cilia, flagella, pseudopod.

4. Giardia and Mircosporidia are the least evolved protists with no mitochondria and no other membraneous organelle except the nucleus. Method of energy production is by anaerobic hydrogenosome. Phylogenetically, Protozoa can be devided into Diplomonads, Microsporidia, Trichomonads, Trypanosomes, Flagellates, Euglenoids and slime molds.

5. Major Groups Depending on phenotypes: Mastigophora Euglenoids Sarcodina Ciliophora Apicomplexa

6. Mastigophora Contain more than one flagella. Found in fresh water and animal intestine. 20 μm in length Both flagella and cell membrane make the cell to move Flagella contain basal body and hook like prokaryotic cells but the protein in hook is of eukaryotic origins.

7. Euglenoids Phototrophic flagellate Found in both fresh and marine water Contains chlorophyll a and b Carbon storage is done in the form of paramylon.

8. Sarcodina Some members secrete a polymer which become like a hard cover outside vegetative cell Can form a resistant non-vegetative structure called cyst Movement by means of gliding and formation of pseudopods

9. Ciliophora Posess cilia at some stage of the life cycle Contain two kind of nuclei: micro-nuclei and macro- nuclei Micro-nucleus contains genomic DNA and take part in reproduction; macro-nucleus contains DNA and mRNA Ingest food by phagocytosis e.g. Paramecium

10. Apicomplexa Commonly called sporozoa Obligate intracellular parasite Metabolize together with other organism Form a resistant structure called sporozoite which only transmit the cell from one host to another. e.g. Plasmodium (malaria)

11. Relation to Disease Trypanosoma cruzii causes African sleeping sickness which is fatal Giardia lamblia causes severe fulminant dysentery Entamoeaba histolytica causes amoebic dysentery Plasmodium causes malaria Lieshmania donovanii causes kalazar

12. Control of Major Protozoal Pathogens Chlorination of drinking water Boiling or filtration of drinking water Microscopic examination of samples Ingestion of anti-protozoal drugs eg. Metronidazole, miltefosine, emetine, quinine Destruction of the alternate vector