1. Protozoa

2. Characteristics Mostly unicellular, and free-living Found in soil and water More animal like than plant like Not photosynthetic

3. Characteristics A typical protozoan life cycle has 2 stages – a trophozoite and a cyst. The trophozoite is the motile, feeding, dividing stage. The cyst is the nonmotile, dormant, survival stage.

4. Characteristics Protozoa are divided into groups, based on their method of locomotion: – Amebae move by means of pseudopodia (“false feet”) Look for them in the video below! – Ciliates move by means of hairlike cilia – Flagellates move by means of whiplike. – Sporozoa have no visible means of locomotion Ameba Movement Ameba Movement Paramecium

5. Protozoa That Cause Human Diseases Plasmodium spp. – cause malaria, transmitted by Anopheles mosquito Enormous impact on human history

6. Sickle-cell hemoglobin Normal hemoglobin 1 23 4 5 6 7... 146 1 23 4 5 6 SEM Prevalence of sickle cell gene Historical distribution of malaria

7. Protozoa That Cause Human Diseases Trypanosoma brucei gambiense – causes African Sleeping Sickness... transmitted by Tsetse flies Trypanosoma cruzi – causes Chaga’s disease

8. Protozoa That Cause Human Diseases Trichomonas vaginalis – trichomoniasis (STD) Giardia lamblia – persistent diarrheal disease