1. Unit 2: Protozoans

2. General Characteristics Most are unicellular organisms (some are multi-cellular in a life cycle) Show evidence of intracellular specialization-> division of labor in the cell Mostly microscopic Reproduction: both asexual and sexual are represented

3. General Characteristics: Types of Relationships Free living Predator/Prey Symbiotic: close interaction between 2 organisms – Mutualism: both benefit – Commensalism: one benefits and one is not helped or harmed – Parasitism: one benefits and one is harmed

4. General Characteristics Most are mobile-> move by pseudopodia, cilia, flagella Location-> wherever life exists (aquatic or terrestrial habitats) Highly adaptable-> some organisms form cysts – Cysts: dormant forms of the organism covered by a resistant external shell. Can travel by air and water Many contain a contractile vacuole- functions in osmo-regulation; removal of excess water from the cytoplasm by osmosis

5. General Characteristics All types of modes of nutrition are observed – Autotrophic: organisms that can make their own food – Heterotrophic: organisms that obtain their food from an outside source – Saprozoic: ingests nutrients that are dissolved

6. Protozoans are similar to animals because: 1) Both are mobile 2)Both can ingest food 3) Neither have a cell wall

7. Protozoans exhibit intracellular organization They contain the following organelles: – Nucleus- Cell Membrane – Nucleolus- Cytoplasm (ecto and endo) – Mitochondria-Cilia and Flagella – ER – Golgi Apparatus – Chloroplasts (some) – Vacuole (contractile

8. Protozoan Groups There will be 8 different Protozoan groups we will discuss in this chapter. They will include: – Phylum Retortamonada- Phylum Ciliophora – Phylum Axostylata- Phylum Dinoflagellata – Phylum Chlorophyta- Amoebas – Phylum Euglenozoa – Phylum Apicomplexa

9. Phylum Retortamonada Lacks a mitochondria and a golgi Example: Giardia: Parasite of humans in their intestine Symptoms: diarrhea Transferred by: water contaminated with feces Can encase in a cyst to survive harsh conditions

10. Giardia

12. Phylum Axostylata Contain an axostyle: a rod composed of microtubules that run along the longitudinal axis of the body. Some classes contain a Parabasal body: very large golgi body Some orders contain Hydrogenosomes: analogous to mitochondria; can make hydrogen without oxygen.

13. Phylum Axostylata : Examples 1) Trichonomas vaginalis: Parasite of the male and female urogenital tract Sexually transmitted Causes vaginitis in females

14. Phylum Axostylata : Examples 2) Trichonympha: Mutualistic symbiont that lives in the gut of termites Function: aid in the digestion of cellulose Termites cannot break down cellulose in wood. Trichonympha breaks down the cellulose for the termite and the Trichonympha gets a place to live.

15. Phylum Chlorophyta Unique features: Plant-like protozoans Mode of nutrition: autotrophic- most have chloroplasts Can be unicellular or multicellular

16. Phylum Chlorophyta: Example Volvox globator – multi cellular; composed of thousands of flagellated cells that are embedded in a gelatinous matrix (looks like a green hollow sphere) – Contains chlorophyll – Mostly located in fresh water

17. Volvox

18. Chlorophyta- Volvox Shows a division of labor: – Anterior end of the organism contains somatic cells that function in nutrition and locomotion – Posterior end of the organism contains cells focused on reproduction

19. Chlorophyta- Volvox Each individual cell contains: – Nucleus – 2 flagella – 2 contractile vacuoles – Chloroplast – Eyespot

20. Chlorophyta- Volvox Reproduction – Asexually in the spring and summer – Sexually in the fall

21. Phylum Euglenozoa Some are autotrophic: contain chloroplasts with chlorophyll Some are phagotrophic and can engulf prey Has a light sensitive eyespot Has an anterior pocket with 2 flagella emerging Has a Pellicle: thin, translucent envelope covering the outside

22. Phylum Euglenozoa Contains 2 Sub-Phyla a) Euglenida b) Kinetoplasta

23. Phylum Euglenozoa a) Sub Phylum Euglenida Example: Euglena viridis – Contains a flexible pellicle – Has a contractile vacuole – No cell wall – Has paramylon granuoles for food storage – Located in fresh water/streams

24. Euglenida viridis Mode of Nutrition: autotrophic, phagotrophic, and saprozoic Movement: Euglenida movement-> squirming Adaptations: can form cysts to survive harsh environmental changes Reproduction: Binary Fission – No sexual reproduction

25. Euglena viridis

26. Phylum Euglenozoa b) Sub Phylum Kinetoplasta Nutrition: Parasitic and heterotrophic Contains a Kinetoplasta: cellular organelle that has extra nuclear DNA

27. Phylum Euglenozoa b) Sub Phylum Kinetoplasta 2 examples of the sub-phylum Kinetoplasta – Trypanosomas (genus) – Trapanosoma cruz

28. Trypanosoma Species of organisms that cause African Sleeping Sickness Transmit A.S.S. by the bite of a Tse tse fly Causes brain damage and leads to fatality

29. Trypanosoma- African Sleeping Sickness

30. Trypanosoma cruzi Causes: Chagas Disease Located in Central and South America Transmitted by the bite from Triatominae (kissing bug) Causes dysfunction of the central and peripheral nervous system-> death

31. Trypanosoma cruzi

32. Super Phylum Alveolata All members contain an alveoli: membrane bound sac that produces pellicles and thecal plates Super phylum members include: – Apicomplexa – Ciliophora – Dinoflagellates

33. Phylum Apicomplexa Unique Characteristics – Apical complex: combination of different organelles that allow the organism to penetrate their host – Forms a cyst/spore at some point in their lifecycle – Endoparasite: parasite that lives inside their host – Reproduction: both sexually and asexually

34. Phylum Apicomplexa Examples: – Toxoplasma gondii causes Toxoplasmosis – Plasmodium causes Malaria

35. Toxoplasma gondii Unique characteristics: – Can enclose in a cyst to survive harsh conditions – An example of zoonosis: a disease of “animals” that can infect humans – The parasite can produce “extra-intestinal” stages and begin to spread to other tissue

36. Toxoplasma gondii Parasitizes nearly all warm-blooded animals including pets (cats) and humans