LABORATORIO: PROTOZOANS Animal-like organisms

1. LABORATORIO: PROTOZOANSAnimal-like organisms

2. Goals for today • Learn to use the microscope • Learn to recognized the various protozoan phyla. • Learn their main ‘diagnostic’ characteristics • Learn about their biology and their ecological, economic, and medical importance

3. PROTOZOA Protozoa is a polyphyletic assemblage of animal-like organisms. This mean that many organisms grouped under Protozoa actually evolved independently, from different ancestors. Hickmann et al. 2011

4. PROTOZOA: What they share • Protozoan organisms have two animal like characteristics: • Absence of a cell wall • Presence of at least one motile stage in the life cycle

5. PROTOZOA: What they don’t have • They don’t have organs or tissues BUT have division of labor within the cytoplasm • Various organelles within the cytoplasm function as skeletons, locomotory systems, sensory systems, conduction, defense, etc.

6. PROTOZOA: Where can you find them? • Protozoan organisms are found in a variety of habitats: • Free living • Fresh, marine, and brackish water • Moist soils • Parasites • Symbiotic relationships

7. PROTOZOA: why are they important? • Although protozoa are frequently overlooked, they are ecologically very important: • As predators of algae, bacteria, and microfungi, • Herbivores • Decomposers • Parasites of great medical and economical importance

8. PROTOZOA: From chaos to ~order • Previously they belonged to the Phylum Protozoa where four main groups were recognized: • Flagellates • Amebas • Spore-formers • Ciliates • A new classification approach that considers PHYLOGENETICS and uses MOLECULES to construct their relationships recognizes 14 PHYLA !!!

9. PROTOZOA: Your Tasks • Phylum: Amoebozoa (naked amebas) • Species: Amoeba proteus

10. PROTOZOA: Amoeba proteus • Take a slide from your assigned box • Look at the Ameba and try to identify the nucleus and pseudopodia, contractile and food vacuoles. • We don’t have any parasitic Ameba but learn about this species: Entomoebagingivalis, where do you think it lives?

11. PROTOZOA: Amebas Amebas can be naked or enclosed in shells: • Amoeba proteusis a naked ameba that lives in freshwater. • Usually found in the underside of water plants. • Feed on algae, bacteria, protozoans, rotifers, and other microorganisms. • They are granulated in appearance

12. PROTOZOA: Amebas Amebas body: • The outer cell membrane= plasmalemma • The plasmalemma encloses the cytoplasm: ectoplasm & endoplasm. Amebas Feeding habits: • Phagocytosis: engulfing the food • Note the food vacuoles. • Lysosomes help digestion

13. PROTOZOA: Amebas Amebas locomotion: • Amebas move and change body shape by thrusting out pseudopodia. • Pseudopodia are extensions of the cell body. http://www.youtube.com/watch?v=7pR7TNzJ_pA

14. PROTOZOA: Amebas Amebas excretion: • Any undigested product is eliminated at any point of along the plasmalemma. Amebas osmoregulation: • Contractile vacuole: increases in size and then ruptures to the outside. • This organelle rids the ameba of the excess water taken from food or osmosis. Amebas nucleus: • Nucleus is disc shaped and finely granulated.

15. PROTOZOA: Amebas Amebas reproduction: • Asexually by binary fission Animation: http://www.classzone.com/books/hs/ca/sc/bio_07/animated_biology/bio_ch05_0149_ab_fission.html

16. PROTOZOA: Your Tasks • Phylum: Foraminifera • Marine shelled amebas • Secrete a skeleton of 1 or more chambers • Skeleton: Calcareous or silica, sand or sponge spicules • Long delicate pseudopodia • When died are fall to the bottom of the ocean forming enormous limestone deposits

17. PROTOZOA: Your Tasks • Phylum: Radiolaria • Marine shelled amebas • Secrete a transparent skeleton of silica • Slender pseudopodia come through the shell by pores

18. PROTOZOA: Your Tasks • Phylum: Euglenozoa • Species: Euglena gracilis (or viridis)

19. PROTOZOA: Euglena Euglena body: • Euglena gracilis is greenish because of chloroplasts that contain chlorophyll. • Body is covered by a pellicle secreted by the ectoplasm • The stigma or ‘eyespot’ is a reddish pigment that is light sensitive Euglena habitat • Common in still pools and ponds Euglena locomotion • Whiplike flagellum that maybe you can see with reduced light

20. PROTOZOA: Euglena Euglena osmorregulation: • Contractile vacuole eliminates excess of water and waste Euglena Feeding: • Photosynthetic • Carbohydrates are stored as starch granules and paramylon (carbohydrate similar to starch) Euglena Reproduction • Longitudinal fission when is free or encysted

21. PROTOZOA: Your Task • Phylum: Euglenozoa • Species: Trypanosoma

22. PROTOZOA: Trypanosoma • Your instructor will try to find Trypanosoma.So be patient. • What diseases are related to this protozoan? • Do report on Trypanosoma INSERT VIDEO: MONSTER INSIDE OF ME: Death by Tsetse Fly http://www.youtube.com/watch?v=4aVUrGO97Zg

23. PROTOZOA: Trypanosoma Trypanosoma : • Parasite that lives in blood or tissues of vertebrates. • Some species are not parasites Trypanosoma Feeding: • Osmotrophic= absorbs nutrients directly from surrounding blood or body fluids Trypanosoma diseases • Sleeping sickness (T. brucei gambiense, T.b. rhodesiense, T. b. brucei). • Chagas disease (T. cruzei). Darwin was believed to have had Chagas disease in his trip to Chile. Africa: Tsetse Central and South America “kissing bug”

24. PROTOZOA: Your Tasks • Phylum: Apicomplexa • Species: Plasmodium

25. PROTOZOA: Plasmodium • Your instructor will try to find Plasmodium in the slide. So be patient. • What diseases are related to this protozoan? INSERT VIDEO: Monsters Inside Me: Malaria http://www.youtube.com/watch?v=JwsoK8O0lXE

26. PROTOZOA: Plasmodium Plasmodium: • Causes malaria • 300 million people gets malaria every year. • 3 million people die every year. • Two hosts: • Anopheles mosquito (female) • Human

27. PROTOZOA: Your Tasks • Phylum: Ciliophora • Species: Paramecium

28. PROTOZOA: Paramecium Paramecium: • Ciliado that inhabits fresh water environments. Paramecium movement: • Very active and fast! • Movement by ciliary action Paramecium Body : • Mouth=cystostome • Body cover by a pellicle • Two nucleus: macro & micro nucleus

29. PROTOZOA: Paramecium Parameciumosmorregulation: • Contractile vacuole. • Located at the end of the body Paramecium nucleus: • Macronucleus: regulates metabolism of the cell • Micronucleus: contains the animal genome and is in charge of reproduction. Paramecium Trychocysts: • Is a structure under the pellicle that when explodes releases a liquid that hardens in water. • Believed to have a protective function. • When a paramecium feels threatened, trychocysts shoot out from the cell membrane like miniature arrows Discharged trychocysts

30. PROTOZOA: Paramecium Paramecium feeding: • Holozoic= feed on particucles e.g., bacteria • The anal pore (cytoproct) is located between the mouth and the posterior end of the body. • The anal pore is temporary only when food is discharged.

31. PROTOZOA: Paramecium Paramecium reproduction: • Conjugation • Binary fission Conjugation: oral grooves are attached

32. PROTOZOA: Your Tasks • Phylum: Ciliophora • Species: Vorticella

33. PROTOZOA: Vorticella • Solitary • Sessile ciliates • Ponds and streams • Stalk= is long ‘threat-like’ structure that attach it to the substrate. • Body is bell shape • Peristoma contains the oral disc. • Macronucleus is U shape • Reproduction is by binaary fission and budding

34. Important Links http://www.savalli.us/BIO385/Diversity/01.Protozoa.html http://www.microscopyu.com/moviegallery/pondscum/index.html http://www.mcwdn.org/Animals/PROTOZOA.html