Protozoans

1. Protozoans

2. Protozoan Groups Apicomplexans Sarcodines Ciliates Flagellates

3. Colonial Flagellates Volvox colony

4. Protozoan Taxonomy Morphological taxonomy Phylum sarcomastigophora Subphylum mastigophora Flagellates Phytoflagellates Zooflagellates Subphylum sarcodinia Amoebas Foramiferans Radiolarians Phylum Ciliophora Ciliates Phylum Apicomplexa parasitic protozoa Spore forming protozoans Molecular taxonomy Indicate that morphological relationships are tenuous Divergence between phyla of protozoa as great as between kingdoms (i.e. animalia, fungi and plantae) Revisions are continuously occurring

5. Basis of Taxonomy Morphological traits Flagella Cilia Pseudopodia Shells (tests) Reproductive modes Sexual Asexual Spore formation Distinct reproductive cell forms Cyst formation Characteristic organelles Apical complex Kinetoplast Presence/Absence of mitochondria Trophism Heterotrophic Autotrophic

6. Flagella & Cilia

7. Fig. 5.5, pg 89

8. Pseudopodial Movement

9. Amoeba • Amoeboid movement • Pseudopodial extension • Phagocytosis • Engulfment of large particles

10. Contractile Vacuoles • Osmotic regulation • Remove excess metabolic H2O, and HCO3 • Remove H2O that enters by osmosis • Refer to fig 5.7

11. Feeding Fig 5.6, page 90

12. Examples of Binary Fission – Asexual Reproduction Fig 5.8, page 91

13. Radiolarian Undergoing Binary Fission

14. Sexual Reproduction • Conjugation • Meiotic nuclear division • Transfer of portion of genome between partners • Sporogomy • Formation of sporozoites • Formation of gametocytes from sporozoites • Fusion of gametocytes to form new generation of sporozoite • Gametocytes and sporozoites are present in separate hosts

15. Cell Specialization in the Colonial Volvacae Fig 5.11, page 93

16. Reproduction in Ciliates – Sexual and Asexual Conjugation Fission Fig 5.18, pg 98 Fig 5.9, page 91

17. Conjugation

18. Conjugation

19. Conjugation

20. Cyst Formation Fig 5.1, page 85

21. Taxonomy of Kingdom Protozoan

22. Phylogenic Distinctions Kingdom Animalia Kingdom Protista Protozoans

23. Phyla Retortamonada and Axostylata • Derived from an early ancestral eukaryote • Retortamonada • Lack both mitochondria and Golgi bodies. • Include Giardia lambia – intestinal parasite, produces violent, but not fatal symptoms. • Produces cyst that are passed by the host, host is infected by contaminated drinking water. • Axostylata • Have a stiffening rod, the axostyle, composed of microtubules that extend along the longitudinal axis. • Members of the Order Trichomonadida contain hydrogenosomes, that function in the same method as mitochondria . • Tichomonas vaginalis – sexually transmitted parasitic, causes urinary tract infections.

24. Phyla Retortamonada and Axostylata Giardia lambia Tichomonas vaginalis

25. Phylum Chlorophyta • Plant-like Protozoan's • Autotrophic, and contain one or more chloroplast (organelles that contain the pigment chlorophyll used for photosynthesis) • Single celled algae such as Chlamydomonas • Colonial organisms such as Gonium and Volvox

26. Phylum Euglenozoa • A phytoflagellate • Autotrophic • Opportunistic heterotroph • Contain a light sensitive organelle known as the Stigma. • Kinetoplast, large disk of DNA contained in the mitochondria • Major cause of parasitic infections throughout the world. • Genus Trypanosoma • Genus Leishmania

27. Trypanosomiasis • African sleeping sickness – Eastern hemisphere • Trypanosoma brucei • Vector – Tsetse Fly - Glossina spp Immages from links at http://www.biosci.ohio-state.edu/~parasite

28. Trypanosomiasis • Chaga’s disease – Western hemisphere • Trypanosoma cruzi • Vector – assassin bug – Rhodnius spp, Panstrongylus spp and Triatoma spp

29. Life Cycle of Trypanosoma

30. Trypanosoma • Early diagnosis – treatment very successful • Suramine or Pentamidine depending on subspecies of trypanosome • Late phase treatments • Low success rate • Serious side effects (including lethality) of drugs • Melarsoprol – often causes sever allergic reaction which causes neural damage • Eflornithine – only effective against gambiense subspecies and is no longer produced • These drugs contain arsenic

31. Leishmania • Leishmania donovani “referred to as Dum-Dum Fever or kala-azar” • Spread by sand flies; phlebotomus spp. • Common in Africa and India, and rare in the Mediterranean and Latin America. • Causes fever, malaise, progressive wasting, anemia, lesions, enlargement of the liver and spleen, facial scarring and death.

32. Leishmaniasis • Treatments – Antimony containing compounds • meglumine antimonate • sodium stibogluconate

33. Life Cycle of Leishmania

34. Phylum Apicomplexa • Parasitic • Reproduce both sexually and asexually • Set of organelles called the Apical Complex • Present in the sporozoite for invading the host cells • Cilia, flagella or pseudopodia – but these are lacking in most species. • Form spores • Two main Classes • Gregarinea – intestinal parasites, normally complete life cycle within one host. • Coccidea – vertebrate parasites include; • Cryptosporidium • Toxoplasma • Plasmodium – malaria • 500 million cases annually • 1-2 million deaths annually

35. Apical Organelles of the Apicomplexans Fig 5.13, page 95

36. Life Cycle of Plasmodium falciparum Fig 5.14, page 96

37. Phylum Ciliophora • Large, diverse phyla • Typically found in marine or freshwater environments • Range in size from 10um to 3mm long and all have cilia during their life cycle • Multinucleate • Macronucleus – controls metabolism, synthesis of organic molecules and development of the organism • Micronucleus – function in sexual reproduction and give rise to the macronucleus after sexual reproduction. • Holozoic, feeds on organisms via a cytostome • Defensive and predatory adaptations • Trichocysts – defensive • Toxocysts – toxic to paralyze prey • Pellicle – protective coating that can range from a single cell in thickness to a thick armored covering

38. Phylum Ciliophora– Parmecium sp Fig 5.17, page 98

39. Some other Ciliates Fig 5.15, pg 97

40. Phylum Dinoflagellata • Ecologically important • Primary producers in marine environments – photosynthetic varieties • Commonly have two flagella • Either photosynthetic or herbivores • Some species are bioluminescent • Zooxanthellae gen. live in mutualistic relationships with other protozoans, sea anemones, coral and clams (ex. with stony coral which produces coral reefs) • Some species are responsible for red tides • Release toxins that paralyze or kill fish • Protozoans then feed on fish • Can affect humans be affecting the respiratory and nervous systems, as well as causing sores to develop.

41. Dinoflagellates

42. Amebas • Fresh and salt water environments, and soil moisture • Planktonic or substratum • Holozoic • Some parasitic species • Entamoeba histolytica • Brain infections • Protective tests (or shells) form to protect the organisms • Formaninferans – include sand into the test • Radiolarians • Marine, planktonic with siliceous skeletons • Among the oldest known species of protozoans • Common throughout the geologic or fossil record

43. Examples of Amebas