The Eukaryotes

1. The Eukaryotes What makes a eukaryote? Why are these infestations/infections important?

2. Fungi • Algae • Protozoa • Helminths • Arthropods

3. Fungi • Mycology is the study of fungi. • Fungal infections are increasing • Are aerobic or facultatively anaerobic Chemoheterotrophs. • Decomposers that are parasites of plants.

4. Fungi Characteristics • Thallus consists of filaments called hyphae, a mass of hyphae is mycelium. • Yeasts are unicellular fungi. • Some yeast can change morphology are mold like at 25’C • Classified according to the sexual structure that is formed. • Grow in acidic, low moisture aerobic environments. • Can metabolize complex carbs.

5. Yeasts • Unicellular fungi • Fission yeasts divide symmetrically • Budding yeasts divide asymmetrically Figure 12.3

6. Dimorphism • Pathogenic dimorphic fungi are yeastlike at 37°C and moldlike at 25°C Figure 12.4

7. Molds • The fungal thallus consists of hyphae; a mass of hyphae is a mycelium. Figure 12.2

8. Vegetative Growth Figure 12.1

9. Asexual Reproduction • Conidia or conidiospores Figure 12.5a

10. Asexual Reproduction • Arthroconidia Figure 12.5b

11. Asexual Reproduction • Blastoconidia Figure 12.5c

12. Asexual Reproduction • Chlamydoconidia Figure 12.5d

13. Asexual Reproduction • Sporangiospores Figure 12.5e

14. Sexual Reproduction • Three phases: • Plasmogamy: Haploid donor cell nucleus (+) penetrates cytoplasm of recipient cell (–) • Karyogamy: + and – nuclei fuse • Meiosis: Diploid nucleus produces haploid nuclei (sexual spores)

15. Sexual Spores • Zygospore: Fusion of haploid cells produces one zygospore Figure 12.6

16. Sexual Spores • Ascospore: Formed in a sac (ascus). Figure 12.7

17. Sexual Spores • Basidiospore: Formed externally on a pedestal (basidium) Figure 12.8

18. Some Fungal Diseases • Systemic mycoses are infections within the body may affect many organ systems. • Subcutaneous under skin. • Cutaenous is in skin nails and hair ect. • Superficial mycoses on only exterior parts. • Opportunistic: aspergillosis caused by Aspergillus, Candidiasis Candida

21. Economic Effects of Fungi. • Many are used for production of food and beverages. • Biological control of pests. • Mold spoilage of fruits grains and vegetables. • Diseases in plants. • Infections in fuel lines fungal mats. • Degradation of cellulose materials.

22. Treatments of Fungal Infections • Amphotericin B destroys membrane used on Systemic fungal infections. • Griseofulvin (inhibit mitotic microtubules) on many skin fungi. • Tolnaftate (Athletes foot) • Can you think of any others?

23. Lichens • Mutualistic combination of alga and fungus. • One is photosynthetic, on is the holdfast absorber. • Colonize habitats that are unsuitable for either the alga or the fungus alone. • Used for pigments and air quality indicators.

25. Algae • Unicellular filamentous are Multicellular. • Most algae live in aquatic environments.

26. Characteristics • Eukaryotic photoautotrophs. • Thallus or body is stipe, holdfast and blades. • Reproduce sexually and asexually by fragmentation. • Most reproduce sexually. • Photoautrophs that produce oxygen. • Classified by structure and pigments.

28. Characterized by color • Brown algae (kelp) • Red algae grow at deeper levels. • Green algae similar to plants. • Diatoms unicellular produce neurotoxins. • Dinoflagellates also cause neurotoxins.

30. Role in Nature • Primary producers in aquatic food chains. • Produce most of molecular oxygen • Much of our petroleum is fossil remains of plankton. • Many unicellular algae are symbionts in animals.

32. Protozoa • Are unicellular eukaryotic Chemoheterotrophs. • Found in soil, water and as normal microbiota

33. Some that cause disease. • Archaezoa lack mitochondria and have flagella. Trichomonas and Giardia • Microsporidia lack mitochondria and microtubules cause diarrhea in AIDS patients • Rhizopodia are amoeba, include Entamoeba and Acanthamoeba

34. More Disease • Apicomplexa can penetrate host tissue include Plasmodium and Cryptosporidium • Ciliophora move by means of cilia Balantidium coli is a human parasitic ciliate • Euglenozoa move by means of flagella and lack sexual reproduction include Trypanosoma

35. Protozoa

36. Characteristics of Protozoa • Vegetative form is a trophozoite • Asexual reproduction is by fission, budding, or schizogony • Sexual reproduction by conjugation • Some produce cysts

37. Medically Important Phyla of Protozoa • Archaezoa • Microspora • Amoebozoa • Apicomplexa • Ciliophora • Euglenozoa

38. Archaezoa • No mitochondria • Multiple flagella • Giardia lamblia • Trichomonas vaginalis (no cyst stage) Figure 12.16b

39. Archaezoa Figure 12.16c, d

40. Microspora • No mitochondria • Nonmotile • Intracellular parasites • Nosema

41. Amoebozoa • Move by pseudopods • Entamoeba • Acanthamoeba Figure 12.17a

42. Apicomplexa • Nonmotile • Intracellular parasites • Complex life cycles • Plasmodium • Babesia • Cryptosporidium • Cyclospora

43. The Life Cycle of Plasmodium vivax 2 3 8 7 6 Figure 12.18

44. Cryptosporidium Clinical Focus, p. 355

45. Cryptosporidium Clinical Focus, p. 355

46. Ciliates • Move by cilia • Complex cells • Balantidium coli is the only human parasite Figure 12.19

47. Euglenozoa • Move by flagella • Euglenoids • Photoautotrophs Figure 12.20

48. Euglenozoa • Move by flagella • Hemoflagellates • Trypanosoma spp. • Sleeping sickness • Chagas’ disease Figure 23.22

49. Euglenozoa • Move by flagella • Photoautotrophs • Euglenoids • Chemoheterotrophs • Naegleria • Flagellated and amoeboid forms, meningoencephalitis • Trypanosoma • Undulating membrane, transmitted by vectors • Leishmania • Flagellated form in sand fly vector, ovoid form in vertebrate host

50. Slime Molds • Not obvious pathogens. • Cellular slime molds resemble amoebas and ingest bacteria by phagocytosis. • Plasmodial slime molds consist of multinucleated mass of protoplasm that engulfs organic debris and bacteria as it moves. • All can produce large fruiting bodies.