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Fungi and P rotists

Fungi and P rotists. Endosymbiotic Origin of Eukaryotes. Schimper in 1883 proposed that chloroplasts are cyanobacteria living inside plant cells . Andreas Franz Wilhelm Schimper (1856-1901, Germany). Endosymbiosis.

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Fungi and P rotists

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  1. Fungi and Protists

  2. Endosymbiotic Origin of Eukaryotes Schimper in 1883 proposed that chloroplasts are cyanobacteria living inside plant cells Andreas Franz Wilhelm Schimper(1856-1901, Germany)

  3. Endosymbiosis Figure from Margulis (1970); note the figure illustrates endosymbiosis and the origin of the 5 kingdoms. Proposed with explanation by Lynn Margulis (1938-2011, USA) in 1967 based on her work and drawing on the works of Konstantin Merezhkovsky (1855-1921, Russia) and Ivan Wallin (1883-1969, USA).

  4. Archaezoa Hypothesis • Autogenoustheory (Archezoa Hypothesis- Cavalier-Smith 1983) • Organelles evolved within the cell by progressive compartmentalization • HOWEVER, Roger (1999)- all extant eukaryotes have mitochondrial genes in their nuclear DNA • Later, Cavalier-Smith accepted endosymbiosis Thomas Cavalier-Smith (1942, Britain)

  5. Evidence that these organelles have prokaryotic traits: Mitochondria and chloroplasts • Circular DNA • Synthesize proteins • Divide by fission • Mutate SSU rDNA phylogeny

  6. a larger prokaryote (or perhaps early eukaryote) engulfed or surrounded a smaller prokaryote (permanent resident) some 1.5 billion to 700 million years ago

  7. Plasma membrane DNA Cytoplasm endomembrane system evolved from inward folds of the plasma membrane of a prokaryotic cell Ancestral prokaryote Endoplasmic reticulum Nuclear envelope Nucleus Cell with nucleus and endomembrane system

  8. Serial Endosymbiosis Theory Max F.J.R. Taylor (1939, South Africa and Canada); eukaryote created following endosymbiosis with mitochondrial bacterium. Further developed Margulis Endosymbiosis • Serial endosymbiotic theory (SET (1974-1990)) organelles are the result of successive engulfments…

  9. Photosynthetic prokaryote (Some cells) Chloroplast Mitochondrion • endosymbiosis generated mitochondria and chloroplasts -Proteobacteria Aerobic heterotrophic prokaryote Cyanobacteria Aerobic cells use oxygen to release energy from organic molecules by cellular respiration Photosynthetic eukaryotic cell

  10. Insights from recent results: • Reduce the number of secondary losses of mitochondrial • Group together many amitochondriate lineages • Find evidence of very reduced mitochondria • Mitochondrial monophyly? • (discoid, flattened, and tubular cristae) • Reduce the number of secondary endosymbioses (photosynthetic eukaryote being engulfed by another eukaryote) • Group together branches with chloroplast surrounded by four membranes • The initial endosymbiotic events were rare and most diversity through secondary endosymbioses

  11. Eukaryotic Domains Tree of Life generated by Sandra Baldauf of Uppsala University using multigene analyses

  12. Amoebozoa • Unicellular • Heterotrophic • Most are free-living, a few are important parasites

  13. Amoeba

  14. Physarum

  15. Eukaryotic Domains

  16. Excavates • Unicellular • Most are heterotrophs, commensals, a few are parasites • No sexual reproduction known • Mitochondria absent (lost them)

  17. Trichonympha

  18. Eukaryotic Domains

  19. Discicristates • Some photosynthetic (secondary endosymbiosis) • Some are free-living heterotrophs • Some are important parasites

  20. Euglena

  21. Trypanosoma

  22. Eukaryotic Domains

  23. Chromalveolates • Supergroup contains some of the most important organisms in the oceans • Range in form from simple single cells to complex multicellular taxa • Vary from heterotrophs to parasites to autotrophs • Includes 2 kingdoms: Heterokontae and Alveolatae

  24. Heterokontae • United by same type of motile cell • Very diverse

  25. Phaeophyta (the Brown Algae)

  26. Diatoms

  27. Alveolatae • All unicellular • Many with complex life histories • Free-living and symbionts • Photosynthetic, heterotrophic, commensals, parasitic • United by type of cell covering

  28. Alveolae

  29. Ciliata

  30. Apicomplexa

  31. Dinoflagellata

  32. Eukaryotic Domains

  33. Rhizaria • Usually unicellular • When they make pseudopods, they are long and frequently anastomose • Taxa are free-living and symbiotic • Many have mineralized internal cytoskeletons

  34. Foraminifera

  35. Radiolaria

  36. Eukaryotic Domains

  37. Eukaryotic Domains

  38. Fungi • Generally multicellular with complex life histories • Include: mushrooms, molds, and yeasts • Sister group to the animals • Generally are decomposers; some are parasitic and cause disease, particularly in plants

  39. Penicillium, common mold

  40. Mushroom Life History

  41. Yeast

  42. Prototaxites Silurian to Devonian. Gigantic fungus, largest terrestrial organism until advent of trees at the end of the Devonian. Evidence of symbiotic algae in the trunk-like structures, making them lichens.

  43. Honey Mushrooms Covers 2,384 acres in Malhur National Forest of the Blue Mountains in Eastern Oregon. Armillariaostoyae 2400-8650 years old

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