1. Introduction to Protists

2. First eukaryotic organism thought to have evolved about 1.5 billion years ago Protozoans possible evolved from the 1 st eukaryotes by Endosymbiosis Endosymbiosis – process where one prokaryote lives inside another becoming dependent upon each other Origin of Eukaryotes

3. Membrane-bound nucleus and organelles Chromosomes consist of DNA and histone proteins and occur in pairs. Protists, fungi, plants & animals are composed of eukaryotic cells. Origin of Eukaryotes Eukaryotic cell more complex than prokaryotic cell:

4. Prokaryotic Cells

5. Typical Animal Cell Eukaryotic Animal Cell

6. Typical Plant Cell Eukaryotic Plant Cell

7. Animal Plant mitochondria chloroplasts vacuole Vacuole Functions Storage Support Water Regulation Both cell types have membrane-bounded organelles

8. Infolding of membrane system forming nucleus and ER Origin of Eukaryotes Endomembrane infolding

9. Origin of Eukaryotes Evolution of eukaryotic cell- Endosymbiosis Theory proposed by Mereschkovsky and refines by Margulis- serial endosymbiosis Mitochondria and plastids were prokaryotes that invaded larger cells Endosymbiont, ancestral mitochondria: Aerobic, heterotrophic & prokaryotic

10. Origin of Eukaryotes Ancestral chloroplasts were photosynthetic, prokaryotes that became endosymbionts Relationship began as parasitic or undigested prey Assumed here that endomembrane infolding evolved first, i.e., cell already evolved nucleus, ER, …

11. Endosymbiosis Hypothesis A A prokaryote ingested some aerobic bacteria. The aerobes were protected and produced energy for the prokaryote Chloroplasts Aerobic bacteria Mitochondria Cyanobacteria Prokaryote Animal Cell Plant cell B C D A N N N N

12. Endosymbiosis Hypothesis B Over a long period of time the aerobes became mitochondria, no longer able to live on their own A B C D Chloroplasts Aerobic bacteria Mitochondria Cyanobacteria Prokaryote Animal Cell Plant cell N N N N

13. Endosymbiosis Hypothesis C Some primitive prokaryotes also ingested cyanobacteria, which contain photosynthetic pigments A B C D Chloroplasts Aerobic bacteria Mitochondria Cyanobacteria Prokaryote Animal Cell Plant cell N N N N

14. Endosymbiosis Hypothesis D Cyanobacteria became chloroplasts, unable to live on their own A B C D Chloroplasts Aerobic bacteria Mitochondria Cyanobacteria Prokaryote Animal Cell Plant cell N N N N

15. Secondary Endosymbiosis and Origin of Algal Diversity Algae AB Heterotroph C N N Secondary endosymbiosis N Many membrane layers Algae ABC

16. Fig. 28-02-2 Cyanobacterium Heterotrophic eukaryote Over the course of evolution, this membrane was lost. Red alga Green alga Primary endosymbiosis Secondary endosymbiosis Secondary endosymbiosis Secondary endosymbiosis Plastid Dinoflagellates Apicomplexans Stramenopiles Plastid Euglenids Chlorarachniophytes Secondary Endosymbiosis

17. LUCA model places the archaea as more closely related to eukaryotes than they are to prokaryotes.

18. All three domains seem to have genomes that are chimeric mixes of DNA that was transferred across the boundaries of the domains. Common ancestral community of primitive cells model

19. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Fig. 28.8

20. Excavata Chromalveolata Rhizaria Archaeplastida Unikonta Five Supergroups Red and green algae Slime molds Forams and radiolarians Dinoflagellates, diatoms, golden and brown algae Euglenoids

21. Kingdom Protista Plantae Fungi Animalia Protista Monera prokaryotic eukaryotic

22. Kingdom Protista Eukaryotic Mostly unicellular A very heterogeneous group include both heterotrophic and photoautotrophic forms 11 phyla Lots of disagreements Whittaker = “leftovers”

23. binary fission splits into two asexually multiple fission producing more than two individuals sexually by conjugation (opposite mating strains join & exchange genetic material) Reproduction:

24. 3 informal groups Animal-like protists Fungus-like protists Plant-like (algal) protists Misleading: some change Kingdom Protista ~ 45,000 species

25. Ciliophora Kingdom Animalia Sarcomastigophora Apicomplexa Mastigophora Euglenophyta Kingdom Plantae Chrysophyta Pyrrophyta Myxomycota Kingdom Fungi Kingdom Protista Chlorophyta Phaeophyta Rhodophyta

26. Amoeba Cilliates Flagellates Animal-like Protists 13,000 species

27. Classified by the way they move Animal-like Protists cilia flagella pseudopodia

28. Heterotrophs ingest small food particles & digest it inside food vacuoles containing digestive enzymes

29. Animal-like protists Sarcomastigophora (amoebas, forams, radiolarian) Ciliophora (paramecium) Zoomastigophora (trypansoma) Apicocomplexa (Sporozoa)

30. Phylum Sarcomastigophora “Amoeba” Shell-like glass or calcium carbonate structures Radiating projections Animal-like Protists 13,000 species

31. Note: glass projections

32. Foraminifera Tropics = beaches Most have symbiotic algae

33. Foramenifera: Globigerina ooze Covers about 36% of the ocean floor

34. Phylum Ciliophora (“ciliates”) Largest, most homogeneous Share few characteristics with others Movement coordinated Sex: 8 mating types Animal-like Protists 8,000 species

35. Paramecium

37. Asexual reproduction Binary fission

38. Paramecium reproduction 1. Individuals fuse 2. Micronucleus produces 4 haploid nuclei

39. Paramecium reproduction 4. Mates swap micronuclei 3. One divides by mitosis, 3 disintegrate

40. Paramecium reproduction 5. Syngamy occurs, micronuclei fuse 6. Micronuclei undergo mitosis and form 8 micronuclei

41. Paramecium reproduction 7. Original macronucleus disintegrates; 4 micronuclei dev into new macronuclei 8. After 2 cell divisions w/out nuclear division, the new macro and micronuclei are parceled out into 4 new individuals

42. Phylum Zoomastigophora (“zooflagellates”) Move using flagella Move using flagella:1 to thousands of flagella Some parasites African trypanosomiasis – sleeping sickness – tsetse flyAfrican trypanosomiasis – sleeping sickness – tsetse fly Chagas Disease – kissing bugChagas Disease – kissing bug Leishmaniasis – sand flyLeishmaniasis – sand fly giardiasisgiardiasis Vaccines? change protein coat! Gave rise to animals? Animal-like Protists 1,500 species

43. African sleeping sickness Tsetse fly Trypansoma

44. The Kissing Bug Chagas disease

45. Leishmaniasis Sand fly Leishmania

46. Malaria Mosquito & “victim” Africa = kills 1 million children per year Thousands of sporozoites injected Vaccine? (US support?) Anopheles Mosquito Plasmodium sporozoite gameteocyte

47. Plasmodium, the parasite that causes malaria, spends part of its life in mosquitoes and part in humans.

48. Travel to Malarial Infected Areas

49. Malaria Prevention Quinine DEET Netting Genetically modified fungus

50. Fungus-like Protists Phylum Oomycota (“water molds”; mildew, blights) Some unicellular; others consist of hyphae Decomposers,parasites Cell walls- cellulose Related to algae based on cell wall composition Named after reproductive method 475 species No “septa”

51. water molds

52. Downy Mildew

53. Mildew hyphae

54. Oomycota Reproduction: the “egg fungi”, a relatively large egg cell is fertilized by a smaller “sperm nucleus,” forming a resistant zygote.

55. Fungus-like Protists Phylum Myxomycota (“slime molds”) Bizarre Bright colors Moving “slime” mass Acellular body 550 species

56. Fungus-like Protists 475 species Downey mildew Slime molds Mildew Water molds Blights

59. Slime Mold Maze The slime mold starts out evenly spread through the maze, but when food sources are placed at two ends, the slime mold retracts from everywhere but the shortest path.

60. The Blob Unidentified Growing Object “Big as a platter, foamy and creamy and pale yellow.” Died of sunstroke and nicotine poisoning

61. Plasmabot

62. cellular slime molds

63. Plant-like Protists Dinoflagellates Diatoms Euglena Cocolithophore Green algae Brown Algae Red algae Diatoms Dinoflagellates Radiolarian Cocolithophore

64. Plant-like Protists Phylum Pyrrophyta (“dinoflagellates”) 1,100 species Cause “red tide” Some live in corals Marine and Freshwater

65. Zooxanthellae in Coral Polyp

66. Pyrocystis fusiformis Bioluminescence

67. HAB (harmful algal blooms) can result in PSP (paraletic shellfish poisoning) Gonyaulax polyhedra, Gymnodium

69. The numbers are representative values of the concentration in the tissues of dinoflagellate toxin (ppm) Primary producers Primary consumers Secondary consumers Tertiary consumers 0.04 ppm 0.23 ppm 2.07 ppm 13.8 ppm

70. Plant-like Protists Phylum Chrysophyta (“diatoms & golden algae”) Link to green algae 13,000 species

71. Diatom - Akashiwo sanguinea Domoic acid 2009 Washington State 10,000 seabirds deaths Alfred Hitchkock “The Birds” HAB- diatoms

72. epithecate hypothecate Diatom Reproduction- asexual auxospore Discards shell and grows new one

73. Phylum Euglenophyta (“euglenoids”) Plant-like Protists 800 species

74. Division Chlorophyta “Green algae” Most freshwater or terrestrial Some marine 7,000 species

75. Halimeda opuntia Chlorophyta: Green Algae Caulerpa racemosa Caulerpa sertularioides Dictyosphaeria cavernosa Codium edule

76. Division Phaeophyta “Brown algae” Marine habitats Example: giant kelp forests 1,500 species

77. Example of complex morphology: Macrocystis a.holdfast - attaches to substrate b.stipe c.blade - main organ of photosynthesis d.bladder - keeps blades near the surface Blade Bladder Stipe Holdfast

78. Laminaria Life Cycle

81. Sargassum polyphyllum Sargassum echinocarpum Phaeophyta: Brown Algae Turbinaria ornata Padina japonica Hydroclathrus clathratus

82. Division Rhodophyta “Red algae” Most in marine habitats 4,000 species

83. Hypnea chordacea Asparagopsi s taxiformis Galaxaura fastigiata Acanthophora spicifera Ahnfeltia concinna Rhodophyta: Red Algae

85. Halimeda opuntia Acanthophora Avrainvillae Eucheuma Gracilaria Hypnea Kappaphycus

86. Super Sucker

87. Inquiry 1.Identify 2 organisms that have a mutualistic symbiotic relationship with an other organism. 2.What threat do alien algae pose? 3.What is PSP? 4.What is biomagnification? 5.Identify 2 autotrophic bacteria.