Figure 26.21

1. Figure 26.21 Eukarya Land plants Dinoflagellates Forams Green algae Diatoms Ciliates Red algae Amoebas Cellular slime molds Euglena Trypanosomes Animals Leishmania Fungi Green nonsulfur bacteria Sulfolobus Thermophiles (Mitochondrion) Spirochetes Chlamydia Halophiles COMMON ANCESTOR OF ALL LIFE Green sulfur bacteria Bacteria Methanobacterium Cyanobacteria Archaea (Plastids, including chloroplasts)

2. Prokaryotes vs. Eukaryotes • Unicellular, some colonial • Typically 0.5um diameter • Various shapes • Well organized, all life functions are within one cell

4. Bacterial Shapes

5. Domain Archea • Share some traits with Bacteria and some with eukaryotes

6. The Archaea • Live in extreme environments • Extremophiles • Extreme halophile • Extreme thermophile • Methanogens

7. Domain Bacteria • Include the majority of familiar bacteria • Some are pathogenic • Some are beneficial

8. Cell Structure • Cell wall, Bacteria have peptidoglycan • Gram staining can divide into 2 groups • Gram positive – simple walls, less peptidoglycan • Gram negative – less peptidoglycan, structurally more complex, outer layer of lipopolysaccharide • Capsule or slime layer • Protect against dehydration, stick to surface, shield against attacks by immune systems • Motility by flagella • Fimbraeused to attach cell to surface • One large, circular DNA

9. A few examples of Bacterial Types

10. Roles in the Biosphere • Chemical Recycling • Carbon cycle • Nitrogen cycle • Ecological Interactions • Symbiotic relationships • Pathogens

11. Domain Eukarya • Protista • Fungi • Planta • Animalia

12. Protista • Remember that the field of taxonomy is constantly evolving • Eukarya is divided into 5 supergroups that include planta, animalia, fungi and protista • Most protista are unicellular • All are eukaryotic

14. Excavata • Based on morphological studies of the cytoskeleton • Some have “excavated” feeding groove • Each group is monophyletic • Diplomonads/Parabasalids – lack plastids, have modified mitochondria, often anaerobic • Giardia, Trichomonas • Euglenozoans – rod or crystalline structure inside the flagella • Kinetoplastids - Trypanosoma • Euglenid - Euglena

16. Chromalveolates • Evolved from Secondary Endosymbiosis – common ancestor engulfed a single celled red algae • Monophyletic groups • Alveolates, Stramenopile

17. Alveolates • Membrane bound sacs under the plasma membrane • Dinoflagellates – cellulose plates, groves for flagella • Apicomplexans – complex life cycle, animal parasites • Ciliates – use cilia for movement, feeding; two types of nuclei and conjugation

19. Conjugation in ciliates

20. Stramenopile • Important photosynthetic organisms • Characteristic flagellum with numerous, hairlike projections • Diatoms, Golden and Brown algae, Oomycetes

21. Diatom • Unicellular algae • Wall made of silica • Diatomaceous earth • 100,000 living species

22. Golden Algae • Yellow and brown carotenoids • Biflagellated • Mostly unicellular, some colonial

23. Brown Algae • Multicellular marine ‘seaweed’ • Carotenoid pigments • Thallus - plantlike algal body • No stem, root or leaves • Leaflike blades with airfilled floats, and holdfast • Food, thickening agent

24. Alteration of Generations

25. Oomycetes • Water mold, white rust, downy mildew • Previously fungi • Cell walls are cellulose • Convergent evolution • No plastids, no photosynthesis • Phytophthora – caused potato blight in 19th century, known as the Irish famine

26. Rhizarians • Defined by similarity in their DNA • Vary in morphology • Monophyletic group • Radiolarians • Forams or foraminifera • Cercozoans • Often referred to as amoebas because have threadlike pseudopodia

27. Red and Green Algae • 475 mya, a heterotrophic protist acquired a cyanobacterialendosymbiont = red and green algae • Archaeplastida – red, green algae and land plants evolved from a common ancestor

28. Red Algae • Red color due to phycoerythrin, masks chlorophyll • Pigments absorb red/green light which absorb deeper • Multicellular, diverse lifecycles • Porphyra or Nori

29. Green Algae • Cellular structure similar to that of land plants

30. Unikonts • Related to fungi and animals, very diverse • Some research says these were the first eukaryotes to diverge from other eukaryotes. • Amoebozoans – lobe shaped pseudopodia • Entamoeba– parasitic • Gymnamoeba - soil, freshwater, marine • Slime molds – cellular and plasmodial

31. Plasmodial Slime Mold Life Cycle

33. Plants • Land plants evolved from green algae ancestor • Adaptations for movement to land • Ability to survive out of water • Brighter light • More carbon dioxide that water • Soil rich in nutrients • Few herbivores and pathogens in the beginning • Challenges to living out of water • Scarcity of water • Lack of structural support

34. Four traits that appear in land plants, but not in ancestral algae

35. Alternation of generations and multicellular, dependent embryos

36. 2. Walled spores produced in sporangia

37. 3. Multicellular Gametangia

38. 4. Apical Meristems

39. Table 29.1

41. Moss • Moss consists of gametophytes • Blades are often one cell thick • Often have a thick cuticle

43. Liverworts • Liver-shaped gametophytes are elevated on thallus • Marchantia

44. Hornwort • Long tapered sporophyte • Lacks seta, only sporangium is present

45. Seedless Vascular Plants • Sperm are flagellated and must swim through a film of water to fertilize the egg • Lycophyta – club mosses, spike moss and quillworts • Pterphyta – ferns, horsetails, Psilophyta (whisk ferns)

46. Lycophyta • Often are epiphytes – use other plants as substrate but are not parasites • Upright stems with small leaves

47. Pterophyta • Ferns, Horsetails, Whisk ferns

48. Importance of Seedless Plants • Devonian and Carboniferous periods, forming the first forests • Rapidly removed carbon dioxide from atmosphere, resulting in glacial periods • Eventually became coal

49. Adaptations of Seed Plants

50. Seed Plants • Gymnosperms – naked seeds on cones • Ginkgophyta • Cycadophyta • Gnetophyta • Coniferophyta • Angiosperms • Anthophyta – flowering plants