MonthDayLecture Oct2Eubacteria and archebacteria 4Protists 6No class-Homecoming! 9Plants 11Fungi 13The coral reef 16Animals I 18Animals II
Outline 1.Diversity of life 2.The three domains of life 3.Bacteria and Archaea 4.Biodiversity
Evolutionary Tree extreme thermophiles halophiles methanogens cyanobacteria ARCHAEBACTERIA PROTISTANS FUNGI PLANTS ANIMALS club fungi sac fungi zygospore- forming fungi echino- derms chordates annelids mollusks flatworms sponges cnidarians flowering plants conifers horsetails lycophytes ferns bryophytes sporozoans green algae amoeboid protozoans slime molds ciliates red algae brown algae chrysophytes cycads ginkgos rotifers arthropods round- worms chytrids oomycotes euglenoids dinoflagellates Gram-positive bacteria spirochetes chlamydias proteobacteria ? crown of eukaryotes (rapid divergences) molecular origin of life EUBACTERIA parabasalids diplomonads (e.g., Giardia) (alveolates) (stramenopiles) chlorophytes kinetoplastids extreme (e.g., Trichomonas) Figure Page 321
Five Kingdoms BacteriaProtistsPlantsFungiAnimals Earliest organisms
Three domains Bacteria Earliest organisms ArchaeaEukarya
three domains
Prokaryotes Includes Bacteria and Archaea
What roles do prokaryotes play in our lives? or Why we care about prokaryotes…
Characteristics of prokaryotes 1.Form
Coccus Bacillus Filaments
Characteristics of prokaryotes 1.Form 2.Cell structure
A prokaryote cell...
Characteristics of prokaryotes 1.Form 2.Cell structure 3.Locomotion
Whip-like flagella: swimming motion
Internal fibrils: rolling motion
Adjustable gas vesicles: floating or sinking motion
Characteristics of prokaryotes 1.Form 2.Cell structure 3.Locomotion 4.Peptidoglycan cell walls (Bacteria) Protein cell walls (Archaea)
A prokaryote cell...
Characteristics of prokaryotes 1.Form 2.Cell structure 3.Locomotion 4.Peptidoglycan cell walls (Bacteria) Protein cell walls (Archaea) 5. Asexual reproduction
Prokaryotes reproduce asexually through fission, but there are some mechanisms for genetic recombination –Transformation –Conjugation –Transduction
Characteristics of prokaryotes 1.Form 2.Cell structure 3.Locomotion 4.Peptidoglycan cell walls (Bacteria) Protein cell walls (Archaea) 5. Asexual reproduction
Prokaryotes have many “lifestyles”... Anaerobic versus aerobic
Prokaryotes have many “lifestyles”... Anaerobic versus aerobic respiration Obligate anaerobes Facultative anaerobes Obligate aerobes
Nutritional modeEnergyCarbon PhotoautotrophLightCO 2 ChemoautotrophChemicalsCO 2 PhotoheterotrophLightOrganic material ChemoheterotrophOrganic material Organic material
Photoautotrophs These bacteria use light for energy and CO 2 for carbon.
These bacteria use H 2 SO 4 as an energy source and CO 2 as a carbon source Chemoautotrophs
Photoautotrophs These bacteria use light for energy and CO 2 for carbon.
Chemoheterotrophs These organisms use organic materials for energy and for carbon.
Prokaryotes drive biogeochemical cycles... Nitrogen Carbon Sulfur Other elements: phosphorous, hydrogen, mercury, iron...
Carbon cycle Carbon Cycle
Bacteria can be pathogens... (but not Archaea!) Plant pathogens Animal pathogens
Crown gall—bacterial infection of geranium plant stem
“Strep” “Staph” Anthrax E. coli Salmonella Botulism Tuberculosis Legionnaire’s Leprosy Syphilis and many more...
Bacterial toxins Endotoxins –Released from cell wall when bacteria burst –Rarely fatal –E. coli, samonella poisoning Exotoxins –Released by growing bacteria –Often fatal –Tetanus, botulism, cholera, black plague