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