1. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE

2. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
HOW DID LIFE ORIGINATE?
SPONTANEOUS GENERATION
LIFE ARISING FROM NON-LIVING MATTER
LONG BELIEVED AS THE ACCEPTED EXPLANATION OF ORIGINATION OF LIFE
EXPERIMENTS EVENTUALLY SHOWED IT TO BE IMPOSSIBLE
ORIGINATION OF LIFE HAD TO BE A STEP-WISE PROCESS

3. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
MILLER AND UREY’S EXPERIMENT
ATTEMPTED TO EXPLAIN/SHOW HOW EARLY EARTH COULD HAVE GIVEN RISE TO ORGANIC COMPOUNDS

4. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
THE FIRST POLYMERS FORMED ON HOT ROCKS OR CLAY
EXPERIMENTS HAVE SHOWN HEAT ENERGY ON HOT SURFACES PROVIDES SUFFICIENT ACTIVATION ENERGY FOR DEHYDRATION SYNTHESIS REACTIONS

5. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
THE FIRST GENETIC MATERIAL WAS PROBABLY RNA
WHY?
RIBOZYMES
RNA THAT ACTED AS ENZYMES

6. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
MOLECULAR COOPERATIVES ENCLOSED BY MEMBRANES PROBABLY PRECEDED THE FIRST REAL CELLS
EXPERIMENTS HAVE SHOWN THAT IN AQUEOUS ENVIRONMENTS, CERTAIN KINDS OF MOLECULES, INCLUDING LIPIDS AND POLYPEPTIDES, CAN SELF-ASSEMBLE INTO MICROSCOPIC SPHERES FILLED WITH FLUID

7. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
PROKARYOTES WERE PROBABLY THE FIRST FORMS OF LIFE BECAUSE…
SIMPLEST FORM OF LIFE (UNICELLULAR PROKARYOTE)
HAVE INHABITED EARTH FOR BILLIONS OF YEARS
IMMENSE NUMBER OF PROKARYOTES EXIST

8. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
TWO MAIN FORMS OF PROKARYOTES
ARCHAEA VS. BACTERIA (EUBACTERIA)
EXTREMELY DIFFERENT FORMS OF BACTERIA
GENETIC DATA SUPPORTS 3 DOMAIN SYSTEM
BACTERIAL CELL WALLS CONTAIN PEPTIDOGLYCAN; NOT FOUND IN ARCHAEA
BACTERIAS COME IN A VARIETY OF SHAPES/STRUCTURES

9. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
BACTERIAS

10. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
PROKARYOTES OBTAIN NOURISHMENT IN A VARIETY OF WAYS

11. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
PROKARYOTIC NOURISHMENT
“HETEROTROPH HYPOTHESIS” VS CHEMOAUTOTROPHIC HYPOTHESIS

12. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
ARCHAEA CAME FIRST BECAUSE
THRIVE IN EXTREME ENVIRONMENTS AND THE OCEAN
EXTREME HALOPHILES  SALT LOVERS
EXTREME THERMOPHILES  HEAT LOVERS
METHANOGENS  LIVE IN ANAEROBIC ENVIRONMENTS AND GIVE OFF METHANE AS A WASTE PRODUCT
JUST BECAUSE THEY CAME FIRST, DOESN’T MEAN THEY ARE SO OLD THEY ARE EXTINCT!! (ANCIENT DOES NOT EQUAL EXTINCT)

13. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
DIVERSE STRUCTURAL FEATURES HELP PROKARYOTES THRIVE ALMOST ANYWHERE
PROKARYOTIC FLAGELLUM

14. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
DIVERSE STRUCTURAL FEATURES HELP PROKARYOTES THRIVE ALMOST EVERYWHERE
PILI  TINY APPENDAGES THAT HELP BACTERIA ATTACH TO EACH OTHER AND SURFACES
ENDOSPORES  SPECIALIZED “INNER CELL” THAT CAN SURVIVE HARSH CONDITIONS, MAY REMAIN DORMANT FOR CENTURIES

15. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
CYANOBACTERIA (A.K.A. BLUE-GREEN ALGAE)
SPECIFIC TYPE OF BACTERIAL CELL THAT CAN PERFORM PHOTOSYNTHESIS

16. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
SOME BACTERIA CAUSE DISEASE
PATHOGENS  DISEASE-CAUSING AGENTS
EXOTOXINS  TOXIC PROTEINS SECRETED BY BACTERIAL CELLS
ENDOTOXINS  COMPOUNDS OF THE CELL WALLS OF CERTAIN BACTERIA
SANITATION, ANTIBIOTICS, EDUCATION ARE WAYS TO DEFEND AGAINST BACTERIAL DISEASE

17. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
DISEASE CAUSING BACTERIA

18. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
BACTERIA CAN BE USED AS BIOLOGICAL WEAPONS
**PATHOGENIC PROKARYOTES ARE IN THE MINORITY, MOST PROKARYOTES ARE VITAL TO OUR WELL BEING
EXAMPLES:
NITRIFYING BACTERIA, DECOMPOSERS, ETC…

19. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
THE EUKARYOTIC CELL PROBABLY ORIGINATED AS A COMMUNITY OF PROKARYOTES
MEMBRANE INFOLDING  THE ORGANELLES (NOT MITOCHONDRIA AND CHLOROPLAST) ARISE FROM THE INWARD FOLDS OF THE PLASMA MEMBRANE OF A PROKARYOTIC CELL

20. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
THE EUKARYOTIC CELL PROBABLY ORIGINATED AS A COMMUNITY OF PROKARYOTES
ENDOSYMBIOSIS  ONE SPECIES LIVING WITHIN ANOTHER
EXAMPLES??

21. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
PROTISTS
A DIVERSE GROUP OF MOSTLY UNICELLULAR EUKARYOTES; SOME PROTISTS ARE PHOTOSYNTHETIC, OTHERS ARE HETEROTROPHIC

22. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE

23. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
TWO GENERIC TYPES
OF PROTISTS
ANIMAL-LIKE PROTISTS
A.K.A. PROTOZOA
PROTISTS THAT LIVE PRIMARILY BY INGESTING FOOD, A HETEROTROPHIC MODE OF NUTRITION THAT IS “ANIMAL-LIKE”
PLANT-LIKE PROTISTS
A.K.A. ALGAE
PROTISTS THAT LIVE BY SYNTHESIZING FOOD FROM CARBON DIOXIDE AND WATER, AN AUTOTROPHIC MODE OF NUTRITION THAT IS “PLANT-LIKE”

24. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
GROUPS OF PROTISTS
FLAGELLATES
PSEUDOPODIA
CILIATES

25. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
PHOTOSYNTHETIC PROTISTS ARE CALLED ALGAE
ALGAE  DEF??
DINOFLAGELLATES
DIATOMS
GREEN ALGAE
PROBABLY MOST INTERESTING EVOLUTIONARILY, BECAUSE IT IS PROBABLY THE ANCESTOR OF LAND PLANTS

26. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
SEAWEEDS ARE MULTICELLULAR MARINE ALGAE
THREE TYPES OF SEAWEED
BROWN ALGAE
EXAMPLE: KELP  CAN GROW ABOUT 100 METERS)
RED ALGAE
SEE PICTURE TO RIGHT
GREEN ALGAE

27. THE ORIGIN AND EVOLUTION OF MICROBIAL LIFE
MULTICELLULAR LIFE MAY HAVE EVOLVED FROM COLONIAL PROTISTS