ORIGIN OF LIFE: ORIGIN OF LIFE How did it happen?


ORIGIN OF LIFE: ORIGIN OF LIFE Four types of organic compounds carbohydrates short chains of carbons (with H and O)


ORIGIN OF LIFE: ORIGIN OF LIFE Four types of organic compounds carbohydrates short chains of carbons (with H and O) monosaccharides disaccharides polysaccharides


ORIGIN OF LIFE: ORIGIN OF LIFE Four types of organic compounds carbohydrates short chains of carbons (with H and O) monosaccharides disaccharides polysaccharides examples sugar starch cellulose


ORIGIN OF LIFE: ORIGIN OF LIFE Four types of organic compounds carbohydrates short chains of carbons (with H and O) lipids long chains of fatty acids


ORIGIN OF LIFE: ORIGIN OF LIFE Four types of organic compounds carbohydrates short chains of carbons (with H and O) lipids long chains of fatty acids saturated unsaturated


ORIGIN OF LIFE: ORIGIN OF LIFE Four types of organic compounds carbohydrates lipids long chains of fatty acids saturated unsaturated examples fats waxes phospholipids


ORIGIN OF LIFE: ORIGIN OF LIFE Four types of organic compounds carbohydrates lipids proteins chains of amino acids


ORIGIN OF LIFE: ORIGIN OF LIFE Four types of organic compounds carbohydrates lipids proteins chains of amino acids - N-C-C What do they do? structure enzymes - regulate all cellular activity


ORIGIN OF LIFE: ORIGIN OF LIFE Four types of organic compounds carbohydrates lipids proteins nucleic acids chains of nucleotides nucleotides phosphate 5 carbon sugar nitrogenous base


ORIGIN OF LIFE: ORIGIN OF LIFE Four types of organic compounds carbohydrates lipids proteins nucleic acids chains of nucleotides nucleotides examples : DNA and RNA


ORIGIN OF LIFE: ORIGIN OF LIFE Stanley Miller and Harold Urey (1953) early experiment with primitive atmosphere


ORIGIN OF LIFE: ORIGIN OF LIFE Stanley Miller and Harold Urey (1953) early experiment with primitive atmosphere included methane, hydrogen, water vapor, ammonia in reaction vessel and added energy


ORIGIN OF LIFE: ORIGIN OF LIFE Stanley Miller and Harold Urey (1953) early experiment with primitive atmosphere included methane, hydrogen, water vapor, ammonia in reaction vessel and added energy products synthesized include: alanine glycine glutamic acid aspartic acid other organic compounds


ORIGIN OF LIFE: ORIGIN OF LIFE Stanley Miller and Harold Urey (1953) Later research has produced 18 of 20 amino acids, purines, pyrimidines, sugars, etc. by similar techniques


ORIGIN OF LIFE: ORIGIN OF LIFE Stanley Miller and Harold Urey (1953) Later research has produced 18 of 20 amino acids, purines, pyrimidines, sugars, etc. by similar techniques Until 1985 we thought that Miller and Urey had the single answer to the origin of life


ORIGIN OF LIFE: ORIGIN OF LIFE Stanley Miller and Harold Urey (1953) Later research has produced 18 of 20 amino acids, purines, pyrimidines, sugars, etc. by similar techniques Until 1985 we thought that Miller and Urey had the single answer to the origin of life Halley’s comet: Soviet and European spacecraft - 20% organic molecules


ORIGIN OF LIFE: ORIGIN OF LIFE chemical 'evolution' on Earth stable molecules survive


ORIGIN OF LIFE: ORIGIN OF LIFE chemical 'evolution' on Earth other possibilities debris from other extraterrestrial species? from Mars?


ORIGIN OF LIFE: ORIGIN OF LIFE chemical 'evolution' on Earth stable molecules survive extraterrestrial - in lab if cool ammonia, methane, water vapor to -440F and irradiate with UV light, get organic molecules (Murchison meteorite contains same amino acids obtained by Miller in same proportions)


ORIGIN OF LIFE: ORIGIN OF LIFE chemical 'evolution' on Earth stable molecules survive extraterrestrial - cool molecules and irradiate to get organic molecules find organic molecules in meteorites (55 amino acids) and in interplanetary dust


ORIGIN OF LIFE: ORIGIN OF LIFE chemical 'evolution' on Earth stable molecules survive extraterrestrial - cool molecules and irradiate to get organic molecules find organic molecules in meteorites (55 amino acids) and in interplanetary dust Earth bombarded with extraterrestrial objects for 0.5 billion years --andgt; 1016 tons of organic matter


ORIGIN OF LIFE: ORIGIN OF LIFE Earth bombarded with extraterrestrial objects for 0.5 billion years --andgt; 1016 tons of organic matter could accumulate a layer of organic molecules 3 feet deep covering Earth (1 gm/liter of organic molecules)


ORIGIN OF LIFE: ORIGIN OF LIFE chemical 'evolution' on Earth shallow warm pools deep sea thermal vents


ORIGIN OF LIFE: ORIGIN OF LIFE chemical 'evolution' on Earth shallow warm pools deep sea thermal vents chemosynthetic thermophiles - Pace, 1991


ORIGIN OF LIFE: ORIGIN OF LIFE chemical 'evolution' on Earth shallow warm pools deep sea thermal vents chemosynthetic thermophiles - Pace, 1991 How were cells assembled?


ORIGIN OF LIFE: ORIGIN OF LIFE phospholipids will form hollow spheres


ORIGIN OF LIFE: ORIGIN OF LIFE phospholipids will form hollow spheres amino acids form polypeptides (protein)


ORIGIN OF LIFE: ORIGIN OF LIFE phospholipids will form hollow spheres amino acids form polypeptides (protein) some amino acids are energy processing compounds can actually decompose glucose and other molecules


ORIGIN OF LIFE: ORIGIN OF LIFE phospholipids will form hollow spheres amino acids form polypeptides (protein) some amino acids are energy processing compounds can actually decompose glucose and other molecules but even these collections of molecules are not alive!


ORIGIN OF LIFE: ORIGIN OF LIFE Chemical combinations are not alive because have no mechanism for heredity


ORIGIN OF LIFE: ORIGIN OF LIFE Chemical combinations are not alive because have no mechanism for heredity DNA functions only to store information


ORIGIN OF LIFE: ORIGIN OF LIFE Chemical combinations are not alive because have no mechanism for heredity DNA functions only to store information Proteins require nucleic acid to be formulated in the next generation


ORIGIN OF LIFE: ORIGIN OF LIFE Chemical combinations are not alive because have no mechanism for heredity DNA functions only to store information Proteins require nucleic acid to be formulated in the next generation What type of molecule could function as both an information carrier and a catalyst (protein)?


ORIGIN OF LIFE: ORIGIN OF LIFE What type of molecule could function as both an information carrier and a catalyst (protein)?


ORIGIN OF LIFE: ORIGIN OF LIFE What type of molecule could function as both an information carrier and a catalyst (protein)? RNA some types of RNA can act like protein (catalyze reactions) and DNA (store information) Tom Cech


ORIGIN OF LIFE: ORIGIN OF LIFE What type of molecule could function as both an information carrier and a catalyst (protein)? RNA some types of RNA can act like protein (catalyze reactions) and DNA (store information) Tom Cech Biological Evolution can occur!


ORIGIN OF LIFE: ORIGIN OF LIFE Earliest cells were not very good cells


ORIGIN OF LIFE: ORIGIN OF LIFE Earliest cells were not very good cells heterotrophs or chemoautotrophs early nucleic acids probably made mistakes low energy yield from organic molecules


ORIGIN OF LIFE: ORIGIN OF LIFE Earliest cells were not very good cells heterotrophs or chemoautotrophs early nucleic acids probably made mistakes low energy yield from organic molecules Primordial Soup how long would the primordial soup last?


ORIGIN OF LIFE: ORIGIN OF LIFE The First Living Cells ? 3.8 billion years?Greenland (southwest), Pflug and Jaeschke-Boyer, 1979; - unicells, filaments, colonies; apparent sheath, cell wall and cell interior; BUT: chemical evidence is inconclusive due to warming of rock and carbon isotope ratios not reliable


ORIGIN OF LIFE: ORIGIN OF LIFE 3.8 bya Greenland? 3.5 bya Australia (western) Walter, Buick, Dunlop, 1980 Dunlop, Muir and Groves, 1978 Schopf, 1983 unicellular, filamentous, colonies chemical evidence good, 12C enriched evidence of photosynthesis also amino acids, fatty acids, etc


ORIGIN OF LIFE: ORIGIN OF LIFE Stromatolites chemical fossils produced by microorganisms


ORIGIN OF LIFE: ORIGIN OF LIFE Stromatolites chemical fossils produced by microorganisms remove CO2 by photosynthesis results in a precipitation of CaCO3


ORIGIN OF LIFE: ORIGIN OF LIFE Stromatolites chemical fossils produced by microorganisms remove CO2 by photosynthesis results in a precipitation of CaCO3 still produced today in Bermuda and Australia


ORIGIN OF LIFE: ORIGIN OF LIFE Banded Iron Formation Ferrous irons in solution (Fe++)


ORIGIN OF LIFE: ORIGIN OF LIFE Banded Iron Formation Ferrous irons in solution (Fe++) When oxygen produced in photosynthesis bonds with iron, get ferric oxides


ORIGIN OF LIFE: ORIGIN OF LIFE Banded Iron Formation Ferrous irons in solution (Fe++) When oxygen produced in photosynthesis bonds with iron, get ferric oxides When ferric oxides precipitate get Banded Iron Formation


ORIGIN OF LIFE: ORIGIN OF LIFE Banded Iron Formation Ferrous irons in solution (Fe++) When oxygen produced in photosynthesis bonds with iron, get ferric oxides When ferric oxides precipitate get Banded Iron Formation produced from 3.4-1.8 bybp (most from 2.5-2.0 bybp)


ORIGIN OF LIFE: ORIGIN OF LIFE 3.8 bya Greenland? 3.5 bya Australia (western) 3.1-3.4 bya South Africa Fig Tree series, similar in appearance to modern bacteria and cyanobacteria photosynthesis present


ORIGIN OF LIFE: ORIGIN OF LIFE 3.8 bya Greenland? 3.5 bya Australia (western) 3.1-3.4 bya South Africa 3.2 bya Bulawayo S.Africa


ORIGIN OF LIFE: ORIGIN OF LIFE 3.8 bya Greenland? 3.5 bya Australia (western) 3.1-3.4 bya South Africa 3.2 bya Bulawayo S.Africa 2.7 bya Great Slave Lake (NW territories)


ORIGIN OF LIFE: ORIGIN OF LIFE 3.8 bya Greenland? 3.5 bya Australia (western) 3.1-3.4 bya South Africa 3.2 bya Bulawayo S.Africa 2.7 bya Great Slave Lake (NW territories) 2 bya Gunflint Ontario-Minnesota


ORIGIN OF LIFE: ORIGIN OF LIFE 3.8 bya Greenland? 3.5 bya Australia (western) 3.1-3.4 bya South Africa 3.2 bya Bulawayo S.Africa 2.7 bya Great Slave Lake (NW territories) 2 bya Gunflint Ontario-Minnesota ABOVE ARE ALL PROKARYOTES


ORIGIN OF LIFE: ORIGIN OF LIFE What about eukaryotic cells?


ORIGIN OF LIFE: ORIGIN OF LIFE What about eukaryotic cells? earliest eukaryotes to about 2.1 bya (Han and Runnegar, 1992) from Michigan resemble modern green algae


ORIGIN OF LIFE: ORIGIN OF LIFE What about eukaryotic cells? earliest eukaryotes to about 2.1 bya Endosymbiotic theory eukaryotic cell from fusion of two prokaryotic cells


ORIGIN OF LIFE: ORIGIN OF LIFE What about eukaryotic cells? earliest eukaryotes to about 2.1 bya Endosymbiotic theory eukaryotic cell from fusion of two prokaryotic cells DNA and RNA of chlorplasts and mitochondria in eukaryotes are similar to those of prokaryotic cells produce their own energy, capable of independent division


TIME LINE: TIME LINE 4.6 bya Earth formed


TIME LINE: TIME LINE 4.6 bya Earth formed 4.5 bya oceanic crust formed


TIME LINE: TIME LINE 4.6 bya Earth formed 4.5 bya oceanic crust formed 4.0 bya continental crust


TIME LINE: TIME LINE 4.6 bya Earth formed 4.5 bya oceanic crust formed 4.0 bya continental crust 3.8-3.5 bya first life


TIME LINE: TIME LINE 4.6 bya Earth formed 4.5 bya oceanic crust formed 4.0 bya continental crust 3.8-3.5 bya first life 3.4 bya beginning of Banded Iron Fm.


TIME LINE: TIME LINE 4.6 bya Earth formed 4.5 bya oceanic crust formed 4.0 bya continental crust 3.8-3.5 bya first life 3.4 bya beginning of Banded Iron Fm. 2.5-2.1 bya first glaciation


TIME LINE: TIME LINE 4.6 bya Earth formed 4.5 bya oceanic crust formed 4.0 bya continental crust 3.8-3.5 bya first life 3.4 bya beginning of Banded Iron Fm. 2.5-2.1 bya first glaciation 2.1 bya first eukaryotes


TIME LINE: TIME LINE 4.6 bya Earth formed 4.5 bya ocean crust 4.0 bya continental crust 3.8-3.5 bya origin of life photosynthesis 3.4 bya Banded Iron Formation (1st) 2.5 bya glaciation 2.1 bya first eukaryotes