 Earth is estimated to be about 4.6 billion  years old. Atmosphere was very harsh.     Very hot.     Lot’s of water va...
Origin of Life Scientists had hard time  finding ancient evidence of  life 45 years ago we found out  why. Most ancient...
How did life begin?   Extraterrestrial origin   Creation ( ID )—”divine forces”   From non-living matter “Chemical Evol...
Origin of Life’s Chemicals Miller-Urey Experiment that  recreated atmosphere  of early Earth Hypothesis: Can  organic c...
Self Assembly   Molecules can    spontaneously form into    droplets—oil and water   Protein + water =    “microspheres”...
1 genetic material- RNA      st Earth’s early surface was inhospitable  due to immense UV radiation Deep sea vents on th...
Road to Modern Organisms 1st    life was bacteria unicellular prokaryotes Photosynthesis changed Earth’s  atmosphere re...
GENERAL EVOLUTION TIMELINE   EARTH   MOLECULES   PROKARYOTES   SINGLE-CELLED EUKARYOTES   MULTICELLULAR ORGANISMS   ...
       Timeline of Life           Earth formation        •     4500 million (4.5 billion) years ago           Miller’s ...
   First life on Earth     • 3500 million years ago     • bacterial (prokaryotic) cell   Evolution of cyanobacteria     ...
   First multicellular organisms     • 2000 million years ago     • eukaryotic algae     • OXYGEN IN ATMOSPHERE to form p...
   First marine vertebrates and land plants     • 450 million years ago     • Jawless fish     • Giant ferns   First lan...
   First gymnosperms     • 290 million years ago     • naked seeds     • Evergreen trees   First mammal like reptiles   ...
   First dinosaurs     • 220 million years ago     • Dinosaurs dominated in the Jurassic period   First birds evolve    ...
   Very early primates    • 64 million years ago    • Order of mammals that apes, monkeys, and      humans belong to.   ...
   Lucy fossil     • 4 million years ago     • earliest hominid—common ancestor to humans       and apes (gorillas, orang...
Ma originsof life
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Ma originsof life

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Transcript of "Ma originsof life"

  1. 1.  Earth is estimated to be about 4.6 billion years old. Atmosphere was very harsh.  Very hot.  Lot’s of water vapor in the atmosphere.  Volcanic activity.  NO BREATHABLE OXYGEN GAS!  Carbon dioxide, ammonia, hydrogen gas, were present We needed to find earliest evidence of life for clues to what it was
  2. 2. Origin of Life Scientists had hard time finding ancient evidence of life 45 years ago we found out why. Most ancient life was Cyanobacteria fossil about microscopic=microfossils 1,000,000,000 (1 billion) years old found in stromatolites Oldest microfossil3.5 billion years old 1st organisms were bacteria
  3. 3. How did life begin? Extraterrestrial origin Creation ( ID )—”divine forces” From non-living matter “Chemical Evolution” Main proposal as to how this happened Organic compounds (microspheres) Assemble to create 1st bacterial cell Some bacterial cells became organelles of others to form eukaryotic cells Eukaryotic cells join to form multicellular organisms
  4. 4. Origin of Life’s Chemicals Miller-Urey Experiment that recreated atmosphere of early Earth Hypothesis: Can organic compounds form in early Earth conditions? Results: amino acids, nucleotides, lipids, carbohydrate pieces out
  5. 5. Self Assembly Molecules can spontaneously form into droplets—oil and water Protein + water = “microspheres” Solution with lipids will self assemble into a lipid bilayer Droplets can enclose watery solution different from surroundings BOTH SMALL SPHERES RESEMBLE CELL MEMBRANES!
  6. 6. 1 genetic material- RNA st Earth’s early surface was inhospitable due to immense UV radiation Deep sea vents on the sea floor may have provided sheltered location for life. RNA can form in labs under conditions similar to areas near deep sea vents Oldest living prokaryotes found there today…
  7. 7. Road to Modern Organisms 1st life was bacteria unicellular prokaryotes Photosynthesis changed Earth’s atmosphere released O2 - cyanobacteria!!!! 2nd was unicellular eukaryotes Endosymbiotic Theory Then multicellular organisms
  8. 8. GENERAL EVOLUTION TIMELINE EARTH MOLECULES PROKARYOTES SINGLE-CELLED EUKARYOTES MULTICELLULAR ORGANISMS MARINE INVERTEBRATES MARINE VERTEBRATES LAND PLANTS LAND VERTEBRATES REPTILES GYMNOSPERMS--EVERGREENS MAMMALS DINOSAURS BIRDS ANGIOSPERMS-- FLOWERING PLANTS DINOSAUR EXTINCTION EARLY PRIMATES ANTHROPOIDS HUMANS
  9. 9.  Timeline of Life  Earth formation • 4500 million (4.5 billion) years ago  Miller’s molecules • 4000 million (4.0 billion) years ago • amino acids • proteins • carbohydrates • nucleic acids • mass extinction
  10. 10.  First life on Earth • 3500 million years ago • bacterial (prokaryotic) cell Evolution of cyanobacteria • Blue-green bacteria • Photosynthesis • Oxygen production! First single eukaryotic cells • 2200 million years ago • Organelles such as mitochondria and chloroplasts made of prokaryotic cells. Have their own DNA
  11. 11.  First multicellular organisms • 2000 million years ago • eukaryotic algae • OXYGEN IN ATMOSPHERE to form protective ozone layer  O3  absorbs UV light  protects DNA from mutation  allowed life on land First invertebrate marine animals • 500 million years ago • Jellyfish
  12. 12.  First marine vertebrates and land plants • 450 million years ago • Jawless fish • Giant ferns First land vertebrates • 340 million years ago • amphibians—toads frogs • lungs  blood flow from heart to lungs • lose water from their skin so must stay moist First reptiles and insects • 300 million years ago • snakes, crocodiles, turtles, lizards • skin watertight, so could live out of water • spiders
  13. 13.  First gymnosperms • 290 million years ago • naked seeds • Evergreen trees First mammal like reptiles • 240 million years ago • 4 chambered heart • milk • fur
  14. 14.  First dinosaurs • 220 million years ago • Dinosaurs dominated in the Jurassic period First birds evolve • 180 million years ago • reptiles found on land, sea and in air • Archeopteryx Flowering plants appear • 120 million years ago • angiosperms Dinosaur extinction • 65 million years ago
  15. 15.  Very early primates • 64 million years ago • Order of mammals that apes, monkeys, and humans belong to. Anthropoids evolve • 35 million years ago • Day active-primates • Animals with five flexible fingers • Monkeys, apes, and humans
  16. 16.  Lucy fossil • 4 million years ago • earliest hominid—common ancestor to humans and apes (gorillas, orangutans, and chimps) • walked upright, small skull, teeth intermediate between humans and apes Homo sapiens • 0.1 million years ago (100,000 years ago) • Human species • Direct ancestor is Homo erectus

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