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Mr. Hoeldtke
Where did life come from?
3.6 billion years ago
Nitrogen
Water Vapor
CO2
Methane
Hypothesis:
Did not need oxygen to survive
Unicellular organisms
Able to survive extreme environments
Lived in Ocean
Example: Archaebacteria
Plants and microorganisms release oxygen during photosynthesis
Microorganisms create oxygen through similar processes
Allows for the organisms around us to survive
Dinosaurs were huge?
Urey and Miller (1953)
Mixture of Nitrogen, CO2, methane and water vapor
Electricity (lightning)
Ensured that no oxygen or unicellular organisms in mixture
Why?
Found some of the building blocks of life (pre-proteins)
Other scientists had similar experiments that had precursors to nucleic acids and carbs.
Hypothesis: That cells formed gradually over millions of years in earth’s early oceans
Fossils
Preserved remains of organisms under certain conditions
Bacteria-like organisms found that were dated 3.5-3.6 billion years old
Would use chemical energy and have oxygen as a waste product
Eventually, chemical resources depleted
Cells that survived would need another energy source
Photosynthesis
Thanks plants