universe formed 15 billion years ago (big bang) galaxies formed from stars, dust and gas earth...
Post on 21-Dec-2015
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TRANSCRIPT
When space turned around, the earth heatedWhen space turned over, the sky reversed
When the sun appeared standing in shadowsTo cause light to make bright the moon,
When the Pleiades are small eyes in the night,From the source in the slime was the earth formedFrom the source in the dark was darkness formed
From the source in the night was night formedFrom the depths of the darkness, darkness so deep
Darkness of day, darkness of nightOf night alone
Did night give birthBorn was Kumulipo in the night, a maleBorn was Po'ele in the night, a female
Born the coral polyp
Born of him a coral colony emerged....
pp. 3-4, Johnson, R.K., 1981. The Kumulipo: Hawaiian hymm of creation. Vol. 1. TopgallantPublishing Co., Ltd., Honolulu, Hawai'i
• Universe formed 15 billion years ago (Big
Bang)
• Galaxies formed from stars, dust and gas
• Earth formed 4.6 billion years ago
• Suns energy stripped away 1st atmosphere
• 2nd atmosphere formed from volcanic outgassing
• Primitive atmosphere: CO2, water vapor, lesser
amts of CO, N2, H2, HCl, and traces of NH3 and
CH4 (3.5 bya)
• O2 came in 1.5 bya from
photosynthesis
• Present atmosphere: 78% N2, 21% O2, 0.04% CO2, + trace gasses
Formation of Earth’s Oceans(4 bybp):
Rain
Condensation
Off gassing of water vapor from volcano
Life began~ 3.5 bya
Organic molecules (C H O N P S) swimming in shallow seas
Stage 1: Abiotic synthesis of organic molecules such as proteins, amino acids and nucleotides
Stage 2: joining of small molecules (monomers) into large molecules
Stage 3: origin of self-replicating molecules that eventually made inheritance possible
Stage 4: packaging these molecules into pre-cells, droplets of molecules with membranes that maintained an internal chemistry
Thomas Huxley- Search for origin of lifeBathybias heckalii- primordial ooze
Wyville Thompson: HMS Challenger (1872-1876) found it was actually diatomacous ooze reacting with seawater and ethyl alcoholAlso, disproved Forbes’ Azoic Theory (1868-1870)
Miller & Urey (1953)- mixed water vapor, NH3, CH4, H2
+ electric spark amino acids and other organic compounds
electrodes
spark
CH4
NH3
H2
water vapor
condenser
boiling water
water containing organic compounds
Produced:• 20 amino acids• Several sugars• Lipids• Purine and pyrimidine bases (found in
DNA, RNA & ATP)
chemosynthetic bacteria (extremophiles)
Chemosynthesis:
02 + 4H2S + C02 CH20 + 4S +3H20
Stromatolites (bacteria & cyanobacteria)
Oldest fossils found in western Australia and southern Africa ~ 3.5 byo
Photosynthesis:
6H2O + 6CO2 + nutrients + light energy C6H12O6 + 6O2
Stromatolites from Shark’s Bay Australia
mostly cyano
Inquiry1. How old is the Earth?2. What was the 1st organism to
have appeared 3.5 bya?3. How did it eat?4. When did oxygen 1st appear in
the atmosphere?5. How was it produced?6. What did Miller & Urey’s study
conclude?