1. Please take out Breeding Bunnies Lab to turn in
Take out a half sheet of paper for a warm up
Have your notebook turned to page 106 for the notes for today: Origin of Life

2. Brain Checkpoint 1. How many lobes are in the Cerebrum
2. What are the three major parts of the brain
3. What lobe is structure C? A B C

3. Origin of Life
Page 106
Just write the red lettering into your notebook.

4. Origin of the Earth Universe formed 15 billion years ago (Big Bang)
Galaxies formed from stars, dust and gas
Earth formed 4.6 billion years ago

5. Origin of the Atmosphere
Suns energy stripped away 1st atmosphere
2nd atmosphere formed from volcanic outgassing
Primitive atmosphere: Mostly CO2, water vapor, No Oxygen, very hot, lots of lightening
lesser amounts of CO, N2, H2, HCl, and traces of NH3 and CH4 (3.5 bya)

8. Formation of Earth’s Oceans
Oceans formed from off
gassing of water vapor from volcanoes and meteorites with ice.
Condensation
Rain
Early in Earth’s history, widespread volcanic activity released large amounts of water vapor (H2O vapor) and smaller quantities of other gases. As Earth cooled, the water vapor (a) condensed into clouds and (b) fell to Earth’s surface, where it accumulated to form the oceans (c).

9. Origin of the Atmosphere
O2 came in 1.5 bya from photosynthesis
Present atmosphere: 78% N2, 21% O2, 0.04% CO2, + trace gasses

10. Origin of Life
Miller & Urey (1953)- Organic Molecule Theory - 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

11. Origin of Life Produced: 20 amino acids Several sugars Lipids
Purine and pyrimidine bases (found in DNA, RNA & ATP)

12. Origin of Life
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

13. Origin of Life
Stage 2: joining of small molecules (monomers) into large molecules

14. Origin of Life
Stage 3: origin of self-replicating molecules that eventually made inheritance possible

15. Origin of Life
Stage 4: packaging these molecules into pre-cells, droplets of molecules with membranes that maintained an internal chemistry

16. Hydrothermal Vent Theory
At the bottom of the ocean, chimneys of very hot material under immense pressure combined to make inorganic material that then formed into macromolecules and then life.

17. Meteorite Theory – Rocks containing bacteria and other organic molecules survived impact and seeded the planet with life.

18. Endosymbiotic Theory Endo= inside Symbiotic=mutually beneficial
Idea that mitochondria and chloroplasts came from engulfing prokaryotic cells