1. http://www. hulu. com/watch/63314/origins-of-life
Origin of Life

2. How old is the earth?
The earth itself is said to be 4.6 billion years old.

3. How long has life been on the planet?
Stromalites- ancient phototrophs and heterotrophic bacteria living in colonial associations
Have been discovered in Australia and southern Africa
Dating back between 3.4 and 3.5 billion years old.

4. What were early atmosphere conditions?
It was a reducing atmosphere with:
intense lightning
tremendous volcanic activity
very little oxygen
intense ultraviolet radiation
meteorite bombardment
Some constituents were:
H2O, CO2, CO, CH4 (methane), NH4 (ammonia), N2, H2S (hydrogen sulfide), H2

5. Abiotic Synthesis Theory of Life:
A.I.Oparin (1920's) primitive earth’s atmosphere favored chemical reactions that made simple monomers that eventually formed complex organic compounds necessary for life.
Spontaneous chemical synthesis
Proposed where the first cells came from.
Amino acids  proteins/enzymes  coacervates  single celled organisms

6. Coacervates Tiny spheroid bodies that have somewhat of a membrane.
First seen in the Moscow laboratory of A. I. Oparin
Intake of material, growth, division, & inc. in #
Chemical reactions in them became their metabolism

7. Let’s Test this Hypothesis!
Stanley Miller and Harold Urey (1952)
Tested Oparin’s hypothesis by building an apparatus to simulate the conditions of the earth at that time. 
Their experiments produced 20 amino acids, ATP, lipids, some sugars, and the bases of RNA and DNA.

8. How did these molecules form without the aid of enzymes?
Sidney Fox (University of Miami )
Clay was abundant in prebiotic earth.
Dripped a dilute solution of organic monomers onto hot sand, clay, and rock.
Water vaporized and left behind polypeptides he called proteinoids.
These proteinoids self-assembled into small spheres called protobionts.
These small spheres were capable of osmotic swelling and shrinking and even able to produce a membrane potential.

9. Sydney Fox

10. Was RNA the first Genetic Material?
Leslie E. Orgel produced short polymers of self-replicating RNA abiotically in a test tube without enzymes.
RNA has the ability to act as a catalyst to help make mRNA, tRNA or rRNA
Perhaps captured by the protobionts and the entire structure developed under the guide of natural selection.

11. Other Origin Theories:

12. Deep-Sea Vents
Some researchers believe that life began on the sea floor away from the harsh surface environments. .
The discovery of deep sea vents showed the scientific community that the materials needed for life to begin were present away from the harsh surface.

13. Panspermia
Extraterrestrial organic compounds located on the surface of meteorites -could well have contributed to the pool of material found on prebiotic earth.
Modern meteorites have given up specimens of simple organic compounds such as amino acids.

16. Definite evidence of life on Mars?
Martian Billboard

17. Some Clips http://www.pbs.org/wgbh/nova/origins/