1. First Life

2. Conditions on Early Earth
CO2, methane and other noxious gases in the atmosphere, extreme heat
Methanogens
Thermophiles
Atmosphere is thick
Sun cannot get through
Oceans are olive green
Caustic and uninhabitable

3. Heavy Bombardment Begins
Oceans are vaporized, toxic rain
Four molecules
Carbon
Nitrogen
Hydrogen
oxygen
Amino acids
Miller-Urey Experiment
Pressure Theory

4. Miller-Urey Experiment
H2O vapor, ammonia, methane, and hydrogen gases
Electric current to simulate lightning
Cooled gases, simulated rain, and collected everything in a flask
Analyzed liquid and found amino acids, sugars, and other organic molecules

5. Pressure Theory Comets carried amino acids to earth
The pressure of the comet hitting the earth did not cause all organic molecules to break down
Instead, amino acids formed peptides, which can then form proteins

6. Amino Acids Amino acids form proteins
DNA codes for proteins which allows the functions of the body to be carried out…that fact makes scientists’ think the formation of amino acids/proteins is relevant to the first events that formed life
First life is Archaebacteria, which are extremophilic, like halophiles, methanogens, thermophiles

7. Heavy Bombardment Ceases
The atmosphere begins to clear because there are no longer impacts throwing particles in the air
Microbial life can begin
Life most likely begins in the oceans or hydrothermal vents--protection from the sun
Organisms would be anaerobic
No oxygen available.