How did chemisty and oceans produce this?

Remember, the chemistry/biology of 4 billion years ago was totally different than it is today. Today, everything is facilitated by Cells :

Properties of Cells Today:

Prokaryotes

• no nucleus
• no organelles
• no compartments
• circular DNA
• size
• contrast with eukaryotes

Eukaryotes-

• nucleus
• organelles

Prokaryotes precede Eukaryotes by approximately 2 billion years.

Making Polymers Today:

• concentration of monomers and enzymes and proteins which act as an energy source
• O and OH are removed (hydration)
• monomers join together to make polymers

4 Billion years ago there were no cells to facilitate this. The available energy sources were

• lightning (Jupiter -- Galileo Results )
• heat
• UV
• solar radiation

All of the above are quite inefficient compared to enzymes

Now we have a multiplying population of bacteria (prokaryotes) that has to eat to survive:

What to eat?

• First feed off other organic molecules via fermentation
• fermentation is very inefficient, releases little energy
• Big problem --> the food supply is running out

EVOLUTIONARY ADVANTAGE: Bacteria that could process plentiful UV light and INorganic molecules will survive

• are most plentiful molecules dissolved in the oceans
• requires least amount of energy to break apart
• early blue green algae therefore metabolized giving off sulfur as a waste product --> stinky anerobic photosynthesis
• Important --> photosynthesis evolved from a need for the bacteria to be able to feed themselves and multiply

---

There is still a problem:

• Not much is available for anerobic processes to use.
• But hey, there is all this that we are floating in so let's do this

  

So, chlorophyll evolves to more complex forms so that it can capture and store enough UV energy to breaking the hydrogen-oxygen bond in water.

Now we have a mechanism to deliver Oxygen to the atmosphere via the aerobic photosynthesis of blue-green algae. But, the oxygen does not initially go into the earth's atmosphere. Instead we have to wait 1.5 -2 billion years to get oxygen into our atmosphere!

Next Page

___________________________________________________________________

The Electronic Universe Project

e-mail: nuts@moo.uoregon.edu