How planet Earth turned green

http://environment.newscientist.com/channel/earth/mg19225804.800-how-planet-earth-turned-green.html

Summary: Earth was covered in thick sheets of ice 2.3 billion years ago. Earth thawed and it released strong oxidants into the oceans and atmosphere for the first time. This set off a chain of events that led to oxygen-tolerant marine organisms and photosynthesis as we know it today.


What is the chemical equation for photosynthesis? CO2 + 2H2O >> CH2O + O2 + H2O.

What organelles are involved in this process? The chloroplast

List three things you learned from this article in your own words.
1.) The Earth was once covered in ice.
2.) Oxygen was once deadly on earth.
3.) Oxygenic photosynthesis involves freeing electrons from water which takes more energy and produces oxygen.

What impact would the absence of this process have on the biosphere? we would be able to survive