About 2.2 billion years ago, a significant amount of oxygen appeared in the atmosphere. How does this relate to life on Earth during this time and after?
Cyno-bacteria used sun, water and carbon dioxide to produce oxygen
Explanation:
A significant amount of oxygen contributed to the formation of the ozone and protected life form the UV rays. Photosynthesis was successfully and plants were able to convert the light energy from the sun and used for the primary producers an oxygen was a significant by-product.
