Respuesta :

onnagodsey

Answer:

Explanation:

Oxygen is of no use to them, so they release it into the air. So there's a simple explanation for the Great Oxidation Event. It was the cyanobacteria, pumping out unwanted oxygen, that transformed Earth's atmosphere.

SaraMHeheez

Answer:

cyanobacteria

Explanation:

using sunshine carbon dioxide and water to produce the carbohydrates