Important facts for living things during the precambrian

During the Proterozoic life evolved from simple bacteria having prokaryote cells, first to more complex single celled organisms, the eukaryotes, and then to multi-celled plants and animals. It is also during this time that the earth's atmosphere was transformed by cyanobacteria.

Aneutral atom must have the same number of neutrons and protons? no, they must have the same number of protons and electrons