Evolution

Protobionts are aggregated forms of different types of molecules, formed abiotically in the primitive sea. These, are considered first cells, produced on the earth because they have an internal environment differ from their surrounding and also exhibit some signs of life such as metabolism and excitibility. Protozoa is a group of unicellular, Prokaryotic, generally heterotrophic organisms. Metazoa includes eukaryotic, multicellular, heterotrophic or autotrophic organisms.