Bacteria are single called organisms that does not have a nucleus and need only a nutrition source on a surface (organic matter/dirt) to allow it to colonize and live in groups either outside the body or in it. read more
• Protozoa is a subkingdom of the protista. • Protista Kingdom includes plant like Phytotrophs, animal like prtotozoa, and fungus like slime moulds, whereas protozoa only has animal like unicellular or multicellular organism. read more
Difference: Bacteria are single celled and prokaryotic organisms. They replicate in an asexual manner. They can be harmful as well as beneficial; it depends upon the type of bacteria. read more