An organism is any living entity. To better understand this, it may be helpful to learn what three domains (types) of organisms exist. The three domains of organisms are Bacteria, Archaea, and Eukarya. Bacteria Salmonella Photo credit: https://www.eehealth.org/blog/2018/07/salmonella-infection/ Bacteria are the least complex type of organisms. They are prokaryotes, meaning they are unicellular (single-celled) organisms. … Continue reading What Is an Organism?