what kingdoms are included in each of the three domains in the modern tree of life?
By Regina Bailey. Organisms are classified into three Domains and into one of six Kingdoms of life. These Kingdoms are Archaebacteria, Eubacteria, Protista, Fungi, Plantae, and Animalia. Organisms are placed into these categories based on similarities or common characteristics. Some of the characteristics that are used to determine placement are cell type, metabolism, and reproduction. Below is a list of the six Kingdoms of life and information on a few organisms in each category.