- The Kingdom Monera is a biological kingdom composed of prokaryotic organisms, which are single-celled organisms that lack a membrane- bound nucleus and other membrane-bound organelles. - This kingdom traditionally included all bacteria. In modern classification systems (like the three-domain system), Monera is split into two domains: Archaea (Archaebacteria) and Bacteria (Eubacteria). However, in the older five-kingdom system (Whittaker's classification), Monera encompassed both groups. - Euglenoids and Protozoans belong to the Kingdom Protista (unicellular eukaryotes). - Fungi, Phycomycetes, Basidiomycetes, and Deuteromycetes belong to the Kingdom Fungi (multicellular or unicellular eukaryotes, heterotrophic).