∞ generated and posted on 2016.02.16 ∞
Obsolete and polyphyletic taxon of eukaryotic organisms excluding animals, plants, and fungi.
Kingdom Protista in particular includes the protozoa and algae, i.e., the protists. See also Five-Kingdom System or organism classification as well Six-Kingdom System.
Figure legend: Various euglena, which are flagellates and often photosynthetic. Image is of stained, fixed specimens.
Note that a monophyletic taxon, that is, true clade that included the protists would by necessity have to include all of the eukaryotes. Indeed, one can quite readily describe kingdom Protista as paraphyletic with, in particular, the animals, plants, and fungi serving essentially as derived protists, that is, protist descendants that no longer look much like protists so no longer are classified as protists.
This is just as birds are descendants of reptiles but typically not classified as reptiles, or as tetrapods basically are modified fish but not usually classified as fish.