. "parasite's" . "single-celled species" . . . . . . "one-celled organisms" . . "pellicle" . . "Protozoan" . "Protozoa" . . . . . . "animal-like unicellular organisms" . "single-celled eukaryotes" . "protozoans" . "protozoon" . "Protozoans" . . "phagotrophic protozoans" . "animalcule" . "single-celled microorganisms" . "single-celled organisms" . . "Protozoa" . "single-celled microorganism" . "Kingdom Protista" . . "protozoan bacteria" . "unicellular metazoa" . "why the kingdom Protista was adopted" . . "one cell organisms" . . . "protists" . . "protozoic" . . "Protozoa#Walls,_pellicles,_scales,_and_skeletons" . "protozoa" . . "protozoan" . . . . "unicellular organisms" . .