title: Comments on the role of the cyst in the life cycle and survival of free-living protozoa.
mesh_terms: D000220:Adaptation, Biological; D000818:Animals; D002473:Cell Wall / Q000648:ultrastructure; D004463:Ecology; D056890:Eukaryota / Q000254:growth & development* / Q000648:ultrastructure; D012621:Seasons