title: An electronic method for measuring the heart frequency of the waterflea: Daphnia pulex.
mesh_terms: D000818:Animals; D003621:Daphnia / Q000502:physiology*; D004581:Electronics / Q000295:instrumentation*; D006339:Heart Rate / Q000187:drug effects; D008722:Methods; D010634:Phenobarbital / Q000494:pharmacology
chemical_list: D010634:Phenobarbital