Osmotic and ionic regulation.
D000663:Amphibians / Q000502:physiology; D000818:Animals; D000845:Annelida / Q000502:physiology; D001097:Arachnida / Q000502:physiology; D001693:Biological Transport, Active / Q000502:physiology; D001717:Birds / Q000502:physiology; D003445:Crustacea / Q000502:physiology; D056890:Eukaryota / Q000502:physiology; D005399:Fishes / Q000502:physiology; D007313:Insecta / Q000502:physiology; D007448:Invertebrates / Q000502:physiology; D008322:Mammals / Q000502:physiology; D008974:Mollusca / Q000502:physiology; D009995:Osmosis; D009997:Osmotic Pressure; D012104:Reptiles / Q000502:physiology; D014882:Water-Electrolyte Balance / Q000502:physiology*