title: Endosymbionts, biogenic amines, and a heterodyne hypothesis for circadian rhythms.
mesh_terms: D001679:Biogenic Amines / Q000378:metabolism*; D001683:Biological Clocks; D002477:Cells / Q000378:metabolism; D002940:Circadian Rhythm; D005057:Eukaryotic Cells / Q000378:metabolism; D013559:Symbiosis
chemical_list: D001679:Biogenic Amines