Vitamin D3,(S,Z)-3-((E)-2-((1R,3aS,7aR)-7a-methyl-1-((R)-6-methylheptan-2-yl)hexahydro-1H-inden-4(2H)-ylidene)ethylidene)-4-methylenecyclohexanol,"The vitamin that mediates intestinal calcium absorbtion, bone calcium metabolism and probably, muscle activity. Occurs in and is isolated from fish liver oils. Vitamin D acts through a receptor that is a member of the ligand-dependent transcription factor",Cholecalciferol