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D vitamin

A family of lipo-soluble steroids important to the absorption, metabolism, and function of calcium and phosphorus and the growth and development of bone and tooth enamel. Found naturally in animal tissues, cholecalciferol (vitamin D3) is formed in the skin when ultraviolet light activates cholesterol conversion into vitamin D3. Ultraviolet irradiation of ergosterol (plant vitamin D) forms ergocalciferol (vitamin D2).
Synonym:vitamin D compound
vitamin-D
Chemical structure:3-[2-[7a-methyl-1-(1,4,5-trimethylhex-2-enyl)-1,2,3,3a,5,6,7,7a-octahydroinden-4-ylidene]ethylidene]-4-methylidene-cyclohexan-1-ol
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