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What is Vitamin D is synthesized by? and explain in detail?
The keratinocytes of the skin are unique in being not only the primary source of vitamin D for the body, but in possessing the enzymatic machinery to metabolize vitamin D to its active metabolite 1,25 dihydroxy vitamin D. Fuhermore, these cells also express the vitamin D receptor (VDR) that enables them to respond to the 1,25(OH)2D they produce.