− | The skin is a producer of '''vitamin D''', the precursor of the hormone, [[Calcium#Calcitriol (Active Vitamin D3)|calcitriol]]. Ultraviolet light at a wavelength of 300nm is required to convert ''7-dehydrocholesterol'' to Vitamin D. Whilst this is a key source of the vitamin in humans, as many animal species have hair covered skin, Vitamin D from this region is usually minimal, with dietary sources being much more important. Vitamin D is then hydroxylated into it's active form, [[Calcium#Calcitriol (Active Vitamin D3)|calcitriol]] in the [[Kidney Endocrine Function - Anatomy & Physiology|kidney.]] | + | The skin is a producer of '''vitamin D''', the precursor of the hormone, [[Calcium#Calcitriol (Active Vitamin D3)|calcitriol]]. Ultraviolet light at a wavelength of 300nm is required to convert ''7-dehydrocholesterol'' to Vitamin D. Whilst this is a key source of the vitamin in humans, as many animal species have hair covered skin, Vitamin D from this region is usually minimal, with dietary sources being much more important. Vitamin D is then hydroxylated into its active form, [[Calcium#Calcitriol (Active Vitamin D3)|calcitriol]] in the [[Kidney Endocrine Function - Anatomy & Physiology|kidney.]] |