vitamin d defined in 1951 yearvitamin d - vitamin d;
vitamin d - Required as a vitamin by man, though some is synthesized; and by other vertebrates. Fat soluble. Stored in liver. Deficiency in childhood causes rickets; in adults, sometimes osteomalacia. Effect of the vitamin is on absorption and deposition of calcium and phosphate. Synthesis in man is by action of ultraviolet (in sunlight) on a precursor in skin. Several slightly different compounds have Vitamin D activity for man, though only one has for fowls. All are sterols.
near vitamin d in Knolik
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