Human phosphate homeostasis is regulated at the level of intestinal absorption of
phosphate from the diet, release of phosphate through bone resorption, and renal
phosphate excretion, and involves the actions of parathyroid hormone, 1, 25-dihydroxy-
vitamin D, and fibroblast growth factor 23 to maintain circulating phosphate levels within a
narrow normal range, which is essential for numerous cellular functions, for the growth of
tissues and for bone mineralization. Prokaryotic and single cellular eukaryotic organisms …