The word that would fill this space would be calcium. Calcitonin lowers it, c<span>alcitriol increases it, and </span><span>parathyroid hormones balance it out.
Calcitriol, parathyroid hormone, and calcitonin regulate Calcium status. The main function of calcitriol is to increase the uptake absorption of calcium from the gut.Parathyroid hormone is the most important endocrine regulator of calcium and phosphorus concentration in extracellular fluid. It function is to stimulate osteoclasts to reabsorb bone mineral, liberating calcium into blood. Calcitonin is a hormone that is produced in humans by the parafollicular cells and is involved in helping to regulate levels of calcium and phosphate in the blood,
