Final answer:
Vitamin D, also known as calcitriol or 1,25-dihydroxycholecalciferol, raises the blood calcium level. It is synthesized in the skin when exposed to UV radiation and undergoes a series of conversions in the liver and kidneys to become the active form of vitamin D. Calcitriol is important for the absorption and reabsorption of calcium in the body.
Step-by-step explanation:
Calcitriol, also known as 1,25-dihydroxycholecalciferol, raises the blood calcium level. When the skin is exposed to UV radiation, a form of vitamin D called cholecalciferol is synthesized. It then undergoes a series of conversions in the liver and kidneys to become calcitriol, the active form of vitamin D. Calcitriol plays a crucial role in the absorption of calcium in the digestive tract, its reabsorption in the kidneys, and the maintenance of normal serum concentrations of calcium and phosphate.