<prompt> Calcitriol in children is formed in:GlomerulusBowmann capsulePCTDCT  <response>: Ans: C PCT 25-hydroxyvitamin D3 - Calcitriol 1,25-hydroxyvitamin D3 by la- hydroxylase in PCT- AK Jain 5th730; O.P.Ghai 8th112Calcitriol is produced in the cells of the proximal tubule of the nephron in the kidneys by the action of 25-hydroxyvitamin D3 1-alpha-hydroxylase, a mitochondrial oxygenase and an enzyme which catalyzes the hydro.vylation of 25-hydroxycholecal- ciferol caicifediol. The activity of the enzyme is stimulated by PTH. The reaction is an important control point in Ca2 homeostasis- 