Which of the following statements regarding calcitriol's role in calcium homeostasis is FALSE?
1) calcitriol production in the kidney is stimulated by the parathyroid hormone in response to low blood calcium
2) calcitriol works to increase blood calcium levels
3) when blood calcium levels are low, calcitriol's short term response is to stimulate the resorption of bone
4) calcitriol is the active metabolite of vitamin D made in the kidney, and facilitates calcium absorption in the small intestine
5) tubular reabsorption of calcium kid by