Increased levels of the hormone will lead to increased levels of calcium ion in the blood.

3 Chemicals increase blood calcium levels to normal.                                           1. 25 - Dihydroxycholecalciferol                                                                             2. Parathyroid (PTH)                                                                                             3. Calcitonin                                                                                                                                                                                                                                          It's (PTH)
 

Might need you in a few weeks c:

Processes above and be sure to mention the movement of electrons and energy as the carbon atom moves from one reaction to another.