PATHOLOGY

Detailed explanation-1: -Calcitonin-a hormone from the parathyroid which lowers the calcium-level of the blood. Nature.

Detailed explanation-2: -Calcitonin is a 32 amino acid hormone secreted by the C-cells of the thyroid gland. Calcitonin has been preserved during the transition from ocean-based life to land dwellers and is phylogenetically older than parathyroid hormone.

Detailed explanation-3: -Calcium homeostasis is maintained by actions of hormones that regulate calcium transport in the gut, kidneys, and bone. The 3 primary hormones are parathyroid hormone (PTH) 1, 25-dihydroxyvitamin D-3 (Vitamin D3), and calcitonin.