MICROANATOMY

Detailed explanation-1: -Calcitonin is a hormone that your thyroid gland makes and releases to help regulate calcium levels in your blood by decreasing it. Calcitonin opposes the actions of the parathyroid hormone, which is a hormone that increases your blood calcium levels.

Detailed explanation-2: -Calcitonin (CT) secretion by parafollicular cells of the thyroid (C cells) is regulated by small changes in the concentration of extracellular calcium ([Ca2+]e).

Detailed explanation-3: -If the body needs more hormones, T3 and T4 can be released from the proteins in the blood and do their job. The third hormone produced by the thyroid gland is called calcitonin. Calcitonin is made by C-cells. It is involved in calcium and bone metabolism.

Detailed explanation-4: -The thyroid gland produces thyroxine (referred to as T4), which is a relatively inactive prohormone, and the highly active hormone called triiodothyronine (referred to as T3). Collectively, thyroxine and triiodothyronine are referred to as the thyroid hormones.