GENERAL HISTOLOGY

Detailed explanation-1: -Thyroid hormone is the hormone that controls your body’s metabolism, the process in which your body transforms the food you eat into energy. The two main hormones your thyroid releases-thyroxine (T4) and triiodothyronine (T3 )-collectively make up thyroid hormone.

Detailed explanation-2: -Even though both molecules can trigger biological effects, T3 is considered the biologically active thyroid hormone that binds to thyroid hormone receptors (TR), while T4 is a prohormone that must be converted to T3 in order to initiate signalling and gain biological activity.

Detailed explanation-3: -T4 (thyroxine) is the main hormone produced by the thyroid gland. A laboratory test can be done to measure the amount of free T4 in your blood. Free T4 is the thyroxine that is not attached to a protein in the blood.