ANATOMY

Detailed explanation-1: -Thyroxine is the main hormone secreted into the bloodstream by the thyroid gland. It plays vital roles in digestion, heart and muscle function, brain development and maintenance of bones.

Detailed explanation-2: -The thyroid gland releases triiodothyronine (T3) and thyroxine (T4). These hormones play an important role in regulation of your weight, energy levels, internal temperature, skin, hair, nail growth, metabolism and is an important part of the endocrine system.

Detailed explanation-3: -Metabolism: thyroid hormone increases the basal metabolic rate. It increases the gene expression of Na+/K+ ATPase in different tissues leading to increased oxygen consumption, respiration rate, and body temperature.

Detailed explanation-4: -Thyroxine had a subtle effect on resting metabolic rate, increasing it by 4% (p = 0.059) without a change in resting ATP demand (i.e., ATP flux) of the vastus lateralis.

Detailed explanation-5: -Once your thyroid releases thyroxine (T4) into your bloodstream, certain cells in your body transform it into triiodothyronine (T3) through a process called de-iodination. This is because cells that have receptors that receive the effect of thyroid hormone are better able to use T3 than T4.