Thyroglobulin and thyroxine-binding globulin, shortened to TBG, have similar names but work in different places. Thyroglobulin is a very large protein made by thyroid follicular cells...

The names T3 and T4 directly describe iodine count. T3, or triiodothyronine, contains three iodine atoms; T4, or thyroxine, contains four. Inside the thyroid, iodinated tyrosine...