How do the following differ from each other? Thyroid hormones, tetraiodothyronine, thyroxine, levothyroxine, l-thyroxine, T4, triiodothyronine, liothyronine, T3. The term “thyroid hormone” refers to both the secretory product of the thyroid gland and the active hormone into which it is converted. That is, it includes tetraiodothyronine or thyroxine, same thing, which is secreted by the thyroid…