Which of the following forms of thyroxine would be the least available to tissue receptors?

Question

Quizplus · Accepted Answer

Binding of thyroid hormones and steroid hormones to albumin and prealbumin is weak, with an affinity constant that is much lower than that of the tissue receptor.The hormones bound to albumin and prealbumin are a weakly bound form of free hormones and are considered to be readily bioavailable to tissues.Hormones that are bound to specific transport proteins, in this case thyroxine bound to thyroxine-binding globulin, are held much tighter during transport through the circulation and are thus much less readily bioavailable for release to tissues.

Which of the Following Forms of Thyroxine Would Be the Least