What happens to most of the secreted T4?
A) it is phagocytized by target tissues.
B) it is converted into T3 after being peripherally stripped of one of its I atoms.
C) it is the major biologically active form of thyroid hormone at the cellular level.
D) it is split to form two DIT molecules, which are excreted in the urine.
E) it is permitted to exert its full biological effect as a result of epinephrine's permissive actions.

Question

Quizplus · Accepted Answer

Most of the secreted T4 is converted into T3 after being peripherally stripped of one of its I atoms by the enzyme 5'-deiodinase in target tissues, which is responsible for the majority of thyroid hormone action at the cellular level.

What Happens to Most of the Secreted T4