What mineral is critical to the synthesis of thyroxine?
a. Iron
b. Copper
c. Iodine
d. Magnesium
e. Manganese
Question 2
What is the primary function of the thyroid hormones?
a. Precursors for hemoglobin synthesis
b. Counteract a deficiency of goitrogens
c. Control the rate of oxygen use by cells
d. Regulate acetylcholine concentrations in the central nervous system
e. Stimulation of the production of antibodies in response to antigens