Which type of goiter (enlarged thyroid) can be reduced by the addition of iodine to the diet?
A) Hyperthyroid goiter, in which thyroxine does not turn off the pituitary's secretion of thyrotropin
B) Hyperthyroid goiter, in which the thyroid is activated by high levels of thyroxine
C) Hypothyroid goiter, involving low functional thyroxine levels and high thyrotropin levels
D) Hypothyroid goiter, involving high functional thyroxine levels and low thyrotropin levels
E) All types of goiter

Question

Quizplus · Accepted Answer

Hypothyroid goiters occur due to low levels of functional thyroxine and high levels of thyrotropin, which is the pituitary hormone that stimulates the thyroid gland to produce more thyroxine. These types of goiters can be reduced by the addition of iodine to the diet, as iodine is an essential component of thyroid hormone. The thyroid gland requires iodine to produce thyroxine, and without adequate iodine, the gland will enlarge in an attempt to produce more hormone. Other types of goiters, such as hyperthyroid goiters, involve different mechanisms and are not typically treated with iodine supplementation.

Which Type of Goiter (Enlarged Thyroid) Can Be Reduced by the Addition