If the thyroid gland is unable to make thyroid hormone due to an inadequate supply of a micronutrient,a feedback loop causes more TSH to be released by the pituitary gland,which in turn causes the thyroid gland to grow as it attempts to make more thyroid hormone.If the lack of the micronutrient continues,the thyroid gland can grow quite large and is called a goiter.The lack of which micronutrient is most likely to cause a goiter?
A) Fluoride
B) Iodine
C) Chromium
D) Zinc
E) Copper

Question

Quizplus · Accepted Answer

Iodine is required for the production of thyroid hormone. Without adequate iodine, the thyroid gland cannot make enough thyroid hormone and the feedback loop causes the gland to grow in size, resulting in a goiter. Fluoride, chromium, zinc, and copper do not play a direct role in thyroid hormone synthesis.

If the Thyroid Gland Is Unable to Make Thyroid Hormone