1- Name the two hormones commonly referred to as "thyroid hormone" and describe their general actions.
2- Why would an overactive thyroid cause Krista's weight loss, sweating, and elevated heart rate?
3- Krista wonders if TSH is a "thyroid hormone," and Dr. Weisman explains that it is not. State the action of thyroid-stimulating hormone (TSH) and name the gland that secretes it.
4- How is the secretion of TSH regulated under normal conditions?
5- In Graves' disease, the immune system makes antibodies that stimulate TSH receptors on the thyroid gland. What effect does this have on Krista's thyroid?
6- Why is Krista's TSH level low instead of high?
7- If Krista had been diagnosed with hypothyroidism, what would happen to her levels of TSH and thyroid hormone?
8- A common treatment for Graves' disease involves ingesting a dose of radioactive iodine, which slowly destroys the thyroid gland. Why are other tissues unaffected?