NURS 6501: MIDTERM EXAM:
Please contact Assignment Samurai for help with NURS 6501: Midterm Exam or any other assignment.
Email: assignmentsamurai@gmail.com
Which of the following statements accurately describes normal thyroid physiology?
Group of answer choices
- T4 measurement is the best single test for thyroid function.
- 80% of T3 is iodinated in the liver and kidney to become T4.
- TSH is typically elevated in hyperthyroidism.
- T4 is 20 times more abundant than T3.
- T4 (thyroxine) is the major hormone produced by the thyroid gland, and it is indeed approximately 20 times more abundant than T3 (triiodothyronine) in the bloodstream. Most of the thyroid hormone secreted from the thyroid gland is in the form of T4. T3 is the more biologically active form, but most T3 is derived from the conversion of T4 in peripheral tissues like the liver and kidneys.
- T4 measurement is the best single test for thyroid function: While T4 levels are important, the best single test to assess thyroid function is typically TSH (thyroid-stimulating hormone). TSH is more sensitive because it reflects the body's feedback mechanism to thyroid hormone levels, making it a more reliable marker of thyroid function.
- 80% of T3 is iodinated in the liver and kidney to become T4: This statement is incorrect because T3 is primarily produced from the conversion of T4 in peripheral tissues, not the other way around. The conversion of T4 to T3 occurs mainly in the liver, kidneys, and other tissues, and involves deiodination (removal of one iodine atom from T4).
- TSH is typically elevated in hyperthyroidism: This statement is incorrect. In hyperthyroidism, where there is an excess of thyroid hormone, TSH is typically low due to negative feedback inhibition. Elevated thyroid hormone levels inhibit the secretion of TSH from the pituitary gland.