Parathyroid hormone (PTH)
A) increases calcium level in the blood.
B) inhibits the formation of active vitamin D in the kidneys.
C) decreases the rate of bone breakdown.
D) has an effect similar to that of calcitonin.
E) has all of these characteristics.

Question

Quizplus · Accepted Answer

Parathyroid hormone (PTH) increases calcium level in the blood by promoting the release of calcium from bones into the bloodstream and enhancing the reabsorption of calcium by the kidneys. PTH also stimulates the production of active vitamin D in the kidneys, which increases calcium absorption in the intestines. It does not inhibit the formation of active vitamin D in the kidneys or decrease the rate of bone breakdown. PTH has an opposing effect to that of calcitonin, which lowers blood calcium levels.

Parathyroid Hormone (PTH)