The release of parathyroid hormone is controlled by
A) thyroid hormone.
B) TSH.
C) the hypothalamus.
D) blood calcium levels.
E) all of the above

Question

Quizplus · Accepted Answer

The release of parathyroid hormone is primarily controlled by blood calcium levels. As calcium levels decrease, there is an increase in the release of parathyroid hormone from the parathyroid gland, which in turn increases calcium levels in the blood through various mechanisms. Thyroid hormone and TSH do not have a direct effect on the release of parathyroid hormone. The hypothalamus may indirectly regulate calcium levels through its control of the pituitary gland and the release of growth hormone and other hormones, but it is not a direct regulator of parathyroid hormone. Therefore, option D is the best choice.

The Release of Parathyroid Hormone Is Controlled by