In response to high blood calcium levels, the thyroid gland releases a hormone that works to lower blood calcium. This is an example of which endocrine control method?
A) The hypothalamus and pituitary stimulate a peripheral endocrine gland.
B) The nervous system stimulates a gland directly.
C) Changing plasma levels of a substance stimulate a gland directly.

Question

Quizplus · Accepted Answer

The thyroid gland releases calcitonin in response to high blood calcium levels, which is an example of direct stimulation of a gland by changing plasma levels of a substance, in this case, calcium. This mechanism does not involve the hypothalamus, pituitary, or direct stimulation by the nervous system.

In Response to High Blood Calcium Levels, the Thyroid Gland