Which of the following is CORRECT concerning the actions of calcitonin and parathyroid hormone?
A) Goth calcitonin and parathyroid hormone increase blood calcium levels.
B) Goth calcitonin and parathyroid hormone decrease blood calcium levels.
C) Calcitonin increases and parathyroid hormone decreases blood calcium levels.
D) Calcitonin decreases and parathyroid hormone increases blood calcium levels.
E) Calcitonin decreases blood calcium levels but parathyroid hormone has no effect on calcium.

Question

Quizplus · Accepted Answer

Calcitonin and parathyroid hormone have opposite effects on blood calcium levels. Calcitonin decreases blood calcium levels by inhibiting bone resorption (breakdown of bone) and increasing calcium excretion by the kidneys. In contrast, parathyroid hormone increases blood calcium levels by promoting bone resorption, increasing calcium absorption in the intestines, and reducing calcium excretion by the kidneys. Therefore, option D is correct - calcitonin decreases (so it's the opposite of increasing) and parathyroid hormone increases (so again, it's the opposite of decreasing) blood calcium levels.

Which of the Following Is CORRECT Concerning the Actions of Calcitonin