Too much calcium in the bloodstream, a condition called hypercalcemia, can be very dangerous. The thyroid gland releases a hormone, calcitonin, when calcium is too high. How does calcitonin lower calcium levels in the blood? A) It reduces osteoclast activity and increases osteoblast activity. B) It increases osteoclast activity and reduces osteoblast activity. C) It reduces both osteoclast and osteoblast activity. D) It increases both osteoclast and osteoblast activity.

Question

Quizplus · Accepted Answer

Calcitonin reduces osteoclast activity, which are cells that break down bone tissue and release calcium into the bloodstream. At the same time, calcitonin increases osteoblast activity, which are cells that build new bone tissue and use up calcium from the bloodstream. This overall process results in a lowering of calcium levels in the bloodstream.

Too Much Calcium in the Bloodstream, a Condition Called hypercalcemia