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.
Answer:A
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.