Biology 12 question...please help!?!?

A radioisotope would likely be tagged (show up) in both calcium absorbing cells, but if the isotopes were tagged on Calcium then they would be seen in the Intestine if it was the intestinal cells having the difficulty absorbing (they would be there because they wouldn't be absorbed). If it was the bone cell, it would be either in the blood stream or distributed in the bone spaces (since osteoporosis makes bones spongy like), but not in the bones themselves, since they would have trouble absorbing.