Calcium is also found in the nervous system, muscles, and the blood where it is integral in proper membrane function, conducting nerve impulses, regulating muscle contractions, and blood clotting.
Calcium is a major component of the skeletal system. It is found in bones and teeth.
Calcium is a metal. It readily oxidizes in air. Because it makes up such a large part of the skeleton, about one-third of the mass of human body comes from calcium, after water has been removed.
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