For 10 points, identify this most common mineral in the human body, a major component of bones.
Abscisic acid triggers an influx of this element in stomatal guard cells, and this element's oxalate and carbonate can form raphides in plants. Parathyroid hormone increases serum concentrations of this element, and the sarcoplasmic reticulum stores and(*) pumps this element in muscle cells. In neurons, activation of voltage-dependent channels for this element stimulates neurotransmitter release. Vitamin D aids intestinal absorption of this element, the deficiency of which is a major cause of osteoporosis. For 10 points, identify this most common mineral in the human body, a major component of bones.
Abscisic acid triggers an influx of this element in stomatal guard cells, and this element's oxalate and carbonate can form raphides in plants.
{Calcium}