Ca2+
Quick Summary
The calcium ion, symbolized as Ca2+, is a crucial element within living cells and the human body. While approximately 99% of the body's calcium is stored in bones and teeth for structural support, the remaining 1% circulating in the bloodstream plays vital roles. This circulating calcium is essential for muscle contraction, including the heart, nerve impulse transmission, blood clotting, and hormone secretion.12
Cells actively maintain a low concentration of Ca2+ in their cytoplasm, often using calcium pumps to expel excess ions. This ion also functions as a second messenger, transmitting signals within cells, particularly important for rapid responses in neurons and muscle cells. Maintaining a proper calcium balance is critical, with hormones like parathyroid hormone and vitamin D regulating its levels in the blood and bone. Deficiencies can lead to conditions like rickets or osteoporosis.3142
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