Kalsíumjónum
Kalsíumjónum is the Icelandic term for calcium ions. A calcium ion, represented by the chemical symbol Ca²⁺, is an atom of calcium that has lost two electrons, resulting in a net positive electrical charge. Calcium is a divalent cation, meaning it carries a +2 charge. In biological systems, calcium ions are essential for a wide range of cellular and physiological processes. They play a critical role in muscle contraction, nerve impulse transmission, blood clotting, and the maintenance of bone structure. The concentration of calcium ions within cells and in extracellular fluids is tightly regulated by various transport mechanisms and signaling pathways. In the human body, the majority of calcium is stored in bones and teeth, providing structural support. However, the small fraction of calcium ions circulating in the blood and extracellular fluid is vital for immediate physiological functions. Imbalances in calcium ion levels, known as hypocalcemia (low calcium) or hypercalcemia (high calcium), can lead to significant health problems affecting the nervous system, heart, and muscles.