(i) Ca2+ is necessary for the activation of clotting enzymes in plasma,
(ii) Ca2+ controls membrane excitation, and Ca2+influx occurs during the excitatory process of nerve and muscle,
(iii) Ca2+ is bound to cell surfaces and has a role in the stabilization of the membrane and intercellular adhesion,
(iv) Ca2+ is necessary for muscle contraction,
(v) Ca2+ is essential in all excitation-secretion processes, both endocrine and exocrine. It also is essential for neurotransmitter release,
(vi) Ca2+ is necessary for the production of milk and the formation of bone and teeth,
(vii) Ca2+ acts as a second messenger in the cytosol,
(viii) Ca2+ has an essential role in the mineralization of bone.