Minerals are not very abundant in living organisms, accounting for about 1 to 1.5%, and are generally present as ions. However, they have an important role in supporting life activities.
1. It is one of the raw materials that make up cells. For instance, phosphor is the composition of cell membrane, RNA and DNA; iron is one of the building block of cytochromes and hemoglobin; magnesium is the composition of chlorophyll.
2. It regulates cellular osmotic pressure and pH. The greater concentration of mineral, the higher osmotic pressure, and vice versa. For example, Na⁺ maintains the osmotic pressure of extracellular fluid; K⁺ maintains intracellular osmotic pressure; HCO₃⁺ and H₂PO₄⁺ are blood pH buffers which can maintain pH stable.
3. It is involved in the metabolism of living organisms. Many inorganic ions are one of the components of enzymes, hormones or vitamins, or activators and inhibitors of enzymes. Magnesium ion is the activator of many enzymes. If the concentration of calcium ions is too low in the blood, convulsions will occur. They are also very important for stopping bleeding. If there is a lack of calcium ions, it is difficult for blood to form clots around the wound, resulting in a bleeding wound.