Sodium and potassium cations play a very important role in biological fluids. They are present in biological fluids and the ratio of K to Na is 7:1 in mammals such as human beings, rats, horses. These cations accummulate in cells and create a concentration gradient and potential in the membrane. 1 Magnesium is a part of chlorophyll the green colouring matter of plants. Photosynthesis takes place only in the presence of chlorophyll.
Calcium is present in the form of calcium phosphate Ca3(P04)2 in bone. Ca and Mg play a key role in formation of phosphorus oxygen linkages in biological systems for storage of energy. The pyrophosphate hydrolysis which releases energy is controlled by calcium ions. These ions perform important biological functions such as maintenance of ion balance and nerve impulse conduction.