Electrolytes and ions of the body

Electrolytes are solutions of positively and negatively charged ions and have several different roles within our bodies  

Each of the body fluids differ in their content. The plasma cells contains a number of protein ions (remember amino acids and proteins can form ions and zwitter ions), whereas the fluids between the cells (intercellular fluids) contain fewer protein ions. Plasma moves around inside the blood vessels which are impervious to large protein molecules passing through their membranes into the interstitial fluids. 

All cells, including muscle and nerve cells, have inside them an intracellular fluid (ICF) which contains high levels of potassium, K+, phosphate ions, PC 43+, and protein and small amounts of Na+ ions and chlorine ions. Outside the cells in the extracellular fluid (ECF) consists mostly of sodium ions, Na+, chloride, Cl, and bicarbonate ions, HC03, but no protein, plus low concentrations of potassium ions. The inner layer of the cell membrane is negatively charged relative to the outside. When activity occurs then an ionic pumping action takes place to try to maintain the balance within the cells between the intra and extra flow of sodium and potassium 

90 % of all sodium cations are in fluids outside the cell (ECF) There are fewer Na+ ions inside cell fluids Essential for conduction of electrical impulses for nerves and muscles Crucial for keeping the balance between osmotic pressure in extracellular fluids and water 

The Na+ concentration is controlled by ADH hormone Loss of Na+ by excess perspiration, diarrhoea or sickness results in weakness, dizziness, headache, hypertension etc. (hyponatraemia) 

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