Explain the significance of sodium, potassium, magnesium and calcium in biological fluids.

Significance of sodium:

⇒ Sodium ions are found primarily on the outside of cells, being located in blood plasma and in the interstitial fluid which surrounds the cells.

⇒ The ions participate in the transmission of nerve signals, in regulating the flow of water across cell membranes and in the transport of sugars and amino acids into cells.

Significance of potassium:

⇒ Potassium ions within the cells activate the enzymes and participate in the oxidation of glucose to produce ATP.

⇒ It combines with sodium and are responsible for the transmission of nerve signals.

Significance of magnesium:

⇒ Magnesium is required as the cofactor in all the enzymes that utilise ATP in phosphate transfer.

⇒ Magnesium is the main pigment for the adsorption of light in plants.

Significance of calcium:

⇒ About 99 % of body, calcium is present in bones and teeth.

⇒ It also plays important roles in neuromuscular function, interneuronal transmission, cell membrane integrity and blood coagulation.