BIOLOGICAL IMPORTANCE OF MAGNESIUM & CALCIUM

1. An adult body contains about 25g of Magnesium and 1200 g of calcium as compared with only 5g of iron and 0.06g of copper. The daily requirement in the human body has been estimated to be 200-300 mg.

2. All enzymes that utilize ATP in phosphate transfer require magnesium as the cofactor.

3. The main pigment for the absorption of light in plants for photosynthesis is green coloured chlorophyll which contains magnesium.

4. 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. The calcium concentration in plasma is regulated at about 100 mg L-1. It is maintained by two hormones.

5. Calcitonin and parathyroid hormone. Bone is not an inert and unchanging substance but is continuously being solubilized and redeposited to the extent of 400 mg per day in man. All the calcium passes through the plasma.

Related Topic Name

1. Group I elements : Alkali metals
2. Characteristics of compounds of alkali metals
3. Anomalous properties of lithium
4. Some important compounds of sodium
5. Biological importance of sodium and potassium
6. Group II elements : Alkaline earth metals
7. General characteristics of the compounds of the alkaline earth metals
8. Anomalous properties of beryllium
9. Some important compounds of calcium