chemistry

BIOLOGICAL IMPORTANCE S-BLOCK ELEMENTS

 Biological importance of Ca and Mg

i) Magnesium ions are concentrated in animal cells and Calcium ions are concentrated in body fluids, outside the cell.

ii) All enzymes that utilize ATP in phosphate transfer require magnesium ion as cofactor.

iii) In green plants magnesium is present in chlorophyll.

iv) Calcium and magnesium ions are also essential for the transmission of impulses along nerve fibres.

v) Calcium ions are important in blood clotting and are required to trigger the contraction of muscles.

vi) Calcium ions also regulate the beating of the heart.

 Biological importance of Na and K

i) Sodium ions participate in the transmission of nerve signals.

ii) Sodium ions also regulate flow of water across the cell membranes and in transport of sugars and amino acids into the cells.

iii) Potassium ions are the most abundant cations within cell fluids, where they activate many enzymes, participate in oxidation of glucose to produce ATP.

iv) Potassium ions in combination with sodium ions are responsible for transmission of nerve signals.

v) The functional features of nerve cells depend upon the sodium potassium ion gradient that is established in the cell.