Water is indispensable for life. What properties of water make it useful for all biological processes on the earth?
a) Water is a polar solvent due to which it is regarded as the ‘universal solvent’ .
b) Water has high specific heat capacity.
c) Water has low viscosity and high surface tension.
d) The density of water decreases below 4◦C.
e) Capillarity of water
Properties of water that makes it useful for all biological processes on the earth are:
(a) All polar substances are known to dissolve in polar solvents like water. All the essential substances in living organisms are solutes dissolved in water and transported from one place to another.
(b) Specific heat is the amount of heat required to increase the temperature of one gram of matter by one degree rise in temperature. Because of having high specific heat, it needs high amount of energy to increase its temperature. This is why living organisms have a constant temperature needed for metabolic processes in the body.
(c) Surface tension is the cohesion of the water molecules on the fluid surface of occupying the least volume. Viscosity is the resistance of a fluid to flowing water.
d) Water expands when its temperature becomes lesser than 4◦C. This decreases its density and making ice float. This helps living organisms to survive in frozen oceans and lakes and the upper frozen layer prevents the whole water to freeze acting as an insulator.
e) Water rises in capillary tubes which is a property that helps transport of water from roots of the plants to other parts of the plant.