WATER IN LIFE
Water is the major
constituent of living matter. From 50 to 90 per cent of the weight
of living organisms is water. Protoplasm, the basic material of
living cells, consists of a solution in water of fats,
carbohydrates, proteins, salts, and similar chemicals. Water acts
as a solvent, transporting, combining, and chemically breaking
down these substances. Blood in animals and sap in plants consist
largely of water and serve to transport food and remove waste
material. Water also plays a key role in the metabolic breakdown
of such essential molecules as proteins and carbohydrates. This
process, called hydrolysis, goes on continually in living cells.
"Water,"
