Water is a very important transport medium for living organisms because of its solvent properties and because it remains a liquid over a large range of temperatures. The cohesion (stickiness) between water molecules means that a very tall thin column of water can be supported before it breaks. Water's extensive capability to dissolve a variety of molecules has earned it the designation of “universal solvent,” and it is this ability that makes water such an invaluable life-sustaining force. On a biological level, water's role as a solvent helps cells transport and use substances like oxygen or nutrients.
