Water Vital to Life

Water: Vital to Life

As technology becomes more advanced humans are able to discover, document and go to places that the human race has never been able to before. One of those places is space. Although we know very little compared to the vastness of space, scientists along with other scholars are always finding answers to questions. One of the questions that intrigues many the most “Is there other life forms in the universe besides us?” Biologists who look for life in the universe are known as astrobiologists, astrobiologists instead of looking for other life forms directly they focus on finding planets that contain water. They hope to find water in other planets because water is the substance that allows for life here on earth. Water accounts for 75% of our planet, most cells are surrounded by water and cells themselves consist of 70-95% water. Water is so crucial to the sustainability of life because of its four emergent properties which are its cohesive behavior, ability to moderate temperature, expansion upon freezing and versatility as a solvent.

The first emergent property of water is its cohesive behavior. Water molecules stay together by a large amount of hydrogen bonds which are constantly breaking and creating new bonds. Overall the behavior of the hydrogen bonds that hold the substance together, are defined as cohesive. This cohesiveness in water allows the transport of water and dissolved nutrients against gravity in plants, trees etc. Adhesion also plays a role which is the clinging of one substance to another. Even the tallest tree is able to get water up to its tallest branch because water molecules attach to the insides of the tree (adhesion) and the water molecules also attach to one another (cohesion) and are pulled in an upward motion from the roots due to the evaporation taking place in the leaves. If it wasn’t for water’s cohesive behavior we wouldn’t have trees or plants, and if we don’t have trees we lose a vital source of oxygen, storage of carbon and life on earth.

The second emergent property of water is its ability to moderate temperature. Water can moderate temperature due to its relatively high specific heat. The specific heat of anything is the amount of heat that must be absorbed or lost for 1g of that substance to change its temperature by 1 degree celsius. Due to the high specific heat of water compared to other materials, water will not easily change its temperature because it absorbs or loses a given amount of heat. The most essential part of this property to life on this planet is that a large body of water like an ocean or lake is able to take and store a large amount of heat from the sun or any other source with little change to its own temperature. Not only does this help moderate climates of coastal cities but it also stabilizes ocean temperatures protecting marine life. The water that is on earth moderates the temperature on land and in oceans, lakes etc. keeping it at a point where life is possible here on earth. If water did not have this property and could not absorb heat then the temperature in locations around the world that are near coasts or other large bodies of water would feel the temperature increase drastically. Killing off any organism that surrounds it.

Water is one of the few substances that is less dense as a solid than it is in a liquid state , this is due to its unique trait when becoming a solid its molecules expand instead of contract like most substances when they freeze. This makes ice float on top of liquid water instead of sinking. If water in its solid state would sink, then eventually all ponds, lakes and oceans would freeze solid, making life on Earth impossible. If this would happen then all marine life would cease to exist, their environment would completely freeze from the surface to the depth of the bodies of water. This would wipe out dozens of unique marine life, fishermen would have nowhere to fish and the supply of fish would become scarce. Up north in the United States along with other regions of the world where the temperature drops