NASC 2: Why is the body mostly made up of water?

Water is of major importance to all living things; in some organisms, up to 90% of their body weight comes from water. Up to 60% of the human adult body is water. According to H.H. Mitchell, Journal of Biological Chemistry 158, the brain and heart are composed of 73% water, and the lungs are about 83% water. The skin contains 64% water, and even the bones are watery: 31%. The chemical structure of water H2O and both the hydrogen and oxygen have great importance as life giving properties and a preserving force to our systems. Women have a higher percentage of adipose tissue than men, giving them a lower percentage of water. Most of the water in the human body is contained inside our cells.

Water In Your Body:  As babies we are approximately 75 to 80% water and as we grow older this percentage decreases until the percentage is reduced to approximately 60 to 65% for men and 50 to 60% for women. 

The ability of water to disassemble and rearrange other molecules is essential to the chemistry of life. It does this by forming weak bonds with the other molecules. This is often why we refer to water as the universal solvent. Water is a perfect conductor of electricity and this becomes important in the day to day operation of our bodies. For example, the electrical potential is shared between the brain neurons through electrochemical transmitters. This electrical potential of brain chemistry must be present for any of our "thoughts" to take place. Water is important to the human body because your body needs to be constantly hydrated. Water helps digest our food so it can provide us with energy, it helps to transport waste out of the body, and it is important in controlling body temperature.

There just wouldn't be any you, me, or Fido the dog without the existence of an ample liquid water supply on Earth. The unique qualities and properties of water are what make it so important and basic to life. The cells in our bodies are full of water. The excellent ability of water to dissolve so many substances allows our cells to use valuable nutrients, minerals, and chemicals in biological processes. The carbohydrates and proteins that our bodies use as food are metabolized and transported by water in the bloodstream. No less important is the ability of water to transport waste material out of our bodies. For all those reasons, water is life.




Sources:
http://www.nestle-waters.com/healthy-hydration/water-body
http://www.chemcraft.net/wbody.html
http://www.ask.com/question/why-is-water-so-important-to-the-human-body
http://ga.water.usgs.gov/edu/propertyyou.html