Osmosis in Potato Chips

The biological importance of water and its role in living organisms

What is water?

Water (from the Old English word water) is a colourless, tasteless, and odourless substance that is essential to all known forms of life and is known also as the most universal solvent.

Water has a very simple atomic structure, the structure consist of two hydrogen atoms bonded to an oxygen atom, which can also be related to as hydrogen oxide. At least 70% of the mass of living organisms is water, and almost all of chemical reaction of life takes place in an aqueous solution. The other chemical that makes up living things are organic macro molecules that belong to the 4 groups Lipids, proteins, nucleic acids, and carbohydrates. Without water, life on earth would not be possible and we as humans are made from approximately 80% water by mass and some amphibians Jellyfish being a primary example are made up of up to 96% water. Water also provides a place for organism to live in, 75% of the earths surface is also covered by water.

The molecular structure of water

A water molecule is formed by a covalent bond; Covalent bonds are formed by sharing electrons in the outer orbits of the quantum shells. Water molecules are charged with the hydrogen atom being slightly positive and the oxygen slightly negative, this opposite that transpires cause an attraction forming hydrogen bonds in the process. This slight charge that occurs means that when water molecules are close together the positively charge hydrogen bond catch the attention of the slightly negatively charged oxygen atom of another water molecule that forms a weak, long distanced hydrogen bond but, the sheer number of them have significant strength to keep the molecules together.

In this diagram the red lines are covalent bonds that hold oxygen that is represented by red and hydrogen (blue) atoms together in the water molecule.

Water has a number of important properties that is essential in making life possible many of the properties listed below are due to hydrogen bonds in water.

• Solvent