Biology - Topic 1 Biological Molecules - Water

The Chemistry Of Water

-Water is the medium in whch all the reactions take place in living cells. Withoug it, substances could not move around the body. Water is one of the reactants in the process of photosynthesis, on which almost all life depends. And water is a major habitat - it supports more life than any other part of the planet. 

- The importance of water is due to the basic chemistry of its molecules. The simple chemical formula of water is H2O. This tells us that two atoms of hydrogen are joined to one atom of oxygen to make up each water molecule. However, because the electrons are held closer to the oxygen atom than to the hydrogen atoms, water is a polar molecule. 

- One of the most important results of this charge sepeeration is that water molecules form hyrogen bonds. The slightly negative Oxygen atom of one water molecule will attract the slightly positive hydrogen atoms of other water molecules in a weak electrostatic attraction called a hydrogen bond. This means that the molecules of water 'stick together' because many hyrogen bonds are present. Water has a high melting and boiling point and it takes alot of energy to overcome the bonds. Hydrogen bonds are an important concept in biochemistry…