Why is Water such an important substance in biology

Authors Avatar

Why is Water such an important substance in biology?

Water plays a major role in all living things. It makes up between 65 and 95% by mass of most plants and animals. About 80% of an individual human cell is water.

        Water has a simple molecular structure. It is composed of one oxygen atom and two hydrogen atoms. Each hydrogen atom is covalently bonded to the oxygen, by a pair of shared electrons. Thus there are 4 pairs of electrons surrounding the oxygen atom, two pairs involved in covalent bonds with hydrogen, and two unshared pairs on the opposite side of the oxygen atom. Oxygen is an ‘electronegative’ or electron ‘loving’ atom compared with hydrogen.

Join now!

Water is a polar molecule, meaning that there is an uneven distribution of electron density. Water has a partial negative charge (δ-) near the oxygen atom due to the unshared pairs of electrons and partial positive charge (δ+) near the hydrogen atoms.

The shape of the water molecule is triangular rather than linear; the angle between the nuclei of the atoms is approximately 105˚.

In theory, water should be a gas, but, at room temperature, it is a liquid. The hydrogen bonds in water hold the molecules together, causing it to be liquid.

        Water has a high ...

This is a preview of the whole essay