Carbon-based Life - Characteristics of Carbon As A Basis For Life

Characteristics of Carbon As A Basis For Life

The two most important characteristics of carbon as a basis for the chemistry of life, are that it has four valence bonds and that the energy required to make or break a bond is just at an appropriate level for building molecules which are not only stable, but also reactive. The fact that carbon atoms bond readily to other carbon atoms allows for the building of arbitrarily long complex molecules and polymers.

There are not many other elements which even appear to be promising candidates for supporting life - for example, processes such as metabolism - but the most frequently suggested alternative is silicon. This is in the same group in the Periodic Table of elements and therefore also has four valence bonds. It also bonds to itself, but generally in the form of crystal lattices rather than long chains. Silicon compounds are generally stable but do not support the ability readily to re-combine in different permutations in a manner that would plausibly support lifelike processes.