This thesis explores the question of why life can not be revived when death occurs due to lack of resources. For example, why can't something as simple as E.coli be revived after its death? The hypothesis is that death is not defined by the end of metabolism itself, but rather a continued metabolism which in turn destructs the entity itself. Consequently, a virus should not be capable of ”dying” due to its lack of metabolism. To study self replication, a recent mathematical model utilising Gillespie's algorithm and differential equations has been explored. Using this model, real systems such as the Formose reaction can be modeled. Furthermore, an analytical analysis has been carried out in order to study what impact a side reaction will have on a self replicating system's total growth rate. The result of the analysis states that the growth rate of a self replicating system peaks when all the reactions have the same reaction rate, and declines as the reaction rate of a side reaction increases. In conclusion, a self replicating system that either contains a side reaction or is coupled with another self replicating system can suffer an irreversible death. The reason for this is the metabolism that occurs when the resources have been depleted. At this point, other reactions not belonging to the main metabolism can destroy the self replication. This argument strengthens the hypothesis that a virus does not die in the same way as a living cell, as it does not have a metabolism of its own.