According to partial reinforcement extinction effect, the degree of resistance of a behavior towards extinction serves as regulatory factor. The higher the resistance of a behavior to extinction, the longer that the particular behavior occurs once all the reinforcements have been ceased. A behavior that is given more regular and frequent rewards is more likely to be resistant to extinction.
Copying of cellular components and cleaving of cell into two independent cells. If a cell is not fully-grown or does not have an appropriate cellular environment, it can enter G0 where it can stay for as long as it is necessary.