To prevent the legislative branch from becoming too powerful.
The Nucleus is the control center, or brain of the cell.
The genetic equilibrium represents the condition of a genotype or an allele in the genetic pool of a particular population, where there are no changes in the frequency in the successive generations. This basically means that the population has managed to reach the peak of its evolution for the environment in which it leaves, so there's no evolutionary pressure for changes.
In order for the genetic equilibrium to be maintained for prolonged period of time, the population should not face any evolutionary pressure that will cause changes in it. In essence, this means that the environment in which the population lives should remain exactly the same as it is for longer period of time, so the population will have no need to change its appearance or behavior.
