Basic principles of normal development

In other brain regions such as the cerebellum, there are cells simultaneously undergoing proliferation, differentiation, migration, and apoptosis. Thus, the contribution of these basic cellular processes to organ development can vary temporally across organ regions and in relation to each other. 

The interactions between cells involved in these critical processes for organ development are of great importance and make them susceptible to perturbations by outside influences. Characteristics of these interactions include the need for sufficient populations of cells in proximity to each other and the need for sufficient 

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