I know we have probably discussed this or I may have read over it and just forgot, but the remnants of the nuclear envelope stay in the cell correct? And then it also grows during anaphase and telophase so that it can surround the chromosomes in both the new cells in cytokinesis?

What would happen to the strands of DNA and the chromosomes if an error were to occur during one of the stages of Interphase? Would it be just a mutation like we learned about in Biological Concepts or something more complex?