What changes occur in the genes of sex cell

During Telophase 2, a nuclear envelope forms around each set of new chromosomes. In this stage, cytokinesis occurs, which is responsible for producing four daughter cells each with a haploid set of chromosomes. During the crossing-over phase some chromosomes are observed to have segments that have recombined with the original parent chromosomes.   

When the phase is over, the two cells are now finally separated and their nuclear membranes are fully formed causing the meiosis cell division to be completed.