During the telophase stage, the chromosomes uncoil and revert to their extended form, which is manifested in the homogeneous appearance of chromatin displayed by interphase chromosomes. Also in late telophase, the chromosomal fibers disappear and nucleoli develop at the nucleolar organizing sites. Nuclear envelopes start to form around the nuclei from remnants of the parent nuclear envelope and portions of the endomembrane system contained in each of the daughter cells. In addition, the cytoplasmic network of microtubules begins to once again define the cellular structure.