At which stage does the nuclear envelope begin to break into small vesicles?

1. The chromosomes cannot be reached by the spindle while the nucleus is intact. 2. The envelope must therefore go early. 3. During prophase, the first phase, the nuclear envelope starts to dissociate into small vesicles. 4. The membranous organelles such as the Golgi apparatus and endoplasmic reticulum also fragment and disperse toward the periphery. 5. In telophase the reverse happens, as the chromosomes decondense at the poles. _Source: OpenStax Biology for AP(R) Courses (CC BY 4.0), Ch 10 'Cell Reproduction', sections 10.1-10.5_