JIPMER 2011
- Exam
- JIPMER
- Year
- 2011
- Subject
- Botany
- Chapter
- Cell Cycle and Cell Division
JIPMER 2011 · Botany · Cell Cycle and Cell Division
Which one of the following precedes re-formation of the nuclear...
Which one of the following precedes re-formation of the nuclear envelope during M-phase of the cell cycle?
Options
- ADecondensation from chromosome and reassembly of the nuclear lamina
- BTranscription from chromosome and reassembly of the nuclear lamina
- CFormation of the contractile ring and formation of the phragmoplast
- DFormaltion of the contractile ring and transcription from chromosomes
Correct answer
A. Decondensation from chromosome and reassembly of the nuclear lamina
Step-by-step solution
At telophase stage, nuclear membrane vesicles associate with the surface of individual chromosomes and fuse to reform the nuclear membranes, which partially enclose clusters of chromosomes before coalescing to reform the complete nuclear envelope. During this process, the nuclear pores reassemble and (the dephosphorylated reassociate to form the nuclear lamina.) One of the lamina proteins (lamina-B) remains with the nuclear membrane fragments throughout mitosis and may help nucleate ressembly. After the nucleus reforms, the pores pump in nuclear proteins, the chromosome decondense and RNA synthesis resumes, causing the nucleolus to reappear.