in the metaphase chromosomes of the cleaving embryos ag-nors adequately reflected the transcriptional activity of the ribosomal genes , whereas in pronuclei of the 1-cell stage embryos argentophilic proteins were not involved in this process , but are likely to play a part in the formation and maturation of pronucleoli , and in the cell cycle regulation .
C0025564
metaphase
C0007634
cell