1.   The modified homologous chromosomes separate and move to opposite poles where new nuclei form, each with the haploid number of chromosomes.

2.   A major problem was that when two atomic nuclei collide, they often combine energies to such high levels that the new composite nucleus instantly shakes itself apart.

3.   Heavier elements formed later inside stars, where nuclear reactions jammed protons and neutrons together to make new atomic nuclei.

4.   On Sunday morning, Dr. Matalipova saw the new nuclei, from the fetal skin cells, in the host eggs.

5.   Time to build a new nucleus.