Animal cloning process. Illustration of the stages in cloning an animal. In the laboratory, a cell is cultured (petri dish at top left) to produce a cell nucleus (orange) with source DNA (deoxyribonucleic acid). An egg cell has its nucleus removed by a micropipette (top right). The source DNA nucleus is placed in the egg cell (upper centre). An electric shock fuses the cells, opens the nuclear membrane (centre) and triggers cell division (lower centre). After a few cycles of division, an embryo (ball of cells, bottom centre) has formed. Implanted in a surrogate mother, it will develop into a clone of the original. For this artwork with labels, see C023/8902.