The importance of the egg's non-nuclear material - the cytoplasm - in early development is apparent in the consistent relation that is seen to exist between certain regions in the cytoplasm of a fertilized egg and certain kinds or directions of cell differentiation.

The aim of a nuclear-transplant experiment is to insert the nucleus of a specialized cell into an unfertilized egg whose nucleus has been removed.

Nuclear transplantation is a technique that has enormously facilitated the analysis of these interactions between nucleus and cytoplasm.

John Gurdon Quotes