Difference arises between well developed nucleus & less developed nucleus. The prokaryotes have well developed nucleus while the eukaryotes have advanced nucleus with nuclear membrane & nucleolus.
Eukaryotic cells differ from porkaryotic cells in that eukaryotes have a membrane bound nucleus which stores the genetic information in the cell in the form on DNA. In prokaryotic cells, the genetic information kind of just floats around the cytoplasm ...
The presence of a nucleus in an eukaryotic cell is what distinguishes it from a prokaryotic cell. The scientific name for eukaryote is eukaryota.
The nucleus and all membraned organelles.