There is no nuclear membrane. The cells having nuclear material without nuclear membrane are termed prokaryotic
cells. The organisms with these kinds of cells are called prokaryotes (pro : primitive; karyon : nucleus). Examples
are bacteria and blue green algae. The cells, like onion cells and cheek cells having well-organised nucleus with
a nuclear membrane are designated as eukaryotic cells. All organisms other than bacteria and blue green algae are called eukaryotes. (eu : true; karyon: nucleus).