Answer the following question given this paragraph: 

Prokaryotic cells are cells that lack a nucleus. The DNA in prokaryotic cells is in the cytoplasm, rather than enclosed within a nuclear membrane. All the organisms in the Bacteria and Archaea Domains have prokaryotic cells. No other organisms have this type of cell. Organisms with prokaryotic cells are called prokaryotes . They are all single-celled organisms. They were the first type of organisms to evolve. They are still the most numerous organisms today.


Q: What significant part of the cell do prokaryotic cells lack?


A:
a nucleus