Question

Why prokaryotes don't have a nuclear membrane

Answer 1

Prokaryotes, by definition, are organisms in which the nucleus and other membrane-bound organelles are absent.Prokaryotes do have their genomic DNA concentrated and localized to a small area within the cell (nucleoid region). So it's not entirely accurate to say that prokaryotes don't have a nucleus. They do however lack a 'true' nucleus that is membrane bound. Having no true nucleus has its own advantages.