The terms prokaryotic and eukaryotic refer primarily to the presence of a cellular nucleus.

Here's why:

* Prokaryotes are single-celled organisms that lack a membrane-bound nucleus. Their DNA is located in a region called the nucleoid, which is not enclosed by a membrane.

* Eukaryotes are organisms whose cells contain a nucleus. The nucleus is a membrane-bound organelle that houses the cell's DNA.

So, the key difference between prokaryotes and eukaryotes lies in the presence or absence of a true nucleus.