Here's why:

* Prokaryotic cells are simple cells that lack a nucleus and other membrane-bound organelles. They are found in bacteria and archaea.

* Plants and animals are made up of eukaryotic cells, which are much more complex. Eukaryotic cells have a nucleus, mitochondria, Golgi apparatus, and other organelles.

So, while both prokaryotes and eukaryotes are cells, they have distinct structures and functions.