Here's why:

* Eukaryotic cells have a true nucleus that contains their DNA, as well as other membrane-bound organelles.

* Prokaryotic cells lack a nucleus and other membrane-bound organelles. They have their DNA in a region called the nucleoid, which is not enclosed by a membrane.

Plant cells have a nucleus, mitochondria, chloroplasts, endoplasmic reticulum, Golgi apparatus, and other organelles, all of which are characteristic of eukaryotic cells.