Question

Is the cell in the diagram eukaryotic or prokaryotic?

Answer 1

the way I think of it is Eukaryotic has a true nucleus, and Prokaryotic doesn't.
a.k.a Eu, is true and Pro, is no

Answer 2

If you are unable to distinguish the nucleus clearly (like in microscope imagery), you can usually tell by looking at the flagellum. Prokaryotic cells have flagella, while true eukaryotic cells won't (exception of sperm cells)