Are red blood cells prokaryotic? After searching "do antibiotics impact the immune system" I found out that antibiotics target prokaryotic cells. It all made a lot of sense thinking about all those yogurt recommendations you get after taking antibiotics: the collateral damage is on the prokaryotic cells that live with us, but are not "us" as such. Except I remembered human red blood cells don't have nuclei, so where's my confusion? (I'm only a biology enthusiast.)

> Are red blood cells prokaryotic?

No!

1. There are many more differences between procaryotes and eukaryotes than just the presence of a nucleus. See DeNovo's answer for more information.

2. The terms procaryote vs eukaryote refer, not so much to the physiology of the cell but to a specific evolutionary lineage. Eukaryotes are individuals that belong to the monophyletic group of _Eukaryota_ aka. _Eukarya_ (see here for an intro to phylogeny). As such whether or not a eukaryotic loses its nucleus and start looking exactly like a E. coli won't change anything to the fact that this cell is still in the _Eukaryota_ lineage.