A scientist was observing an unknown slide under an electron microsocope; he found a cell without a well-defined nucleus but with a thick cell wall and ribosomes. What type of cell could it be?
Prokaryotic
Eukaryotic plant cell
Eukaryotic animal cell
Those cells are simpler and lack nuclei. Bacteria are such cells and archaea. The name implies that those are the cells that came into existence before the existence of karyon, which is actually the nucleus.