The main difference between a eukaryotic cell and a prokaryotic cell is s presence of a nucleus. Namely, the prokaryotic cell has no nucleus. Its genetic material is free in the cytoplasm not coated by a membrane. Its DNA is short stranded. The prokaryotic cell also lacks in membrane-bound organelles. On the other hand, the eukaryotic cell has the nucleus. Its genetic material (long tangled strands of DNA) is not free in the cytoplasm, but it is packed in the nucleus. Presence of membrane-bound organelles is also a characteristic of the eukaryotic cell.