FMS Science Complete Practice Test 2026

Prokaryotic cells are simple cells that lack a nucleus. Their genetic material sits in the cytoplasm in a region called the nucleoid, not enclosed by a membrane. They also do not have membrane-bound organelles like mitochondria or a nucleus, which are features of eukaryotic cells. Because of this, prokaryotes such as bacteria and archaea are typically unicellular and don’t form tissues in the way many organisms with nuclei do. So describing them as simple cells with no nucleus matches what they are, while stating they have a nucleus or membrane-bound organelles would be incorrect.