What characterizes prokaryotic cells?

Prokaryotic cells are characterized by the absence of a membrane-enclosed nucleus. This foundational feature distinguishes them from eukaryotic cells, which do have a defined nucleus surrounded by a nuclear membrane. Instead, the genetic material in prokaryotic cells is located in a region called the nucleoid, which is not membrane-bound. This simplification of cellular structure allows prokaryotes, such as bacteria and archaea, to reproduce more rapidly compared to eukaryotic cells.

The other options present characteristics typical of eukaryotic cells or misunderstandings about cell structure. For example, eukaryotic cells have membrane-bound organelles, such as mitochondria and endoplasmic reticulum, which are absent in prokaryotic cells. In terms of size, prokaryotic cells are generally smaller than eukaryotic cells, not larger. Additionally, prokaryotic cells exist as single-celled organisms (like bacteria) and are not limited to multicellular organisms, which is a characteristic of many eukaryotes.