Which type of cells lack a nucleus?

Prokaryotic cells are characterized by their lack of a nucleus, which is a defining feature that distinguishes them from eukaryotic cells. In prokaryotes, such as bacteria and archaea, the genetic material is located in a region of the cell known as the nucleoid, rather than being enclosed within a membrane-bound nucleus as seen in eukaryotic cells. This absence of a nucleus contributes to several of the distinct functional and structural characteristics observed in prokaryotic cells, including their typically smaller size and simpler organization compared to eukaryotic cells.

Eukaryotic cells, on the other hand, are defined by the presence of a nucleus and other membrane-bound organelles. This structural complexity allows eukaryotic cells to perform more varied and specialized functions.

Animal and plant cells, which are both types of eukaryotic cells, also contain a nucleus. Therefore, they do not fit the criteria of cells lacking a nucleus.