Which type of cell lacks a nucleus and membrane-bound organelles?

Prokaryotic cells are characterized by their lack of a nucleus and membrane-bound organelles. In these cells, the genetic material is not enclosed within a membrane but instead is found in a region called the nucleoid. This structural simplicity allows prokaryotic cells, such as bacteria and archaea, to reproduce quickly and adapt to various environments. The absence of organelles like mitochondria or chloroplasts also means that prokaryotic cells have emerged as one of the earliest forms of life on Earth, demonstrating that complexity is not always a requirement for survival and function.

In contrast, eukaryotic cells, which include plant and animal cells, possess a defined nucleus enclosed by a membrane and contain various organelles that perform specific functions, contributing to the overall complexity and specialization of these cells.