Which of the following is a key difference between prokaryotic and eukaryotic cells?

• A. Prokaryotic cells have membrane-bound organelles, eukaryotic cells do not
• B. Eukaryotic cells lack a nucleus, while prokaryotic cells contain one
• C. Prokaryotic cells lack a nucleus and membrane-bound organelles, whereas eukaryotic cells possess both
• D. Eukaryotic cells are always unicellular, while prokaryotic cells are multicellular

Answer: (C)

Prokaryotic cells are characterized by their simpler structure and lack of compartmentalization. A key difference is that prokaryotic cells do not have a nucleus; instead, their genetic material is located in a region called the nucleoid. They also lack membrane-bound organelles, meaning that structures like mitochondria, endoplasmic reticulum, and Golgi apparatus, which are present in eukaryotic cells, are absent in prokaryotes.

In contrast, eukaryotic cells have a defined nucleus that contains their DNA, allowing for more complex regulation of gene expression and cell function. Additionally, the presence of membrane-bound organelles allows eukaryotic cells to compartmentalize various biochemical processes, increasing efficiency and providing more specialized functions.

Understanding these structural differences is fundamental to distinguishing the two cell types, as it underpins many aspects of their biology, including metabolism, growth, reproduction, and interaction with their environment.