Which cellular structure is found in eukaryotic cells but not in prokaryotic cells?

• A. Nucleus
• B. Cell wall
• C. Ribosome
• D. Plasma membrane

Answer: (A)

Verified step by step guidance

1. Understand the key difference between eukaryotic and prokaryotic cells: Eukaryotic cells have membrane-bound organelles, while prokaryotic cells do not.
2. Review the function of the nucleus: The nucleus is a membrane-bound organelle that houses the cell's genetic material (DNA) and is a defining feature of eukaryotic cells.
3. Analyze the other options: The cell wall, ribosome, and plasma membrane are found in both eukaryotic and prokaryotic cells, though their composition may differ.
4. Conclude that the nucleus is the correct answer because it is exclusive to eukaryotic cells and absent in prokaryotic cells.
5. Verify your understanding by recalling that prokaryotic cells have a nucleoid region instead of a nucleus, where their DNA is located but not enclosed by a membrane.