What structure is present in eukaryotic cells but absent in prokaryotic cells?

• A. Cytoplasm
• B. Cell membrane
• C. Ribosomes
• D. Nucleus

Answer: (D)

Verified step by step guidance

1. Understand the basic differences between eukaryotic and prokaryotic cells. Eukaryotic cells have a defined nucleus, while prokaryotic cells do not.
2. Identify the structures listed in the problem: cytoplasm, cell membrane, ribosomes, and nucleus.
3. Recognize that cytoplasm, cell membrane, and ribosomes are present in both eukaryotic and prokaryotic cells.
4. Note that the nucleus is a membrane-bound structure that houses the cell's genetic material and is unique to eukaryotic cells.
5. Conclude that the nucleus is the structure present in eukaryotic cells but absent in prokaryotic cells.