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

• A. Ribosomes
• B. Cytoplasm
• C. Cell membrane
• 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: ribosomes, cytoplasm, cell membrane, and nucleus.
3. Recognize that ribosomes, cytoplasm, and cell membranes are present in both eukaryotic and prokaryotic cells.
4. Recall that the nucleus is a membrane-bound organelle that houses the cell's genetic material and is a defining feature of eukaryotic cells.
5. Conclude that the nucleus is the structure present in eukaryotic cells but absent in prokaryotic cells.