Which statement describes eukaryotic cells?

• A. They have no nucleus
• B. They have no organelles
• C. They have a nucleus
• D. They lack a cytoskeleton

Answer: (C)

Having a nucleus defines eukaryotic cells. In these cells, the genetic material is stored inside a membrane-bound nucleus, which keeps DNA segregated and organized and allows more complex regulation of gene expression. This distinguishing feature sets them apart from prokaryotic cells, which lack a true nucleus and hold their DNA in a diffuse, non-membrane-bound region. Eukaryotic cells also contain various membrane-bound organelles and a well-developed cytoskeleton that supports cell shape and movement. So, describing eukaryotic cells as having a nucleus captures their defining characteristic. The other statements don’t fit because lacking a nucleus would describe prokaryotes, lacking organelles ignores the many internal compartments present in eukaryotes, and lacking a cytoskeleton contradicts the internal framework that helps organize and transport materials inside these cells.