In eukaryotes, the DNA is held in the nucleus as which higher-order structures?

• A. Plasmids, organized into operons
• B. Polyribosomes, organized into polysomes
• C. Chromatin, organized into chromosomes
• D. Capsids, organized into virions

Answer: (C)

Verified step by step guidance

1. Understand that in eukaryotic cells, DNA is not free-floating but is packaged into complex structures to fit inside the nucleus and to regulate gene expression.
2. Recall that plasmids are small, circular DNA molecules typically found in prokaryotes, not eukaryotic nuclei, so they are not the correct structure here.
3. Recognize that polyribosomes (or polysomes) are clusters of ribosomes translating mRNA, not DNA structures, so this option is unrelated to DNA packaging.
4. Know that capsids and virions are related to viruses, where capsids are protein shells enclosing viral genetic material, so this is not relevant to eukaryotic nuclear DNA.
5. Conclude that in eukaryotes, DNA is wrapped around histone proteins forming nucleosomes, which further coil and fold to form chromatin, and chromatin is organized into chromosomes within the nucleus.