In eukaryotes, chromatin ______ is a way to keep genes turned on and off.

• A. Decondensation
• B. Transcription
• C. Condensation
• D. Replication

Answer: (C)

Chromatin structure controls whether the cell’s transcription machinery can access DNA. When chromatin is compacted (condensed), promoter and enhancer regions are hidden, making it harder for RNA polymerase and transcription factors to bind and initiate transcription, which helps keep genes turned off. When chromatin loosens (decondenses), these regions become accessible, allowing genes to be transcribed. So chromatin condensation serves as a switch that helps regulate whether genes are active or silent. The other terms describe either the process of transcription itself or the opposite state or an unrelated process (decondensation is the less condensed state; replication is DNA copying).