The figure below illustrates two levels of DNA packing in a eukaryotic cell. Conformation B is an enlargement of the area in Conformation A, indicated by the start of the arrow. In which conformation is transcription most likely to occur?

Question

Quizplus · Accepted Answer

In Conformation B, the DNA is less condensed and more accessible to RNA polymerase, which can bind to regulatory DNA sequences and initiate transcription. In Conformation A, the tight coiling of chromatin may prevent access to regulatory DNA sequences and hinder transcription. Tight coiling only occurs during mitosis and has no direct relation to transcription. Histones are positively charged proteins that do bind to negatively charged DNA, but they play a role in gene regulation by exposing or concealing regulatory DNA sequences, not by physically preventing transcription.

The Figure Below Illustrates Two Levels of DNA Packing in a Eukaryotic