Question

________ attract proteins which direct formation of heterochromatin preventing further transcription initiation.

A) Enhancers
B) Silencers
C) Promoters
D) Insulators

Answer 1

Enhancers bind transcription factors to silence gene expression, while promoters activate transcription. Silencers prevent further transcription initiation by directing the formation of heterochromatin.

Step-by-step explanation:

Enhancers bind transcription factors to silence gene expression, while promoters activate transcription. Enhancer regions are binding sequences for transcription factors that, when bound, change the shape of the DNA and allow activators bound to enhancers to interact with transcription factors bound to the promoter region and the RNA polymerase. Silencers, on the other hand, prevent further transcription initiation by attracting proteins that direct the formation of heterochromatin, which is a tightly packed form of DNA that prevents transcription.