Chapter 12, Problem 35A

Summary Introduction

Introduction:

It is very important that cells control the expression of genes so that different genes are expressed at different times in an organism’s life. Gene regulation is the ability of an organism to control which genes are transcribed in response to the environment. In eukaryotes, gene regulation is a very complex process. One way of eukaryotic gene regulation is through proteins called transcription factors.

Answer to Problem 35A

Correct answer :

The correct answer is option C. Activator proteins fold DNA to enhancer sites that increase the rate of gene transmission.

Explanation of Solution

Explanation/justification for the correct answer:

Option C. Activator proteins fold DNA to enhancer sites that increase the rate of gene transmission− It is gene regulating mechanism in eukaryotic cells that controls transcription. Regulatory proteins called activators fold DNA so that enhancer sites are close to the complex and increase the rate of gene transcription. Hence this is the correct option.

Explanation for incorrect answer:

Option A. Eukaryotic gene regulation is exactly like prokaryotic gene regulation- In eukaryotes, gene regulation is a very complex process. The organization and structure of eukaryotic cells is more complex than prokaryotic cells, increasing the complexity of control system.

Hence this is not the correct option.

Option B. Replication factors guide the binding of eukaryotic RNA polymerase to the promoter- Transcription factors and not replication factors guide and stabilize the binding of eukaryotic RNA polymerase to the promoter. Hence this is not the correct option.

Option D. Repressor proteins bind to activators, preventing them from binding to the DNA- Repressor proteins bind to specific sites on the DNA and prevent binding of activators.

Hence this is not the correct option.