Chapter 14, Problem 1STP

Summary Introduction

Introduction :

Prokaryotes are single-celled organisms that do not contain any nucleus and their DNA is found inside the cytoplasm. In prokaryotes, the process of transcription and translation occurs simultaneously to synthesize protein.

Answer to Problem 1STP

Correct answer :

The correct answer is option (D) transcription factor.

Explanation of Solution

Explanation/justification for the correct answer :

Option (D) is transcription factor. In prokaryotes the gene expression is regulated by regulating the transcription process. The transcription factors are used for this purpose. These proteins activate or inhibit the process of transcription. Hence, this option is correct.

Explanation for incorrect answer :

Option (A) is DNA pairing. DNA pairing is the pairing of nucleotide bases in the double-stranded strand by hydrogen bonding. In DNA, guanine pairs with cytosine and adenine pairs with thymine. It has no role in regulating gene expression. Hence, this option is incorrect.

Option (B) is repressor proteins. Repressor protein inhibits the process of transcription by blocking RNA pol attachment to the promoter. Hence, this option is incorrect.

Option (C) is RNA interference. RNA interference is a process in which gene expression is inhibited by neutralizing mRNA molecules. Hence, this option is incorrect.