Chapter 12, Problem 31A

Summary Introduction

To write:

Correct vocabulary that describes the given process

Introduction:

Gene regulation is the ability of an organism to control which genes are transcribed in response to the environment. Gene expression is regulated by the cell. There are different ways by which prokaryotes and eukaryotes control the expression of their genes.

Answer to Problem 31A

Operon

Explanation of Solution

In prokaryotes an operon controls the transcription of genes in response to changes in the environment. An operon is a section of DNA that contains the genes for the proteins needed for a specific metabolic pathway. An operon consists of an operator, promoter, regulatory gene and the genes coding for proteins.

The bacteria Escherichia coli (E. coli) respond to tryptophan through two operons; trp operon and lac operon.