Chapter 18 - Regulation of Gene Expression

Question 1

operator

Answer 1

In bacterial and phage DNA, a sequence of nucleotides near the start of an operon to which an active repressor can attach. The binding of the repressor prevents RNA polymerase from attaching to the promoter and transcribing the genes of the operon.

Question 2

operon

Answer 2

A unit of genetic function found in bacteria and phages, consisting of a promoter, and operator, and a coordinately regulated cluster of genes whose products function in a common pathway.

Question 3

repressor

Answer 3

A protein that inhibits gene transcription. In prokaryotes, repressors bind to the DNA in or near the promoter. In eukaryotes, repressors may bind to control elements within enhancers, to activators, or to other proteins in a way that blocks activators from binding to DNA.

Question 4

regulatory gene

Answer 4

A gene that codes for a protein, such as a repressor, that controls the transcription of another gene or group of genes.