Operon

Which of the following describes an operon that is active and becomes inactivated by a molecule binding to the repressor?

• inducible operon

• repressible operon

A protein that binds to the operator and blocks the RNA polymerase

• inducer protein

• repressor protein

• activator protein

• structural protein

The location of an operon that functions as an "on/off" switch and is where a repressor would bind

• promoter

• repressor

• operator

• structural gene

What is 4 in the diagram?

• RNA polymerase

• Inducer

• Repressor

• Operator

Tags

NGSS.HS-LS1-1

What is the role of operons in prokaryote gene expression?

• It makes the genes prokaryotes be turned on

• It accounts for the regulation of gene activity in response to the needs of the cells

• To make DNA for the gene

• To make the gene turn of and off

The lac operon is an example of an inducible operon. Which of the following describes the process that occurs when lactose is present?

• The lactose binds to the repressor which inactivates it and the repressor binds to the operator to turn translation on.

• The lactose binds to the repressor which activates it and the repressor releases from the operator to turn translation on.

• The lactose binds to the repressor which inactivates it and the repressor releases from the operator to turn translation on.

• The lactose binds to the repressor which activates it and the repressor binds to the operator to turn translation on.

In the lac operon the inducer is

• allolactose

• glucose

• galactose

• all of the above

What is 1 in the diagram?

• RNA polymerase

• Inducer

• Repressor

• Operator

Match the following genetic regions to their roles:

• Promotor

• Codes for the main protein / enzymes

• Regulatory gene

• Makes a repressor protein

• Genes of Operon

• Place where transcription begins

• Operator

• The on/off switch where the repressor protein binds

What term was coined by Jacob, Lwoff, and Monod in the 1960s to describe a unit of genetic function in bacteria?

• Gene

• Chromosome

• Operon

• DNA