Lac Operon

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

• regulator
• repressor
• activator
• corepressor

The "on/off" switch for an operon is called the

• promoter
• repressor
• operator
• gene

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

What is 2 in the diagram?

• RNA polymerase

• Inducer

• Repressor

• Operator

What is 4 in the diagram?

• RNA polymerase

• Inducer

• Repressor

• Operator

In the top picture the operon is

• on

• off

In the bottom picture the operon is

• on

• off

What is the name of the stretch of DNA where RNA polymerase binds?

• operator
• promoter
• enhancer
• origin

The lac operon genes only become expressed if:

• lactose binds to the repressor
• glucose binds to the repressor
• lactose binds to the operator
• the repressor binds to the operator