Lac Operon

The lac Z gene codes for:

• permease

• beta-galactosidase

• repressor of lac operon

• transacetylase

In the bottom picture the operon is

• on

• off

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

• promoter

• repressor

• operator

• gene

Which of the following is not a structural gene?

• lac z

• lac y

• lac a

• lac I

The lac operon genes only become expressed if:

• lactose binds to repressor

• glucose binds to repressor

• repressor binds to operator

• lactose binds to operator

What does the lactose do to the Operon?

• Blocks transcription of the lactase gene by cutting up the DNA

• Binds to the repressor preventing it from attaching to the operator

• The lactose binds promoter to prevent transcription

• Allows for the transcription rate of lactase to slow down

In the top picture the operon is

• on

• off

What is an operon?

• a part of a ribsome

• a part of a RNA

• a unit made up of linked genes that code for proteins needed to do a specific task

• needed for dna replication

An operon consists of all the the following EXCEPT

• operator

• promoter

• regulatory gene

• genes of the operon

What does a promoter do?

• binds RNA polymerase for transcription

• binds DNA polymerase for replication

• binds the operator

• binds the repressor