operons

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

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

You want your bacterial culture to grow well so you made an enriched media with all forms of carbohydrates. Which of this carbohydrate should you restore first if you want the culture to keep growing at the same rate?

• Glucose

• Lactose

• Galactose

• Fructose

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

• operator
• promoter
• enhancer
• origin

Inducible negative control is when when the gene is transcribed by the ____ of a specific molecule

• presence
• absence

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

• inducible operon

• repressible operon

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.

The trp operon is an example of an repressible operon. Which of the following describes the process that occurs when tryptophan is present?

• The tryptophan binds to the repressor which inactivates it and the repressor binds to the operator to turn translation off.

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

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

• The tryptophan binds to the repressor which activates it and the repressor binds to the operator to turn translation off.

In the trp operon, the tryptophan binds to the repressor. Which of the following is the term used to describe this molecule?

• inducer

• corepressor

• enhancer

• CAP