HHMI Genetic Switches

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

• promoter
• repressor
• operator
• gene

what does a promoter do?

• it allows a gene to be transcribed
• it creates a DNA segment
• it is another word for ribosomes
• it is another word for RNA

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

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

• regulator
• repressor
• activator
• corepressor

A small molecule that binds to a repressor and makes it active

• repressor
• regulator
• activator
• corepressor

A small molecule that binds to the repressor and makes it inactive is

• corepressor
• inducer
• promoter
• operator

When a gene transcribes unless turned off by a repressor, it is considered _____ control

• negative
• positive

When a gene does not transcribe unless turned on by activator , it is considered _____ control

• positive
• negative

Two types of negative control are

• repressible & inducible
• repressible & active
• active & inactive
• repressible & corepressible