Operon Review

Front

What is an operon?

Back

A group of genes that are regulated together and transcribed as a single mRNA molecule.

Front

What is the function of the operator in an operon?

Back

It is the site where a repressor protein can bind to block transcription.

Front

What is the role of the promoter in an operon?

Back

It is the region where RNA polymerase binds to initiate transcription.

Front

What is a repressor protein?

Back

A protein that binds to the operator to prevent transcription of the operon.

Front

What is an inducer in the context of operons?

Back

A molecule that binds to a repressor, causing it to release from the operator and allowing transcription.

Front

What is the difference between inducible and repressible operons?

Back

Inducible operons are usually off and can be turned on by an inducer; repressible operons are usually on and can be turned off by a repressor.

Front

What is the trp operon?

Back

A repressible operon that is involved in the biosynthesis of the amino acid tryptophan.

Front

What is the lac operon?

Back

An inducible operon that is involved in the metabolism of lactose.

Front

What is negative control in gene regulation?

Back

A mechanism where a repressor protein inhibits gene expression.

Front

What is positive control in gene regulation?

Back

A mechanism where an activator protein enhances gene expression.