AP Bio Operons

Front

What are operons?

Back

Operons are clusters of genes under the control of a single promoter, allowing coordinated expression of related genes in prokaryotes.

Front

In which organisms are operons primarily found?

Back

Operons are primarily found in prokaryotes (bacteria).

Front

What is an inducible operon?

Back

An inducible operon is a type of operon that is usually off but can be turned on in the presence of a specific molecule (inducer).

Front

What is a repressible operon?

Back

A repressible operon is usually on but can be turned off when a specific molecule (corepressor) is present.

Front

What is the function of the promoter in an operon?

Back

The promoter is the binding site for RNA polymerase, initiating transcription of the operon.

Front

What role does the operator play in an operon?

Back

The operator is a segment of DNA that a repressor protein can bind to, blocking RNA polymerase and preventing transcription.

Front

What is a repressor protein?

Back

A repressor protein binds to the operator to inhibit transcription of the operon.

Front

What is an activator protein?

Back

An activator protein enhances the binding of RNA polymerase to the promoter, increasing transcription.

Front

What is the lac operon?

Back

The lac operon is a well-studied example of an inducible operon in E. coli that is involved in the metabolism of lactose.

Front

What happens to the lac operon when lactose is present?

Back

When lactose is present, it binds to the repressor, causing it to release from the operator, allowing transcription of the genes.