Review of the Lac Operon & Trp Operon exam Flashcards

An inducible operon that is typically off but can be activated by allolactose.

A repressible operon that is usually on but can be inhibited by tryptophan.

To metabolize lactose for energy.

To synthesize the amino acid tryptophan.

The repressor gene in the lac operon.

The repressor gene in the trp operon.

A lactose derivative that inactivates the lac I repressor.

The regulatory molecule that activates the trp R repressor.

Three genes: lacZ, lacY, and lacA.

Five genes: trpA, trpB, trpC, trpD, and trpE.

The lac I repressor is active, repressing transcription and turning the operon off.

The trp R repressor remains inactive, allowing transcription and turning the operon on.

An operon that is normally off but can be turned on by an inducer.

An operon that is normally on but can be turned off by a corepressor.

It inactivates the lac I repressor, allowing transcription to proceed.

It activates the trp R repressor, repressing transcription.

Lactose inactivates the repressor, turning the operon on.

Tryptophan activates the repressor, turning the operon off.

The three genes in the lac operon responsible for lactose metabolism.

The five genes in the trp operon responsible for tryptophan synthesis.

To repress transcription in the absence of lactose.

To repress transcription in the presence of tryptophan.

A molecule that activates a repressor protein to inhibit transcription.

A molecule that inactivates a repressor protein to initiate transcription.

The operon is turned on, allowing transcription.

The operon is turned off, repressing transcription.

The process of turning genes on and off to control gene expression.

Series of chemical reactions in a cell that build and breakdown molecules for cellular processes.

The lac operon is inducible (normally off), while the trp operon is repressible (normally on).