Gene Regulation and Operons

These flashcards cover key terms and concepts related to gene regulation and operons in prokaryotic and eukaryotic cells.

Prokaryotic Genome

Circular in shape, unlike the eukaryotic genome which is organized into chromosomes.

Housekeeping Genes

Genes that are needed all the time and are constantly being transcribed.

Gene Regulation

The process by which cells control the expression of specific genes.

Transcription Factors

Proteins that help turn genes on and off.

Operon

A cluster of genes under the control of a single promoter, commonly found in prokaryotic organisms.

Promoter Region

A sequence of DNA where RNA polymerase binds to initiate transcription.

Operator

Part of DNA where repressor proteins can bind to block transcription.

Lac Operon

A type of operon in bacteria that regulates the breakdown of lactose.

Repressor

A protein that binds to the operator to prevent transcription of certain genes.

Inducer

A substance that initiates transcription by preventing the repressor from binding to the operator.

Co-repressor

A molecule that binds to a repressor protein to enable it to bind to the operator, thus blocking transcription.

Tryptophan Operon (trp Operon)

An operon that regulates the production of tryptophan in bacteria based on its availability.

Post-transcriptional Control

Regulation that occurs after mRNA is formed and can prevent it from leaving the nucleus.

Translational Control

Regulation of the rate at which mRNA is translated into proteins.

Post-translational Control

Regulation of the activity of proteins after they have been translated.

RNA Polymerase

An enzyme that synthesizes RNA from a DNA template during transcription.

B-galactosidase

An enzyme responsible for the breakdown of lactose in E. coli.