Gene Regulation and trp Operon Quiz

Genes that produce proteins which are part of the structure and function of a living organism.

Genes responsible for regulating the activity of other genes. They control if and at what rate other genes are expressed.

A regulatory gene whose product is a DNA binding protein that binds to DNA. Functioning in the regulation of gene expression.

A regulatory gene whose product is a signalling molecule. These molecules bind to their receptors on the cell surface and trigger a cascade of events, ultimately affecting gene expression.

Regulatory genes that control embryonic development.

Genes that control the expression of hundreds of other genes, playing a vital role in development.

A change in the DNA sequence of a homeotic gene leading to the appearance of body parts in unexpected locations.

A structure in flies that is analogous to the wings of some insects.

A cluster of genes that are transcribed together as a single unit, sharing a common promoter and operator.

The trp operon is a set of genes involved in the biosynthesis of tryptophan in bacteria like E. coli.

The trp operon is transcribed as a single mRNA molecule, leading to the production of all the enzymes needed for tryptophan synthesis at once.

A regulatory gene codes for a protein that controls the expression of other genes. These proteins can act as repressors, activators, or other regulatory factors.

Structural genes encode for RNA or protein products that are directly involved in cellular functions, such as enzymes or structural components.

Repression is a mechanism that restricts the transcription of genes by binding a repressor protein to the operator region.

The trp operon is repressed when tryptophan is present, preventing the synthesis of tryptophan-producing enzymes.

The repressor protein binds to the operator region in the presence of tryptophan, blocking RNA polymerase from transcribing the structural genes.

Attenuation is a form of gene regulation that stops transcription before completion, relying on the leader region of the operon.

The leader region contains a sequence that can sense tryptophan levels. When tryptophan is abundant, the leader region facilitates premature termination of transcription.

Attenuation provides an additional layer of regulation, ensuring that tryptophan synthesis is finely tuned to the cell's needs.

The lac operon regulates the expression of genes involved in lactose metabolism.

The lac operon is induced when lactose is present, allowing the production of enzymes needed to break down lactose.

The lac operon is repressed when glucose is present, as glucose is the preferred energy source.

The lac operon and the trp operon differ in their regulation mechanisms, with the lac operon being inducible and the trp operon being repressible.