1. A(n) operon ______ is a stretch of DNA consisting of an operator, a promoter, and genes for a related set of proteins, usually making up an entire metabolic pathway.
An operon is often define as a functioning unit of DNA which contains cluster of genes that are together transcribed and controlled.
2. The genes of an operon ______ is/are arranged sequentially after the promoter.
These genes are transcribed together into an mRNA. After that they can be translated together or that mRNA can be spliced into monocistronic mRNAs that are translated separately.
3. A(n) promoter _______ is a specific nucleotide sequence in DNA that binds RNA polymerase, positioning it to start transcribing RNA at the appropriate place.
This sequence of DNA is necessary for gene expression since it initiates transcription.
4. A(n) regulatory gene ______ for a protein, such as a repressor, that controls the transcription of another gene or group of genes.
Regulatory gene is gene that encodes for the regulatory proteins such as repressors or activators.
5. Regulatory proteins bind to the operator ______ to control expression of the operon.
For example, operator is a segment of DNA to which a repressor binds and negatively controls gene expression.
6. A(n) repressor ______ is a protein that inhibits gene transcription. In prokaryotes, this protein binds to the DNA in or near the promoter.
Repressor is a DNA-binding molecule (protein) with regulatory role: it can inhibit the expression of one or more genes.
7. A(n) inducer ______ is a specific small molecule that binds to a bacterial regulatory protein and changes its shape so that it cannot bind to an operator, thus switching an operon on.
An inducer is a molecule that regulates gene expression by binding to repressors or activators: prevents the repressor from binding to the operator or helps activator binding to DNA.
