0
Add your answer:
Earn +20 pts
A lac repressor turns off the lac genes by binding to?
When the lac repressor binds to the O region, RNA polymerase is prevented from beginning the process of transcription. In effect, the binding of the repressor protein turns the operon "off" by preventing the transcription of its genes. (Prentice Hall Biology Book .....Chapter 12 page 310)
What prevents e coli from expressing the lac genes in its DNA all of the time?
The lac genes in E. coli are regulated by the lac operon, which is controlled by a repressor protein. The repressor binds to the operator region of the DNA, blocking the transcription of the lac genes. When lactose is present, it binds to the repressor, causing a conformational change that releases the repressor from the operator, allowing for the expression of the lac genes.
What is the function of the operator locus of a Lac operon a. Binding with RNA polymerase b. Identifying the substrate lactose c. Producing messenger RNA d. Coding for represser e. Binding wit?
The operator locus of a Lac operon functions as a binding site for the Lac repressor protein. This repressor protein binds to the operator in the absence of lactose, effectively blocking RNA polymerase from transcribing the genes responsible for lactose metabolism. When lactose is present, it binds to the Lac repressor, causing it to release from the operator, allowing RNA polymerase to transcribe the genes.
Describe the effect a repressor has on the lac operon when lactose is present?
When lactose is present, it binds to the repressor protein, causing a conformational change that prevents the repressor from binding to the operator region of the lac operon. As a result, RNA polymerase can transcribe the structural genes of the lac operon, leading to the production of enzymes involved in lactose metabolism.
What genes is not a part of the lac operon?
repressor gene
What causes the lac genes in E. coli to turn off?
A lac repressor turns off the lac genes by binding to the operator.
A lac repressor turns off the lac genes by binding to?
When the lac repressor binds to the O region, RNA polymerase is prevented from beginning the process of transcription. In effect, the binding of the repressor protein turns the operon "off" by preventing the transcription of its genes. (Prentice Hall Biology Book .....Chapter 12 page 310)
How does the presence of lactose enable RNA polymerase to transcribe the lac genes?
The presence of lactose enables RNA polymerase to transcribe the lac genes by inducing a conformational change in the lac repressor protein. This change prevents the lac repressor from binding to the lac operator, allowing RNA polymerase to access the promoter region and initiate transcription of the lac genes.
What prevents e coli from expressing the lac genes in its DNA all of the time?
The lac genes in E. coli are regulated by the lac operon, which is controlled by a repressor protein. The repressor binds to the operator region of the DNA, blocking the transcription of the lac genes. When lactose is present, it binds to the repressor, causing a conformational change that releases the repressor from the operator, allowing for the expression of the lac genes.
What is the function of the operator locus of a Lac operon a. Binding with RNA polymerase b. Identifying the substrate lactose c. Producing messenger RNA d. Coding for represser e. Binding wit?
The operator locus of a Lac operon functions as a binding site for the Lac repressor protein. This repressor protein binds to the operator in the absence of lactose, effectively blocking RNA polymerase from transcribing the genes responsible for lactose metabolism. When lactose is present, it binds to the Lac repressor, causing it to release from the operator, allowing RNA polymerase to transcribe the genes.
When lactose is present in bacterial does it prevent the blocking effect of the repressor protein and allow the transcription of lactose metabolizing genes?
Yes. A precursor to lactose binds to the repressor and prevents or relaxes its binding to the Lac operon.
Which aspect of lac operon regulation is an example of post-translational control?
The addition of a lactose molecule to the Lac repressor protein is an example of post-translational control in lac operon regulation. This modification prevents the Lac repressor from binding to the operator region, allowing for the transcription of the genes involved in lactose metabolism.
How does lactose cause the lac operon to turn on?
The lac repressor protein has a binding site for lactose itself.
Describe the effect a repressor has on the lac operon when lactose is present?
When lactose is present, it binds to the repressor protein, causing a conformational change that prevents the repressor from binding to the operator region of the lac operon. As a result, RNA polymerase can transcribe the structural genes of the lac operon, leading to the production of enzymes involved in lactose metabolism.
What genes is not a part of the lac operon?
repressor gene
Transcription of lactose-metabolizing genes is blocked when?
Transcription of lactose-metabolizing genes is blocked when the Lac repressor protein binds to the operator region of the lac operon. This typically occurs in the presence of glucose when lactose is absent or in low concentrations. The Lac repressor prevents RNA polymerase from transcribing the genes, leading to inhibition of lactose metabolism.
What does the lac operon lactose bind to?
The lac operon is a group of genes involved in metabolizing lactose. The protein Lac repressor binds to the operator site in the absence of lactose, blocking gene expression. When lactose is present, it binds to the Lac repressor, causing it to release from the operator and allowing transcription of the genes involved in lactose metabolism.
