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What would happen to the lac operon if a bacterium were growing in the presence of both glucose and lactose?
The regulatory portion of the operon is the only portion that would be transcribed.
Describe how E. coli uses the negative and positive control of the lac operon to economize on RNA and protein synthesis?
if a regulatory protein in its active state turns off the expression of the operon, the operon is said to be negatively regulated by the regulatory protein. if the regulatory protein in its active state truns on the operon, the operon is positively regulated by the regulatory protein. an operon regulated by a repressor is therefore negatively regulated, because the presence of the active repressor prevents transcription of that operon. in contrast, an operon regulated by an activator is positively regulated, because in its active state the activator protein turns on transcription of the operon under its control. the lac operon of E. coli repressor(lac repressor) is synthesized through the activity of the gene lac I, known as regulator gene. the active form of the lac repressor, is a tetramer that contains four copies of the gene I product. in the absence of the inducer, the repressor binds to the lac operator sequence, preventing RNA polymerase from binding to the promoter and transcribing the structural genes. thus the lac operon is negatively regulated associated with the lac operon, there is another site, 16 base pairs upstream of the promoter, which is used for a positive control of the gene expression. this site is called catabolic activator protein site or cyclic AMP(cAMP) protein site or catabolite gene activator(cga) site, because it is utilized for binding of CAP or cga to stimulate gene expression. CAP can bind to this site only when it is bound with cAMP. by binding to it, the CAP-cAMP complex exerts a positive control over the transcription process. it has an effect exactly opposite to that of repressor binding to an operator. yhe effector molecule cAMP determines the effect of CAP on lac operon transcription. presence of glucose inhibits the formation of cAMP and prevents it to bind to CAP
How many genes in the lac operon are found in e. coli?
My answer is 3, I am pretty sure I am right, but I would double check to make sure. I am in ninth grade taking biology at PineTree.
How does lactose cause the lac operon to turn on?
The lac repressor protein has a binding site for lactose itself.
The lac repressor releases the operator in the presence of glucose?
chickens and hens.
What would happen to the lac operon if a bacterium were growing in the presence of both glucose and lactose?
The regulatory portion of the operon is the only portion that would be transcribed.
Describe how E. coli uses the negative and positive control of the lac operon to economize on RNA and protein synthesis?
if a regulatory protein in its active state turns off the expression of the operon, the operon is said to be negatively regulated by the regulatory protein. if the regulatory protein in its active state truns on the operon, the operon is positively regulated by the regulatory protein. an operon regulated by a repressor is therefore negatively regulated, because the presence of the active repressor prevents transcription of that operon. in contrast, an operon regulated by an activator is positively regulated, because in its active state the activator protein turns on transcription of the operon under its control. the lac operon of E. coli repressor(lac repressor) is synthesized through the activity of the gene lac I, known as regulator gene. the active form of the lac repressor, is a tetramer that contains four copies of the gene I product. in the absence of the inducer, the repressor binds to the lac operator sequence, preventing RNA polymerase from binding to the promoter and transcribing the structural genes. thus the lac operon is negatively regulated associated with the lac operon, there is another site, 16 base pairs upstream of the promoter, which is used for a positive control of the gene expression. this site is called catabolic activator protein site or cyclic AMP(cAMP) protein site or catabolite gene activator(cga) site, because it is utilized for binding of CAP or cga to stimulate gene expression. CAP can bind to this site only when it is bound with cAMP. by binding to it, the CAP-cAMP complex exerts a positive control over the transcription process. it has an effect exactly opposite to that of repressor binding to an operator. yhe effector molecule cAMP determines the effect of CAP on lac operon transcription. presence of glucose inhibits the formation of cAMP and prevents it to bind to CAP
What is a clue that the lac operon is on?
The lac operon uses a two-part control mechanism to ensure that the cell expends energy producing the enzymes encoded by the lac operon only when necessary. In the presence of lactose, the lac repressor halts production of the enzymes encoded by the lac operon.
In Figure 84 which model of the lac operon correctly shows RNA polymerase lactose and repressor protein when the structural genes are being transcribed?
regulatory promoter oerator
Why is the lac regulatory system important to bacteria?
The lac regulatory system is a vital part of the bacteria. This is because, the most common source of food is sugar lactose and it is required by the enzymes all the time.
What environmental factor causes the lac operon to turn on?
In the lac operon model, lactose acts as in inducer molecule. In the presence of lactose, the molecule binds to the repressor protein. This repressor-lactose complex is unable to bind to the promoter. When the promoter is not occupied, RNA pol - II binds to it and begins transcribing the structural genes located downstream. Thus, the lac operon is turned on in the presence of lactose.
How many genes in the lac operon are found in e. coli?
My answer is 3, I am pretty sure I am right, but I would double check to make sure. I am in ninth grade taking biology at PineTree.
How does lactose cause the lac operon to turn on?
The lac repressor protein has a binding site for lactose itself.
What prevents e coli from expressing the lac genes in its DNA all of the time?
whenever the Lactose is present the lac genes in E.coli are turn on
The lac repressor releases the operator in the presence of glucose?
chickens and hens.
Use lac-rose in a sentence?
Lac Rose, also known as Lake Retba, is a salt water lake in Senegal that has pink waters due to the presence of an algae. An example of a sentence using "Lac Rose" is "We all visited Senegal and saw Lac Rose during the holidays. "
What region of the operon does the repressor bind to?
I assume you mean the lac operon. The repressor binds upstream of the gene(s) in the regulatory gene region.
