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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.
The presence of lactose in the environment causes the lac operon to turn on. When lactose is present, it binds to the repressor protein, causing it to release from the operator region of the lac operon, allowing RNA polymerase to transcribe the genes needed for lactose metabolism.
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Why is the tryptophan operon turned off in the presence of tryptophan?
The tryptophan operon is turned off in the presence of tryptophan because tryptophan acts as a corepressor. When tryptophan levels are high, it binds to the trp repressor protein. This trp-repressor complex then binds to the operator region of the operon, preventing RNA polymerase from transcribing the genes involved in tryptophan synthesis.
What is the role of lactose in regulating lac operon expression?
When the lac operon controls the expression of proteins in the E.coli cell that can break down lactose into two sugars, glucose and galactose. When lactose is present, it binds to the repressor that typically sits on the lac operon, changing the repressor's conformation such that it can no longer bind to the lac operon. Because of this, RNA polymerase can now transcribe the gene into mRNA, which in turn is translated into the proteins that can break down lactose.
Why do human bones turn green?
Human bones do not naturally turn green. If bones appear green, it may be due to factors such as algae growth due to environmental conditions or discoloration from chemicals or dyes. It is important to consult a medical professional if you notice any unusual changes in bone color.
What is the probably the most important factor affecting the distribution of biomes?
Climate is likely the most important factor affecting the distribution of biomes. Climate influences factors like temperature, precipitation, and sunlight, which in turn determine the types of plants and animals that can thrive in a particular area. This leads to the formation of different biomes such as forests, deserts, grasslands, and tundras.
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.
How does lactose cause the lac operon to turn on?
The lac repressor protein has a binding site for lactose itself.
What does the E coli the lac operon controls?
When the lac operon controls the expression of proteins in the E.coli cell that can break down lactose into two sugars, glucose and galactose. When lactose is present, it binds to the repressor that typically sits on the lac operon, changing the repressor's conformation such that it can no longer bind to the lac operon. Because of this, RNA polymerase can now transcribe the gene into mRNA, which in turn is translated into the proteins that can break down lactose.
What does the E coli the lac operon control?
When the lac operon controls the expression of proteins in the E.coli cell that can break down lactose into two sugars, glucose and galactose. When lactose is present, it binds to the repressor that typically sits on the lac operon, changing the repressor's conformation such that it can no longer bind to the lac operon. Because of this, RNA polymerase can now transcribe the gene into mRNA, which in turn is translated into the proteins that can break down lactose.
How do red factor canaries turn red?
The red canary was developed by a breeder named Dr. Hans Duncker. It can turn red because it was bred with a gene that causes this to happen.
Why is the tryptophan operon turned off in the presence of tryptophan?
The tryptophan operon is turned off in the presence of tryptophan because tryptophan acts as a corepressor. When tryptophan levels are high, it binds to the trp repressor protein. This trp-repressor complex then binds to the operator region of the operon, preventing RNA polymerase from transcribing the genes involved in tryptophan synthesis.
What is lac operon in E. coli?
The lac operon is a place on the DNA that binds to the DNA to stop the production of the RNA sequence to code for lactase (breaks down lactose) or binds to lactase to let the production of the RNA sequence to proceed.
What is the convention factor to turn liters into gallons?
The conversion factor is 0.26417
What causes causes the convection cell to turn up?
It is bumping into the lihosphere
How does foam turn sound into heat?
Sound is a vibration travelling through the air. When it hits foam, it causes the foam to vibrate, which in turn causes friction. The friction causes heat.
What causes a nose to turn blue?
alcohol
What causes fingernails to turn yellow?
dirt
Is burning diesel a chemical or a physical change?
It is a chemical process. The diesel gets compressed with air which in turn causes heat which in turn causes combustion.
