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If lactose is present would the lac operon in a bacterial cell be on or off?
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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.
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.
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.
What must happen for transcription of the lac operon genes to take place?
Lac operon is a set of genes that regulates the digestion of lactose. In absence of lactose in the medium, the repressor protein binds to the operator that inhibit the transcription of structural genes such as beta galactosidase, lactose permease and transacetylase. This makes sure to avoid the enzyme synthesis when there is no need!Conversely, when the lactose present in the medium, an isomer of lactose called allolactose bind to the repressor protein, the conformational change in the repressor let it to detach from repressor hence the RNA polymerase can transcribe the structural gene. Although this may be enough for synthesis of structual gene the system is tightly regulated by a protein called CAP (catabolite activator protein) and glucose.Glucose is a preferred source of energy for cell when this desirable source is present, lactose need not be used as a energy resource. What happens is there will be low level of cAMP when there is high amount of glucose and this keeps CAP inactive.When there is low glucose levels, the cAMP would be higher, that binds to CAP to make it active, which in turn binds to the promoter that enhance the transcription of structural genes.Thus, for efficient transcription lac operon structural genes, lactose must be present where glucose must be absent.
How would you write a hypothesis about the relationship between bacterial reproduction and temperature?
the bacterial is doo doo
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.
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.
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.
What must happen for transcription of the lac operon genes to take place?
Lac operon is a set of genes that regulates the digestion of lactose. In absence of lactose in the medium, the repressor protein binds to the operator that inhibit the transcription of structural genes such as beta galactosidase, lactose permease and transacetylase. This makes sure to avoid the enzyme synthesis when there is no need!Conversely, when the lactose present in the medium, an isomer of lactose called allolactose bind to the repressor protein, the conformational change in the repressor let it to detach from repressor hence the RNA polymerase can transcribe the structural gene. Although this may be enough for synthesis of structual gene the system is tightly regulated by a protein called CAP (catabolite activator protein) and glucose.Glucose is a preferred source of energy for cell when this desirable source is present, lactose need not be used as a energy resource. What happens is there will be low level of cAMP when there is high amount of glucose and this keeps CAP inactive.When there is low glucose levels, the cAMP would be higher, that binds to CAP to make it active, which in turn binds to the promoter that enhance the transcription of structural genes.Thus, for efficient transcription lac operon structural genes, lactose must be present where glucose must be absent.
What would occur if the repressor of an inducible operon were mutated so it could not bind the operator?
It would result in the continuous transcription of the operon's genes.
What is an operon and in what type of cell would they be found?
prokaryotic cells
Glial cells present in large numbers in areas of bacterial infection in the brain would most likely be what?
Microglia.
What is the difference between prototrophs and auxotrophs?
Prototrophs are the wild type cells and would be the bacterial cells capable of utilizing certain nutrients or synthesizing certain compounds. Auxotrophs would be the mutant cells that are not capable of utilizing certain nutrients or synthesizing certain compounds. In the example of bacteria capable of utilizing Lactose as a nutrient source, the ability to lactose is denoted by lac+ and the inability to utilize lactose is denoted lac-.Prototrophs = lac+Auxotrophs = lac-
Why does eating cultured yogurt help some people with lactose intolerance?
Many people who cannot tolerate milk, either because of a protein allergy or lactose intolerance, can enjoy yogurt. The culturing process makes yogurtmore digestible than milk.and will not upset your stomach like other regular dairies would.
What exudate would be present in highest concentration at the site of persistent bacterial infection?
Pus. Green or yellow, depending on the bacteria responsible.
What would you assume if you found RNA transcripts of lactose-utilizing genes within E coli?
the presence of lactose
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?
a. Incorrect, the promoter binds RNAP b. Incorrect, the lac repressor identifies lactose c. Incorrect, the RNAP produces mRNA from the lacY, lacZ and lacA genes d. Incorrect, lacI codes for the repressor e. ?? By the process of elimination this would be the correct answer but the operator locus binds the *lac repressor* ("wit" is an unfamiliar designation).
