In lac operon, both gene A and gene B undergo a transcription process. Gene B can only undergo transcription in the presence of lactose and in the absence of glucose. The product of gene A is often altered by an inducer. Which of the following is true about genes A and B? Select one: a. Gene A= structural gene; Gene B= regulatory gene b. Gene A= regulatory gene; Gene B= structural gene c. Gene A= promoter gene; Gene B= operator gene d. Gene A= lacZ gene; Gene B= promoter gene

In lac operon, both gene A and gene B undergo a transcription process. Gene B can only undergo transcription in the presence of lactose and in the absence of glucose. The product of gene A is often altered by an inducer. Which of the following is true about genes A and B? Select one: a. Gene A= structural gene; Gene B= regulatory gene b. Gene A= regulatory gene; Gene B= structural gene c. Gene A= promoter gene; Gene B= operator gene d. Gene A= lacZ gene; Gene B= promoter gene

Biology (MindTap Course List)

11th Edition

ISBN:9781337392938

Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. Berg

Publisher:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. Berg

Chapter14: Gene Regulation

Section: Chapter Questions

Problem 9TYU: A mutation that inactivates the repressor gene of the lac operon results in (a) the continuous...

See similar textbooks

Similar questions

A mutation that inactivates the repressor gene of the lac operon results in (a) the continuous transcription of the structural genes (b) no transcription of the structural genes (c) the binding of the repressor to the operator (d) no production of RNA polymerase (e) no difference in the rate of transcription
If the above gene is one of the three structural genes of the lac operon that codes for the protein/ enzyme responsible for breaking lactose into two molecules of simple sugars, what triggers the activation of this gene? a. Absence of Inhibitory protein b. Presence of lactose c. Absence of lactose d. Presence of Inhibitory protein e. Absence of Regulatory protein
If glucose levels in the cell are high and lactose is available from the environment, what is the status of transcription of the lac operon genes? Explain your answer from both an evolutionary perspective and in terms of negative and positive regulation of the operon?
In the lac operon, how would gene expression be affected if each one of the following segments was missing? A. lac operon promoter B. Operator site C. lacA gene
If glucose is not available, but lactose is available from the environment, what is the status of transcription of the lac operon genes? Explain your answer from both an evolutionary perspective and in terms of negative and positive regulation of the operon?
How will transcription of the E. coli trp (tryptophan) operon be affected by the following manipulations of the leader region of the trp mRNA?(a) Increasing the distance (number of bases) between the leader peptide gene and region 2(b) Increasing the distance between region 2 and region 3(c) Removing region 4(d) Changing several nucleotides in region 3 so that in can base pair with region 4 but not with region 2
If the two trp codons in the leader sequence were mutated to stop codons, what effect would it have on gene expression of that operon.
A strain of bacteria possesses a temperature-sensitive mutation in the gene that encodes the rho subunit. At high temperatures, rho is not functional. When these bacteria are raised at elevated temperatures, which of the following effects would you expect to see? Explain your reasoning for accepting or rejecting each of these five options. a. Transcription does not take place. b. All RNA molecules are shorter than normal. c. All RNA molecules are longer than normal. d. Some RNA molecules are longer than normal. e. RNA is copied from both DNA strands.
How will transcription of the E. coli trp operon be affected by the following manipulations of the leader region of the trp mRNA? - Changing several nucleotides in region 3 so that in can base pair with region 4 but not with region 2 - Removing region 4 - Increasing the distance between region 2 and region 3 - Increasing the distance (number of bases) between the leader peptide gene and region 2
A mutation occurs in the 5′ UTR of the trp operon that reduces the ability of region 2 to pair with region 3. What will the effect of this mutation be when the tryptophan level is high? When the tryptophan level is low?
A. A mutation is recovered in the gene that encodes the lactose operon repressor protein (LacI). Which of the following lac phenotypes would lead to the conclusion that the mutation causes an inability of the repressor to bind lactose? The lac structural genes would never be expressed. The lac structural genes would be expressed continuously. The lac structural genes would be expressed efficiently only in the absence of lactose. The lac structural genes would be expressed efficiently only in the presence of lactose. B. A mutation is recovered in the gene that encodes the lactose operon repressor protein (LacI). Which of the following lac phenotypes would lead to the conclusion that the mutation causes an inability of the repressor to bind Operator DNA? The lac genes would be expressed efficiently only in the presence of lactose. The lac genes would be expressed efficiently only in the absence of lactose. The lac genes would never be expressed. The lac genes would be…
A mutation in the operator region of the trp operon can prevent the trp repressor from binding to this operator. When these mutant cells are placed in a solution containing chicken broth, which of the following happens? a. Tryptophan would bind to the repressor. b. The Repressor would bind to the operator irrespective of the presence of amino acids in the environment. c. The transcription of the trip operon would be inhibited. d. The transcription of the repressor protein is inhibited