a.
Mutant 1 is inducible.
The presence of Z causes expression of the operon.
b.
Mutant 1 is constitutive.
The presence or absence of Z has no difference.
c.
Mutant 2 is uninducible.
As the promoter is inactive, it can not be induced.
d.
Mutant 3 is constitutive.
As the repressor binding site is mutated, repressor can not repress
the operon.
The presence of Z causes expression of the operon. So, it is an
inducer.
8. In afictitious bacteria, an operon induced by the presence of compound Z. A diagram of...
Briefly explain your answers to the following questions. A mutation (Mutation A) in the lac operon of E. coli leads to an inability to ferment lactose, and the expression of the operon is always off. Introduction into the mutant of an F' factor containing the wild type lac operon does NOT restore the ability to ferment lactose, i.e., there is no expression of the operon from the plasmid either. a. What is the probable nature of Mutation A? Is the...
please help me with the question 15 to 18. Basic structure of an operon Note that the diagram below is one section of DNA master strend with some areas of DNA labeled in blocks The bracketed area illustrates the basic parts of an operon repressor gene promoter operator structural genes DNA 3 mRNA 5 - 3 repressor protein shown attached to operator #2 Repressor preten "Use purple to color in the repressor gene. The repressor gene codes for a repressor...
1) The lac operon is… a) Positive repressible b) Both negative inducible and positive repressible c) Positive inducible d) Negative inducible 2) An activator regulatory protein… a) Is involved in negative regulatory control b) Is a cis acting regulatory element c) Recruits RNA polymerase to the promoter d) Prevents RNA polymerase from binding the promoter 3) For the lac operon, the presence of the substrate (lactose) activates the repressor. True or False? a) true b) false 4) cAMP… a) Activates...
Imagine you are carrying out research on the lac operon. You isolate six mutations in the lac operon by measuring the amount of beta-galactosidase made in mutant cell line under three different conditions: no lactose/no glucose; lactose only; and lactose/glucose. Your results are shown in the table. Strain No Lactose, No Glucose Lactose Lactose, Glucose Wild-type None High Low Mutant 1 None None None Mutant 2 None None None Mutant 3 None Low Low Mutant 4 None Low Low Mutant...
The lac operon consists of a promoter that initiates transcription of the gene i, which encodes a repressor protein. A seperate promoter, p, within the operon initiates transcription of z, which encodes B-galactosidase, and y, which encodes permease. The operator, o, where the repressor protein binds to inhibit transcription, is positioned between mutations, whereas superscript c denotes a constitutively active mutant. The table below sea fives the activity of B-galatosidase and permease for haploid and diploid mutant strains. Match the...
a regulated operon is turned on in the presence of a small molecule 'X'. A mutation that stops the synthesis of regulatory protein makes the operon permanently turned off. which type of regulator is the regulator protein, is it inducible or repressible? explain your answer using figures to show the operon expression in the presence and absence of regulator and also the presence and absence of the small molecule 'X'
In this problem you will explore how to solve problems involving partial diploid lac operon bacterial strains. Bacterial strains that are "partially diploid" have two copies of the lac operon because they aquired a plasmid carrying just the lac operon region. One copy of the lac operon region is on the recipient's bacterial chromosome, and the other copy is on the P plasmid that was introduced into the cell by conjugation. Partial diploid genotypes are written with the P segment...
In this problem you will explore how to solve problems involving partial diploid lac operon bacterial strains. Bacterial strains that are "partially diploid" have two copies of the lac operon because they aquired a plasmid carrying just the lac operon region. One copy of the lac operon region is on the recipient's bacterial chromosome, and the other copy is on the F' plasmid that was introduced into the cell by conjugation. Partial diploid genotypes are written with the F' segment...
QUESTION 8 The following situations (1-4) involve different types of gene regulation in prokaryotic cells as shown. OFF and ON reter to whether the gene is transcribed or not. Draw clearly-labelled regulatory proteins and effector molecules in each diagram to explain how the regulation works in each case. The first one has been done for you as an example a) (6 marks) Type of Regulation Regulatory protein effector molecule 1 DNA X negative inducible OFF ON 2 negative repressible DNA...
In the lac operon, 1 codes for the repressor protein, P is the promoter which is necessary for binding RNA polymerase, O is the operator, and Z codes for the B-galactosidase. Assuming (+) denotes the wild type for a particular locus, (-) denotes a lack of a particular gene product or function, O^c is a constitutive operator, and I^s is a super repressor. Use a "+++" sign to indicate that significant quantities of functional B-galactosidase are present, a '+' sign...