A. Formation of mRNA
B. Binding of lactose to repressor
C. RNA polymerase binds to promoter
D. Transcription of structural genes
E. Removal of repressor from operator
Choose the correct answer from the options given below :
Lac Operon Induction: Correct Sequence Explained
The lac operon in prokaryotes allows bacteria to regulate genes responsible for lactose metabolism. Its induction involves a specific sequence of events that enables the transcription of necessary genes when lactose is present.
Key Steps in Lac Operon Induction
Understanding the order of events is crucial for grasping how the lac operon functions:
- B: Binding of lactose (or its derivative, allolactose) to the repressor protein. This interaction is the initial trigger for induction.
- E: Removal of the repressor from the operator region. Lactose binding causes the repressor to detach, freeing the operator site.
- C: RNA polymerase binds to the promoter. With the operator clear, RNA polymerase can now attach to the DNA sequence upstream of the structural genes.
- D: Transcription of structural genes. Once RNA polymerase is bound, it begins synthesizing messenger RNA (mRNA) from the structural genes (lacZ, lacY, lacA).
- A: Formation of mRNA. The transcribed mRNA molecule carries the genetic code for the enzymes needed to metabolize lactose.
Therefore, the correct order of steps during lac operon induction is B, E, C, D, A.
This sequence ensures that the genes for lactose metabolism are only transcribed when lactose is available and the repressor is inactivated.
Similar Questions
- Arrange the following steps of crossing over in correct order :
A. Pachytene stage
B. Synapsis of homologous chromosomes
C. Separation of homologous chromosomes
D. Breakage and reunion of chromatids
E. Formation of chiasmata
Choose the correct answer from the options given below : - Arrange the steps in southern blotting in correct order :
A. Transfer of DNA to nitrocellulose membrane
B. Detection of hybridized probe
C. Restriction digestion of DNA
D. Hybridization with labelled probe
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Choose the correct answer from the options given below : - Arrange the steps of endospore formation in correct order :
A. Cortex and spore coat formation
B. Maturation and release of endospore
C. DNA replication and axial filament formation
D. Engulfment of forespore
E. Asymmetric septum formation
Choose the correct answer from the options given below : - Arrange the steps in antigen processing by endocytic pathway in correct order :
A. Recognition by CD4+ T cells
B. Antigen uptake by APC
C. Transport of MHC-peptide complex to cell surface
D. Peptide loading onto MHC class II molecule
E. Fusion of phagosome with lysosome
Choose the correct answer from the options given below : - Arrange the steps of agarose gel electrophoresis in correct order :
A. Preparation of agarose gel
B. Visualization under UV light
C. Loading of DNA samples
D. Migration of DNA fragments
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Choose the correct answer from the options given below : - Arrange the following steps of root nodule formation in correct order :
A. Formation of bacteroids and differentiation into nitrogen fixing symbiosomes
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Choose the correct answer from the options given below : - Arrange the steps of life cycle of phage T4 in correct sequence.
A. Lysis of the host cell
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C. Synthesis and assembly of phage components
D. Adsorption of the phage
E. Degradation of host DNA
Choose the correct answer from the options given below : - Arrange the following centrifugal speeds in an order to be used when a cell homogenate is to be separated into various fractions.
A. 1000 g
B. 80,000 g
C. 1,50,000 g
D. 20,000 g
E. 60,000 g
Choose the correct answer from the options given below : - Arrange the components of photosynthetic machinery of purple bacteria in a sequence followed for flow of electrons :
A. Quinone
B. P870
C. Cyt bC1 complex
D. Cyt C2
E. Pheophytin
Choose the correct answer from the options given below : - Arrange the steps in cloning and expressing a gene in correct order :
A. Introduction of recombinant molecule into new host that expresses the gene
B. Use of restriction enzymes or PCR to generate fragments of DNA
C. Protein purification
D. Isolation of DNA to be cloned
E. Generation of a recombinant molecule by inserting DNA fragments into vectors
Choose the correct answer from the options given below :
Important Questions from Mixed Topic (CUET PG)
- Who was the founder of Bolshevik Communist party?
- What is the key guide to statecraft in the realist tradition?
- Chronologically arrange the events in the Cold War period.
A. Berlin Wall is constructed
B. Communist China joins the UN
C. Soviet invasion of Czechoslovakia
D. Berlin Blockade
Choose the correct answer from the options given below: Morgenthau's principles of political realism are:
A. Politics is rooted in permanent and unchanging human nature which is basically self centred, self-regarding and self-interested
B. Politics is an autonomous sphere of action and cannot therefore be reduced to morals
C. International Politics is an arena of conflicting self-interests
D. The ethics of international relations is situational ethics which is very different from private morality
Choose the correct answer from the options given below:Who among the following political thinkers consider the anarchical self help system to be a compelling factor for States to maximise their relative power positions?
