A. Formation of Okazaki fragments which are of 1000 to 2000 nucleotides
B. Helicase unwind the helix with the help of topoisomerase like DNA Gyrase
C. DNA polymerase I or RNase H removes the RNA primer and polymerase I synthesizes complementary DNA to fill the gap
D. A special RNA polymerase 'primase' synthesizes a short RNA primer complementary to DNA
E. Fragments are joined by the enzyme DNA ligase
Choose the correct answer from the options given below :
DNA Replication Sequence in E. coli
DNA replication involves several critical steps orchestrated by specific enzymes. Understanding the correct order is essential for comprehending the process in organisms like E. coli.
Correct Sequence of DNA Replication Steps
The ordered sequence of events in DNA replication in E. coli is as follows:
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Helicase Unwinds DNA Helix
Step B: The replication process initiates with the unwinding of the DNA double helix. Enzymes like Helicase break the hydrogen bonds between base pairs. Topoisomerase (e.g., DNA Gyrase) manages the resulting supercoiling.
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RNA Primer Synthesis
Step D: DNA polymerases require a starting point (a 3'-OH group) to synthesize new DNA. The enzyme Primase, a type of RNA polymerase, synthesizes a short RNA primer complementary to the template DNA strand.
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Okazaki Fragment Formation
Step A: DNA synthesis proceeds using DNA polymerase. On the lagging strand, replication is discontinuous due to the 5' to 3' directionality of DNA polymerase. This results in the formation of short DNA segments called Okazaki fragments, typically 1000-2000 nucleotides long in prokaryotes.
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Primer Removal and DNA Gap Filling
Step C: After the Okazaki fragments are synthesized, the RNA primers must be replaced with DNA. Enzymes such as RNase H or the 5' to 3' exonuclease activity of DNA Polymerase I remove the RNA primers. DNA Polymerase I then fills the gaps with DNA nucleotides.
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Fragment Joining by DNA Ligase
Step E: The final step involves sealing the nicks between the newly synthesized DNA fragments. The enzyme DNA Ligase catalyzes the formation of phosphodiester bonds, joining the fragments into a continuous DNA strand.
Therefore, the correct sequence is B, D, A, C, E.
Similar Questions
- Consider the Earth to be a blackbody with an average temperature of $15^\circ\text{C}$. Find out the wavelength ($\lambda_{max}$) at which maximum power is radiated :
- Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : Under adiabatic conditions, a moist air parcel cools slowly and rises to greater height in atmosphere compared to a dry air parcel.
Reason (R) : Compared to dry air parcel, latent heat of condensation released within the moist air parcel reduces rate of cooling of the moist air parcel moving up under adiabatic conditions.
In the light of the above statements, choose the most appropriate answer from the options given below : - Arrange the following elements on increasing order of their mass (weight) percentage in the Bulk earth :
A. Iron
B. Silicon
C. Oxygen
D. Magnesium
E. Nickel
Choose the correct answer from the options given below : - Arrange the following Epochs of Cenozoic era starting from recent one to older one :
A. Paleocene
B. Pliocene
C. Oligocene
D. Holocene
E. Eocene
Choose the correct answer from the options given below : - Arrange following rock types from high grade to low grade metamorphism :
A. Slate
B. Gneiss
C. Schist
D. Shale
E. Phyllite
Choose the correct answer from the options given below : - Arrange the following Seismic discontinuities based on their depth of occurrence from shallow to deeper :
A. Conrad discontinuity
B. Repetti discontinuity
C. Gutenberg discontinuity
D. Lehman discontinuity
E. Mohorovicic discontinuity
Choose the correct answer from the options given below : - Match List - I with List - II.
List - I (Decomposition Processes) List - II (Function) A. Leaching I. Degradation of humus by microbes to release inorganic nutrients B. Catabolism II. Accumulation of a colloidal dark coloured amorphous substance, which is a reservoir of nutrients C. Humification III. Bacterial and Fungal enzymes degrade detritus into simpler inorganic substances D. Mineralization IV. Water soluble inorganic nutrients go down into the soil and get precipitated
Choose the correct answer from the options given below : - Choose the correct statements :
A. Both hardness and Alkalinity are measured in units of mg/L as $\text{CaCO}_3$
B. Enrichment of C and S are responsible for eutrophication of lakes
C. Alkalinity is a base neutralizing capacity
D. Dissolved ions increases salinity of water
E. Turbidity is a measure of transparency of water
Choose the most appropriate answer from the options given below : - Arrange the following materials in decreasing order of their porosity (percentage of total volume of material that consists of pore spaces) :
A. Sand
B. Clay
C. Gravel
D. Sandstone (Semi consolidated)
Choose the correct answer from the options given below : - Which of the following are examples of Igneous rocks ?
A. Batholiths
B. Stock
C. Argillacous
D. Gneiss
E. Zeolite
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?
