Sir/Mam, during DNA replication,what is tge role of a rna primer.Also why there is rna primer not dna primer?

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Solution

During DNA replication, RNA primer starts the new strand formation.Primer is a short RNA segment.
Primer is formed because the DNA polymerase can only extend an existing strand and cant start a new strand.
Because a new strand cant be formed by the DNA polymerase, a small RNA is formed which is extended by the DNA polymerase as DNA.
So RNA primer is starting the new DNA strand.That is the function of the RNA primer.
DNA primer is not there because DNA cant be formed from the beginning. DNA strand can only be extended from RNA primer.
After the replication , the primers are removed and new short DNA segment is formed in its place.

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Similar questions

Q. How many of the following statements are correct ?

A. DNA dependent DNA polymerase requires DNA primer for initiating replication but DNA dependent RNA polymerase does not require any primer for transcription.

B. DNA dependent DNA polymerase requires RNA primer for initiating replication but DNA dependent RNA polymerase does not require any primer for transcription.

C. During replication, unwinding of DNA double helix forms a fork-like structure called replication fork.

D. During transcription, unwinding of the DNA double helix by DNA dependent RNA polymerase forms a transcription bubble.

E. During transcription, unwinding of DNA double helix by DNA dependent RNA polymerase forms a transcription fork.

Which of the following properites of DNA polymerise necessitates the requirement of RNA primer in DNA replication?

Match the following enzymes of DNA replication with their respective functions:

p. DNA polymerase i. Helps unzip the DNA double helix

q. DNA ligase ii. Seals nicks between Okazaki fragments

r. DNA helicase iii. Lays RNA primers to which polymerase can add nucleotides

s. Primase iv. Adds nucleotides to the free 3’ end of RNA primers

Q. In DNA replication, the primer is

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$\begin{matrix} p . D N A p o l y m e r a s e & i . H e l p s u n z i p t h e D N A d o u b l e h e l i x q . D N A l i g a s e & i i . S e a l s n i c k s b e t w e e n O k a z a k i f r a g m e n t s r . D N A h e l i c a s e & i i i . L a y s R N A p r i m e r s t o w h i c h p o l y m e r a s e c a n a d d n u c l e o t i d e s s . P r i m a s e & i v . A d d s n u c l e o t i d e s t o t h e f r e e 3^{'} e n d o f R N A p r i m e r s \end{matrix}$

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