What does primer do in dna replication

Let's imagine that you want to photocopy a volume of encyclopedias. This is similar to copying eukaryotic DNA. Loooooots of information to copy. If you have, say several friends who can help you photocopy, how will each friend know which pages to begin at and which pages to end at? How does it know where to begin and end copying a section of DNA? Let's say that you decide on using Post-It Notes to mark where one person begins and the other person will end.

This is similar to the function of the RNA primer. DNA polymerase can only "see" 3' ends. If there's no 3' end, it's basically blind! It has no idea where to begin! You actually figured it out yourself in your question : DNA polymerases can't add nucleotides directly to the split strand, that's why you need the primer. Having that primer site be RNA is important for avoiding errors and being able to recognize the spots to be filled in later. You can find some more discussion of this question here:.

A primer is a short nucleic acid sequence that provides a starting point for DNA synthesis. The area replicated between two primers is called an Okazaki fragment. What is the primer used for DNA replication? Jul 13, A primer is needed to start replication of the lagging strand. Explanation: In the diagram above, you can see that the leading strand is replicated by the DNA polymerase in a 3'-5' direction.

Hope this helped! Related questions Why does DNA polymerase proofread the new strand? Why are nucleotides added to 3' end? How does the base pairing rule affect DNA replication? How does dna replication relate to mitosis? How does DNA polymerase work? How does dna replication differ between prokaryotes and eukaryotes?

What are nucleotides?