Why during PCR that the RNA primer doesnt have to be removed

Why during PCR that the RNA primer doesnt have to be removed like during DNA replication

Solution

In DNA replication, three enzymes play crucial role those are named as DNA Pol I, II and III. Pol III is main replicating enzyme. All these three enzymes have two specific activities.

Those are 5\'-3\' polymerase activity and 3\'-5\' exonuclease activity (also called as Proof reading activity). Additionally Pol I have another activity which is 5\'-3\' exo nuclease activity. Using this activity this Pol I removes the RNA primer. In case of PCR, the DNA Pol what we are using, they doesn\'t have 5\'-3\'exonuclease activity. so, then can not remove RNA primer. To avoid this in PCR we are using a direct DNA primer.