Question

Why do we need PCR primers?

Answer 1

PCR Primers:

1. Primers in PCR are short DNA strands that are usually 20 nucleotides long.
2. Two primer sequences are utilized for a PCR reaction and flank the ends of the target sequence.
3. They bind to the given template and the polymerase enzyme extends the strand based on this sequence.
4. Two types of primers are employed - forward primer and reverse primer.
5. The forward primer binds to the start codon while the reverse primer binds to the stop codon of the DNA template.
6. Primers are necessary for PCR sequence as polymerase enzymes are capable of adding nucleotides only to a pre-existing 3'-OH group and thus a primer sequence is a pre-requisite to add nucleotides.