Final answer:
Primers in PCR bind to repetitive sequences in the genome, marking the specific part of the PCR product that will be amplified.
Step-by-step explanation:
The primers in PCR bind to repetitive sequences in the genome, which mark the specific part of the PCR product that will be amplified. The primers are small DNA fragments that are complementary to the base sequence of the template DNA strands at the 3' ends. When the PCR reaction is initiated, the primers anneal to the template DNA strands and serve as starting points for DNA synthesis. As the DNA is amplified, the desired product is synthesized and can be visualized using techniques like gel electrophoresis.