Question

Where do the two primers of primer pair A anneal?

A) To any STR marker with the same repeat sequence
B) To the polymerase
C) To the tandem repeat sequence of STR marker A
D) To unique sequences on each side of STR marker A

Answer 1

The two primers of primer pair A specifically anneal to unique sequences on each side of STR marker A, enabling the amplification of that specific DNA segment during PCR.

Step-by-step explanation:

The two primers of primer pair A anneal to unique sequences on each side of STR marker A. During the polymerase chain reaction (PCR), these primers are synthesized to be complementary to specific target sequences on opposite strands of the DNA. This allows for the amplification of the DNA segment between the primers. The primer must match the sequence precisely to bind, or 'anneal,' thus ensuring specificity in the PCR process. Owing to the specificity of the primers, they do not anneal to any STR marker or the polymerase itself, but specifically to the sequences flanking the STR marker of interest.