What are short sequences of single-stranded DNA used in PCR called?

In the context of PCR (Polymerase Chain Reaction), short sequences of single-stranded DNA are used to bind to the template DNA and initiate the amplification process. These sequences are known as DNA primers. Primers are designed to be complementary to the specific sequences at the start of the target DNA regions that need to be amplified. During PCR, the primers anneal to the single-stranded template DNA, providing a starting point for the DNA polymerase to extend and replicate the DNA. This is a crucial step in the PCR process, as it ensures that only the desired section of DNA is amplified.

The other options represent different components or functions in molecular biology but do not specifically refer to the sequences used to initiate DNA synthesis in PCR.