No reason for doubt! SYBR green is used a lot as a cheaper alternative for Taqman probes. Here is how it works. SYBR green will bind to double stranded DNA, so it will bind to the original template DNA (present in low quantities) as well as to newly generated PCR products (increasing amounts during PCR). SYBR green will emit a strong fluorescent signal when it is bound to ds DNA but not when in solution. You are right, during PCR the SYBR green will fall off during the denaturation step, because DNA strands will denature. But it will bind again during the extension phase, when the amount of signal will be measured in the Real time PCR machine. Because SYBR green is not specific, it will bind to any ds DNA, including primer dimers. Therefore, at the end of the PCR, usually a “melting point” analysis (also called dissocation curve) will be done, in which the temperature is typically raised from 65 degrees C to 95 degrees C. At 65C, the PCR product will be double stranded, and it will bin