Practice question

Hot Start PCR suppresses premature amplification by keeping Taq polymerase inactive at low temperatures during reaction setup. Inactivation is achieved via antibody-mediated inhibition, wax barriers, aptamers or chemical modification that block polymerase activity below activation temperature. At room temperature, primers can anneal nonspecifically and form primer-dimers that would otherwise be extended. By preventing extension until initial denaturation at 94-95°C restores active enzyme conformation, only specific primer-template duplexes formed at stringent annealing temperatures are amplified. SYBR Green is a detection dye, while modified dNTPs or pre-annealing blockers do not provide this temperature-dependent enzymatic control.