Which of the following statements about PCR phases is accurate?

The accurate statement regarding PCR phases is that standard PCR measures during the exponential phase. In standard PCR, the goal is to amplify DNA to detectable levels, and this amplification occurs predominantly during the exponential phase of the PCR cycle. During this phase, the amount of PCR product doubles with each cycle, leading to a rapid increase in the DNA concentration.

In contrast, quantitative PCR (qPCR) is designed to measure the amount of DNA in real-time throughout the PCR process rather than only at the end. It provides quantitative data by analyzing the amplification during the exponential phase, allowing for accurate quantification of the target DNA.

Standard PCR does not typically measure after the run is complete, as it is primarily concerned with the amplification process itself rather than post-run analysis. The analysis of qPCR happens concurrently with the amplification process, providing data that reflects the state of the reaction during the exponential phase rather than waiting until the end of the run.