Ohio Assessment for Educators (OAE) Integrated Science (024) Practice Exam

What is the primary use of PCR (polymerase chain reaction)?

1. To edit DNA sequences

2. To copy and amplify DNA

3. To analyze RNA

4. For genetic sequencing

The correct answer is: To copy and amplify DNA

The primary use of PCR, or polymerase chain reaction, is to copy and amplify DNA. This technique allows scientists to make millions of copies of a specific DNA segment from a small initial sample. It involves a series of temperature changes that facilitate the denaturation of DNA, the annealing of primers to the target sequences, and the extension of these primers by a DNA polymerase enzyme. By amplifying DNA, PCR is an essential tool in various fields, such as medical diagnostics, forensic analysis, and genetic research. It enables researchers to analyze minute quantities of DNA, making it easier to study genetic information, detect pathogens, and conduct genetic testing. The ability to generate large amounts of DNA from a small sample is crucial for accurate analysis and experimentation in molecular biology. While DNA editing, RNA analysis, and genetic sequencing are important processes in genetics and molecular biology, they do not represent the primary purpose of PCR, which is centered specifically on the amplification of DNA.