Final answer:
The steps of PCR are denaturation, annealing, and extension, which are used to amplify DNA. PCR's uses include genetic testing and forensics.
Step-by-step explanation:
The Polymerase Chain Reaction (PCR) technique is a powerful tool used in molecular biology to amplify DNA sequences. The three steps of PCR are:
- Denaturation: This step involves heating the DNA to break the hydrogen bonds between the two strands, resulting in single strands of DNA.
- Annealing: During this step, the temperature is lowered to allow primers to attach to the single-stranded DNA at complementary sites.
- Extension: Here, the enzyme Taq polymerase synthesizes a new strand of DNA, starting from the primers.
These steps are repeated in cycles to exponentially increase the amount of targeted DNA segment. There are numerous applications for PCR, including:
- Genetic testing, where it is used to identify genetic disorders or to check gene expression.
- Forensic science, where PCR can assist in criminal investigations by analyzing very small samples of DNA for identification purposes.