Molecular Biology Practice Test: Manipulation of Nucleic Acids & Polymerase Chain Reaction — Flashcards

Manipulation of Nucleic Acids & Polymerase Chain Reaction topics include: DNA manipulation, DNA and RNA hybridization, PCR fundamentals, inverse PCR, randomly amplified polymorphic DNA and reverse transcriptase PCR.

The polymerase chain reaction (PCR) is a technique that can amplify a specific DNA sample to allow for detailed study. It is a fundamental technique in genetic testing and research, and is used in many medical laboratory applications. 

PCR involves three main steps:
Denaturation of dsDNA template at 92–95°C
Annealing of primers at 50–70°C
Extension of dsDNA molecules 

PCR uses thermal cycling, which involves exposing reagents to repeated cycles of heating and cooling. This allows for different temperature-dependent reactions, such as DNA melting and enzyme-driven DNA replication. 
PCR can exponentially amplify a target sequence, which increases the likelihood of detecting target gene sequences in complex mixtures of DNA. The billions of copies of a specific DNA fragment or gene that PCR creates can be detected and identified using visual techniques based on size and charge. 
PCR can also amplify fragments of nucleic acids, which may represent dead microorganisms.