What does PCR stand for in molecular biology?

• A. Polymerase Chain Reaction
• B. Positive Control Reagent
• C. Polymerase Chain Reactionist
• D. Polymerase Chain Reagent

Answer: (A)

PCR stands for polymerase chain reaction. The name mirrors what the technique does: a DNA polymerase enzyme builds new DNA strands, the process proceeds through repeated cycles (a chain of steps) that exponentially amplify the target sequence, all inside a reaction mixture. In practice, this means heating to separate strands, cooling to let primers bind, and extending the new DNA with polymerase, then repeating these steps to produce many copies of the desired DNA fragment. It’s a standard term in molecular biology, not referring to a person or a specific reagent. The other options misidentify either the role of the components or the nature of the process itself.