Question

What conditions does the DNA undergo during PCR?

1) Denaturation, Annealing, Extension
2) Denaturation, Elongation, Amplification
3) Denaturation, Replication, Amplification
4) Denaturation, Transcription, Translation

Answer 1

During PCR, DNA undergoes denaturation, annealing, and extension to make many copies of a target DNA sequence. These steps occur in multiple cycles with specific temperature changes to allow DNA strand separation, primer binding, and new strand synthesis.

Step-by-step explanation:

The DNA undergoes three specific conditions during Polymerase Chain Reaction (PCR): denaturation, annealing, and extension. During PCR, multiple cycles of these three steps are carried out to make many copies of a target DNA sequence. The process begins with denaturation, where the double-stranded DNA is heated to around 95°C, which separates it into two single strands. Next, during annealing, the temperature is lowered to approximately 50°C to allow primers to bind to their complementary sequences on the single-stranded DNA. Finally, in the extension step, the temperature is raised to around 72°C to enable the heat-stable DNA polymerase to add nucleotides to the primer, extending the DNA strand and replicating the target sequence.