Q54 / 180 · NEET 2026 (Re-NEET) · Botany
During PCR, primers bind to the DNA strands in the __________ step.
- Aligation
- Bdenaturation
- Cextension
- Correct answerDannealing
Solution
Polymerase Chain Reaction (PCR) involves three main steps:
1. Denaturation: The double-stranded DNA is heated to separate it into two single strands.
2. Annealing: The temperature is lowered to allow the oligonucleotide primers to bind (anneal) to their complementary sequences on the single-stranded DNA templates.
3. Extension: The temperature is raised, and Taq DNA polymerase synthesizes the new DNA strand by adding nucleotides to the primers.
Therefore, primers bind to the DNA strands during the annealing step.
Answer: annealing
1. Denaturation: The double-stranded DNA is heated to separate it into two single strands.
2. Annealing: The temperature is lowered to allow the oligonucleotide primers to bind (anneal) to their complementary sequences on the single-stranded DNA templates.
3. Extension: The temperature is raised, and Taq DNA polymerase synthesizes the new DNA strand by adding nucleotides to the primers.
Therefore, primers bind to the DNA strands during the annealing step.
Answer: annealing
Hence, the correct answer is option: 'D'.