Question

Annealing process of PCR is performed at \(\_\_\_\) temperature.

• A. 90-98°C.
• B. 40-60°C.
• C. 70-75°C.
• D. 20-25°C.

Hint:

Annealing temperature in PCR depends on the melting temperature (\( T_m \)) of the primers and is typically 5°C lower than \( T_m \).

Answer 1

The Correct Option is B

The correct Option is : 2

Step 1: Understanding the PCR process.
Polymerase Chain Reaction (PCR) comprises three primary stages: 

Denaturation: DNA strands separate at elevated temperatures (90-98°C).

 Annealing: Primers attach to the template DNA at intermediate temperatures (40-60°C). 

Extension: DNA polymerase constructs the new strand at 70-75°C. 

Step 2: Annealing temperature. 
The annealing temperature is optimized (40-60°C) to facilitate primer hybridization with the template DNA while preventing non-specific binding. \[ \therefore \text{The annealing process of PCR is performed at 40-60°C.} \]