Question

The total number of DNA molecules present after 5 cycles of polymerase chain reaction (PCR) starting with 3 molecules of template DNA is .................

Hint:

The total number of DNA molecules in PCR increases exponentially with the number of cycles. The formula is \( N = N_0 \times 2^n \), where \( N_0 \) is the initial number of molecules and \( n \) is the number of cycles.

Answer 1

Correct Answer: 96

Step 1: Understanding PCR amplification.
In PCR, the number of DNA molecules doubles with each cycle. If we start with 3 molecules, after \( n \) cycles, the total number of DNA molecules will be: \[ \text{Total number of molecules} = 3 \times 2^n \] where \( n \) is the number of cycles.
Step 2: Calculation.
After 5 cycles, the total number of DNA molecules is: \[ 3 \times 2^5 = 3 \times 32 = 96 \] Step 3: Conclusion.
The total number of DNA molecules present after 5 cycles of PCR is 96.