Question: 92. Polymerase chain reaction (PCR) amplifies DNA following the equation.
(1) \mathrm{N}^{2}
(2) 2^{\mathrm{n}}
(3) 2 n+1
(4) 2 \mathrm{~N}^{2}
Answer: Option (2)
Explanation:
Polymerase chain reaction is a technique used to amplify a specific DNA segment in vitro.
In PCR, each cycle results in the doubling of the DNA molecules present.
After the first cycle, one DNA molecule becomes two molecules.
After the second cycle, the number of DNA molecules becomes four.
Thus, after n cycles,
the total number of DNA molecules is given by the equation 2^{n}.
This exponential amplification is the characteristic feature of PCR.
Hence, PCR amplifies DNA following the equation 2^{n}.