Question

You run a PCR reaction for five cycles starting with a single DNA duplex. Theoretically, how many copies of your sequence would you now have?

8
24
12
16
32

Answer 1

32

Step-by-step explanation:

PCR is a technique that amplifies a small DNA sample. When a single molecule of a double-stranded DNA enters the first round of PCR, each of the two strands of the DNA serves as a template and results in the formation of two new DNA molecules. If the second round of PCR is performed and both molecules of DNA enter it, each of them would be amplified into two DNA molecules. So, there are 4 DNA molecules by the end of the second round of PCR. If five rounds of PCR are carried out starting with a single DNA molecule, a total of 2^5= 32 DNA molecules will be obtained at the end.