A. If the PCR shown in Figure 10–12 is carried through an additional two rounds of amplification, how many of the DNA fragments (gray, green, red, or outlined in yellow) will be produced? If many additional cycles are carried out, which fragments will predominate?

B. Assume you start with one double-stranded DNA molecule and amplify a 500-nucleotide-pair sequence contained within it. Approximately how many cycles of PCR amplification will you need to produce 100 ng of this DNA? 100 ng is an amount that can be easily detected after staining with a fluorescent dye.

Figure 10–12

Transcribed Image Text:

products of first cycle END OF FIRST CYCLE HEAT TO SEPARATE STRANDS AND COOL TO ANNEAL PRIMERS DNA SYNTHESIS SECOND CYCLE (produces four double-stranded DNA molecules) HEAT TO SEPARATE STRANDS AND COOL TO ANNEAL PRIMERS |QH| DNA SYNTHESIS THIRD CYCLE (produces eight double-stranded DNA molecules)