Question

Which of the following is the correct order of events in the polymerase chain reaction (PCR)? See Section 20.2 (Page 468)

cooling to allow primers to attach; heating to separate double-stranded DNA; elongation of DNA strand as nucleotides are added

elongation of the DNA strand as nucleotides are added; cooling to allow primers to attach; heating to separate double-stranded DNA

heating to separate double-stranded DNA; cooling to allow primers to attach; elongation of DNA strand as nucleotides are added

heating to allow primers to attach, elongation of DNA strand as nucleotides are added, cooling to separate double-stranded DNA In the process of producing recombinant DNA using human DNA, __________ is used to connect human and plasmid DNA together. See Section 20.2 (Page 468) a restriction enzyme DNA polymerase DNA ligase RNA polymerase The beginning point for synthesis of a new strand from a complementary single stranded piece of DNA is marked by __________. See Section 20.1 (Page 467) DNA polymerase gel electrophoresis primers nucleotides After introducing recombinant plasmids into bacteria, the next step toward producing clones of a desired human gene would be which of the following? See Section 20.2 (Page 468) cutting the plasmid DNA with restriction enzymes mixing human DNA fragments with cut plasmids isolating DNA plasmids and the human DNA of interest selecting the bacteria containing the human gene of interest and allowing it to reproduce adding DNA ligase to join plasmid and human DNA strands

Answer 1

heating to separate double-stranded DNA; cooling to allow primers to attach; elongation of DNA strand as nucleotides are added is the correct order of events in the polymerase chain reaction (PCR).

In the process of producing recombinant DNA using human DNA, DNA ligase is used to connect human and plasmid DNA together.( restriction enzyme used to cut DNA , polymerase used for synthesis of DNA, RNA polymerase used for synthesis of RNA from DNA)

The beginning point for synthesis of a new strand from a complementary single stranded piece of DNA is marked by primers

( primers are synthetic, known sequence segment of DNA which are complementary to target DNA sequence and provide free OH site for polymerase to start synthesis. )

After introducing recombinant plasmids into bacteria, the next step toward producing clones of a desired human gene would be selecting the bacteria containing the human gene of interest and allowing it to reproduce (selection of transformed bacteria is necessary to avoid false positive results.