PCR

• state the stages that happen in the PCR

  1. DNA needs amplification, primers, excess nucleotides , DNA polymerase the sample itself (DNA fragments) added to thermocycler
  2. 95 degree temp denatures the DNA strands and breaks the hydrogen bonds between bases so they separate
  3. Temp is decreased to 55-60 degrees. The primers (small nucleotides) anneal (join to complementary DNA bases), needed for the replication of the strands
  4. Temp increased to 72-75 degrees for one min, optimum temp for polymerase. Polymerase adds bases to primers, producing double stranded DNA identical to og sequence

  
• what are the advantages of PCR?

  • rapid
  • no living cells required- no complex culturing
  • can be done in vitro
  • Billions of copies can be produced
• what are the applications of PCR?

  • can monitor the spread of new infections/strains
  • classifying species
  • detect genetic diseases before conceiving and receive counselling
• why is PCR useful?

  allows scientists to produce a lot of DNA from the tiniest original sample