in vitro

• In vitro cloning of DNA / Polymerase Chain Reaction (PCR)

  1. Denaturing

  2. Primer annealing

  3. DNA synthesis
• In vitro


  Outside of a living organism, in the lab
• In vivo


  Inside of a living organism
• Equipment needed for PCR

  • Thermocycler
  • DNA fragment to be cloned
  • DNA polymerase (Taq polymerase)
  • Primers
  • DNA nucleotides
• Taq polymerase is obtained from bacteria that live in natural hot springs and has an optimum temperature much higher than regular DNA polymerase
• Primers are short sequences of single-stranded DNA that are complementary to the start and end of the DNA fragment being cloned
• PCR


  • Automated process
  • Rapidly produces billions of copies of a DNA fragment
  • Does not require living cells, just uses nucleotides and enzymes