Describe the process of PCR, including what is needed.

Chemical components needed: a DNA template, DNA polymerase enzyme, primers, nucleotides and reaction buffer.

Steps in PCR:

  1. Denaturation 96 degrees, to seperate DNA strands

  2. Annealing 55-65 degrees, cool so that primers can bind to their complementary sequences

  3. Extension 72 degrees, raise temperature so that polymerase can work to extend primers making new DNA

KS

Related Biology A Level answers

All answers ▸

Describe three differences between a motor neurone and a sensory neurone.


DNA mismatch repair enzymes repair mainly bases on the newly synthesised DNA strand, using the old DNA strand as a template. If the mismatches were simply repaired without regard for which strand served as template, would this reduce replication errors ?


Explain how a plant is able to make glucose from carbon dioxide.


The genetic code is described as degenerate, universal and overlapping. Explain these terms.