(i) Mention the number of primers required in each cycle of polymerase chain reaction (PCR). Write the role of primers and DNA polymerase in PCR.
(ii) Give the characteristic feature and source organism of the DNA polymeras, in PCR.

Explanation

Each cycle of PCR requires two sets of primers.
Role of primers : Primers are complementary to the regions of DNA. They anneal to botJ the strands of DNA which are then extended using nucleotides.
Role of DNA Polymerase :
(a) The enzyme extends the primers using the nucleotides provided in the reaction and th, genomic DNA as template.
(b) DNA polymerase used in PCR is thermostable and is called Taq polymerase. It is obtained form the bacterium Thermus aquaticus.