<prompt> Which of the following isare true about PCR except:Uses heat labile DNA polymeraseUses heat stable DNA polymeraseIs technique for DNA amplificationUsed to yield multiple copies of DNA  <response>: Ans: A Uses... Reverse transcriptase- PCR is used for qua notification ofRNA Harper 30th459, Lippincott 6th 483Polymerase Chain ReactionPCR provides a sensitive, selective extremely rapid means of amplifying a desired sequence of DNA. Twenty cycles provide an amplification of lOS 30 cycles of 109 -Harper 27th410-llSpecificity is based on the use of two oligonucleotide primers that hybridize to complementary sequence on opposite strands of DNA flank the target sequenceDouble stranded DNA can be disrupted by beat or high pH, giving rise to single stranded DNA. The single stranded DNAserves as a template for synthesis of a complementary strand by replicating enzymes, DNA polymeraseEarly PCR reaction used an PS coli DNA polymerase that was destroyed by each heat denaturation cycle. Substitution of a heat-stable DNA polymerase Taq polymerase 5 from Thermus aquaticus, obviates this problem has made possible automation of the reaction, since the polymerase reactions can be run at 70,CPCR is a cyclic process cycle contains three steps that involves Chatterjea ShindeDenaturation of DNA duplex 94-98degCAnnealing of primers 37-60oCExtension of the primers with a polymerase in the presence of dNTP about 72,:CUse of PCRIn detection of bacterial infections .retroviral infection latent virusApplication in forensic medicinerin prenatal diagnosis - in diagnosis of inherited diseaseIn cancer detectionQIn transplantationTo study evolutionIn sex determination ofembry-osTo determine viral loadIn DNA sequencingFig,; Steps in one cycle of the polymerase chain reaction. 