Question

Describe the steps that constitute one cycle of reactions in PCR.

Answer 1

Answer:

Polymerase Chain reaction was first defined by Kary B. Mullis. In this reaction, a numbers of DNA or gene of interest is produced in vitro by using two sets of primers and the DNA polymerase enzyme. Each cycle of Polymerase chain reaction (PCR) has three steps named as following:

(i) Denaturation: It is the first step of polymerase chain reaction in which both the strands of double-stranded DNA are separated by the heat.

(ii) Primer annealing: It is the second step of polymerase chain reaction that allows the DNA primer to attach with the template.

(iii) Extension of primers: It is the last step of PCR in which enzyme Taq polymerase is used to synthesize new strands of DNA.

Answer 2

PCR also known as polymerase chain reaction.

It is use to amplify the number of copies of DNA upto one billion or more.

Each cycle of DNA had 3 steps -

Step 1 denaturing:- when the double-stranded template DNA is heated to separate it into two single strands.

Step 2 annealing:-when the temperature is lowered to enable the DNA primers to attach to the template DNA.

Step 3 extending:- when the temperature is raised and the new strand of DNA is made by the Taq polymerase enzyme.