Explain PCR and step by step process
Answers
Answered by
8
Answer:
The Polymerase chain reaction or PCR was originally invented by Kary Mullis in 1985 results in the selective amplification of the DNA (or RNA) present even as a single copy in initial preparation.
A single PCR amplification cycle involves three basic steps :-
- The target DNA is heated to a high temperature (usually 94° to 98° C ) resulting in the separation of the two strand . Each strand of the target DNA then act as template for DNA synthesis .
- The two oligonucleotide primers anneal (hybridize) to each of the single stranded DNA since sequence of the complementary to the 3' ends of the template DNA . This step is carried at a lower temperature (usually 40° to 60°) depending on the length and sequence of the primers .
- Taq Polymerase (from a thermophilic bacteria Thermus aquaticus ) synthesis the DNA region between the primers, using DNTPs (deoxynucleoside triphosphates) and Mg2+ . It means the primers are extended towards eachother so that the DNA segment lying between the two primers is copied. This Occurs at an optimum temperature of 72°C .
Hope this will help uh!!!
☺️❣️
Answered by
3
PCR Definition
Polymerase chain reaction (PCR) is a common laboratory technique used to make many copies (millions or billions!) of a particular region of DNA. This DNA region can be anything the experimenter is interested in. For example, it might be a gene whose function a researcher wants to understand, or a genetic marker used by forensic scientists to match crime scene DNA with suspects.
Steps involved
- PCR involves a process of heating and cooling called thermal cycling which is carried out by machine.
There are three main stages:
- Denaturing – when the double-stranded template DNA is heated to separate it into two single strands.
- Annealing – when the temperature is lowered to enable the DNA primers to attach to the template DNA.
- Extending – when the temperature is raised and the new strand of DNA is made by the Taq polymerase enzyme.
- These three stages are repeated 20-40 times, doubling the number of DNA copies each time.
- A complete PCR reaction can be performed in a few hours, or even less than an hour with certain high-speed machines.
- After PCR has been completed, a method called electrophoresis can be used to check the quantity and size of the DNA fragments produced.
♡♡H●P£.. ¡T.. H£LP$ ♡♡
Similar questions