What is the difference between replication of DNA and amplifcation of DNA in PCR?

Answer 1

DNA cloning is where you take a piece of DNA and put it in a host cell so that every time the host cell replicates, its daughter cells will have that exact copy of DNA.

DNA amplification is just taking a piece of DNA and making copies of it, like in the process of PCR. it is not inside a host cell.

another way to think of it: you can amplify a gene--make a bunch of copies of it, and then clone it (by putting it in a cell and once that cell replicates each daughter cell has a copy of that DNA). you don't need to amplify anymore in cloning, you already did that before.

Answer 2

Replication of DNA is a naturally occurring process but the PCR amplification is the induced amplification of DNA.

When we talk about DNA replication, it is a highly coordinated set of reactions that occur in the cell in the guidance of specialised replication machinery consisting of many enzymes. The DNA replication involves

1. The unwinding of DNA strands (Denaturation): This is done by a helicase enzyme.

2. DNA Priming: This is done by a primase enzymes that synthesises a short RNA fragment that initiates the DNA synthesis.

3. DNA synthesis: In which the DNA is synthesised using the parent DNA strand at template.

In PCR amplification:

The denaturation takes place by an elevated temperature ( nearly 92o - 96oC).

There is no primase enzyme. Synthesised primers are added. That anneal to the DNA strand at the lower temperature (nearly 54oC)

And then a thermostable Polymerase elongates the DNA.

Thus in replication there is no variation of Temperature but in PCR amplification there is a temperature variation.

In one round of DNA replication almost whole of the DNA is replicated but the PCR has an amplification limit, there is a length of nucleotides that could be amplified.

Finally, the most striking difference is that in replication on one of the strands (Lagging strand) the replication is discontinuous, while on other (Leading Strand) it is continuous. But in PCR amplification synthesis on both the strands is continuous.

Answer 3

in cloning gene of interest along with molecular carrier is introduced into an expression system while PCR is a process in which DNA polymerase is used that carries out DNA replication over and over again untill millions of copies of single gene or specifif sequence of DNA is formed.