DNA DIGESTION AND ELECTROPHORESIS
In this experiment we will be doing a process called as DNA digestion or also known as restriction digest. A restriction digest is a procedure used in molecular biology to prepare DNA for analysis or other processing. It is sometimes termed DNA fragmentation, scientists Hartl and Jones describe it this way: This enzymatic technique can be used for cleaving DNA molecules at specific sites, ensuring that all DNA fragments that contain a particular sequence have the same size; furthermore, each fragment that contains the desired sequence has the sequence located at exactly the same position within the fragment. The cleavage method makes use of an important class of DNA-cleaving enzymes isolated primarily from bacteria. These enzymes are called restriction endonucleases or restriction enzymes, and they are able to cleave DNA molecules at the positions at which particular short sequences of bases are present. The resulting digested DNA is very often selectively amplified using PCR, making it more suitable for analytical techniques such as agarose gel electrophoresis, andchromatography. It is used in genetic fingerprinting, and RFLP analysis. 
Just as mentioned above, for this experiment we will be using restriction enzymes. Restriction enzymes or restriction endonuclease are enzymes isolated from bacteria that recognize specific sequences in DNA and then cut the DNA to produce fragments, called restriction fragments. They play a very important role in the construction of recombinant DNA molecules, as is done in gene cloning experiments.  Restriction endonucleases such as EcoRI recognize specific palindromic sequences and cleave a phosphodiester bond on each strand at that sequence. After digestion with a restriction endonuclease the resulting DNA fragments can be separated by agarose gel electrophoresis and their size can be estimated. A restriction map is generated by using the fragment size data to determine the location...
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