Class 12th Biology 2018 Set1 Delhi Board Paper Solution
Question 17
Explain the roles of the following with the help of an example each in recombinant DNA technology:
(a) Restriction enzymes
(b) Plasmids
Answer
(a) Restriction enzymes: These are the molecular scissor that cut the DNA strand into fragment. The type of reotriction enzymes are: Endonuclease and Exonuclease.
Endonuclease cut the DNA sequence at the specific site where as exonuclease cut the DNA strands at the end.
(b) Plasmids: Plasmids are the double stranded circular DNA other than chromosomal DNA present in prokaryotes. Plasmids are used as vector in DNA technology because these are responsible to determine the phenotypic character.
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