Class 12th Biology 2017 Set1 Delhi Board Paper Solution
Question 19
Explain the role(s) of the following in biotechnology.
(b) Gel-electrophoresis
Answer
Gel-electrophoresis:
It is the technique which allows the visualisation of separated fragments of DNA on an agarose gel matrix. Since, the DNA fragments are negatively charged molecules, they separate and move towards the anode ( + ve) under the influence of an electric field. DNA fragments are separated on the basis of their size through the sieving effect provided by the gel.
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