Same chapter3 marksDifficulty: Medium
Describe the three steps of one cycle of the polymerase chain reaction.
Biotechnology: Principles and Processes
3 marksDifficulty: Medium
What is gel electrophoresis and what is it used for?
Original Khojo Papers practice question — not from a past board paper.
Answer
Gel electrophoresis separates DNA fragments by size by driving them through an agarose gel with an electric field: because DNA is negatively charged it moves towards the anode, and smaller fragments move faster. The separated bands are stained with ethidium bromide and viewed under ultraviolet light. It is used to check a restriction digest and to isolate a fragment of a chosen size.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The process of cutting the band out of the gel and recovering the DNA is called elution.
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