Same chapter3 marksDifficulty: Medium
What is gel electrophoresis and what is it used for?
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3 marksDifficulty: Medium
Describe the three steps of one cycle of the polymerase chain reaction.
Original Khojo Papers practice question — not from a past board paper.
Answer
Denaturation at about 94 °C separates the two strands of the template DNA. Annealing at about 50 to 60 °C lets the primers bind to the complementary sequences flanking the region of interest. Extension at about 72 °C lets a thermostable Taq polymerase build the new strands from the primers. Repeating the cycle doubles the DNA each time.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Thirty cycles amplify the target sequence about a billion times.
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