Same chapter3 marksDifficulty: Medium
State Chargaff's rules and what they told Watson and Crick.
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3 marksDifficulty: Medium
Why is DNA replication described as semi-conservative, and whose experiment proved it?
Original Khojo Papers practice question — not from a past board paper.
Answer
Each new molecule of DNA has one strand from the parent molecule and one newly synthesised strand, so half the original is conserved in each daughter molecule. Meselson and Stahl proved it in 1958 using nitrogen isotope labelling and density gradient centrifugation of Escherichia coli DNA.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Their result ruled out both the conservative and the dispersive models.
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