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Heavy nitrogen isotopes showed each new helix keeps one old strand. The figure is taken from Nobel Prize, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

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Yes. It sits on the Science shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

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The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

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Meselson and Stahl traced DNA copying

Heavy nitrogen isotopes showed each new helix keeps one old strand The 1958 experiment grew bacteria in a medium containing nitrogen-15 so their DNA became denser than usual. After switching to ordinary nitrogen, the DNA formed a single band at a middle density, then two bands. That pattern fits semiconservative replication, in which each daughter molecule keeps one original strand. It sits in Mondo's science collection, one of 200 facts that each trace back to the reference below.

Where this comes from

Nobel Prize

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More facts like this

DNA stores genetic instruction in a double helix structureFour nitrogenous base pairs form the chemical alphabet of living organisms Mutations supply new genetic variationCopying errors and damage create the alleles that selection can act on Mitochondrial DNA passes down the mother's lineEgg cells supply the mitochondria, so this DNA traces maternal ancestry Stretched DNA from a single cell measures about two metres longTightly packed chromosomes coil double-stranded DNA into tiny cell nuclei All human DNA combined would reach across the solar systemTrillions of cells containing two metres of DNA each span billions of kilometres Rutherford's gold foil found the nucleusA few alpha particles bounced back, revealing a tiny dense core

Tags: genetics, dna, experiment

Meselson and Stahl traced DNA copying: the short answers

Where does this come from, and can I check it?: Heavy nitrogen isotopes showed each new helix keeps one old strand. The figure is taken from Nobel Prize, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a science fact?: Yes. It sits on the Science shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.