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Films · Biology · Molecular genetics

Explainer film · Molecular genetics

Three ideas, one tube

The end

Three ideas, one tube

Every new double strand is made of one old and one new strand: the tube of Meselson and Stahl showed it, and the replication fork builds it piece by piece.

Chapter 1 · Three suspects

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Three ideas, one tube

Biology · Molecular genetics

NewOct 18, 2026 · 4 chapters

An explainer film in four chapters: three ideas for how DNA copies itself, and one tube that decides between them. The Meselson–Stahl experiment, the machinery that builds new strands, and the problem at the end of every chromosome. Pause anywhere and ask.

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