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Why does copying chromosomes not double the number of sets?

A cell can copy its DNA while still retaining the same number of chromosome sets. Mitosis and meiosis organize those copies differently, with meiosis separating homologous chromosomes before separating sister chromatids. Tracking sets and copies as different quantities makes the two division processes easier to compare.

8–10 min

Questions you could explore

  • What changes at the first meiotic division that differs from mitosis?

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2–3 min

Why won’t an antibiotic treat a viral cold?

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