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  • way explain how scientists figured out DNA's structure to unlock its mysteries.

  • Until the early 19 fifties, the structure of DNA remained a mystery.

  • At Cambridge University, Francis Crick and James Watson worked on making physical models of what DNA may look like.

  • Meanwhile, at King's College in London, Maurice Wilkins and Rosalind Franklin were also studying DNA by examining X rated fraction images of DNA.

  • In short, this means that when shining X rays through DNA molecules, the X rays made a shadow of the molecule structure.

  • Over time, different researchers made important but seemingly unconnected findings about the composition of DNA.

  • For example, Alexander Todd discovered that the backbone of the DNA molecule contained repeating phosphate and dioxide arrivals.

  • Sugar groups.

  • Linus Pauling discovered the single stranded Alfa helix, prompting biologists to think of helical forms.

  • He also pioneered the method of model building in chemistry.

  • Maurice Wilkins and Rosalind Franklin had obtained high resolution X ray images of DNA fibers.

  • It suggested a helical, corkscrew like shape.

  • Franklin suspected that all DNA was helical.

  • Phoebus, Levene and others discovered that DNA was composed of subunits called nucleotides.

  • A nucleotide is made up of a sugar ah phosphate group and one of four nitrogenous bases.

  • Thes are eight and nine Thing I mean guanine and cytosine.

  • Um Irwin charge off had found that 89 timing always appeared in ratios of 1 to 1, as did guanine and cytosine.

  • In the end, it was Watson and Crick who eventually unified all these findings to reveal DNA structure.

  • They used pollings method of model building in chemistry to uncover the structure of DNA, Franklin's double helix idea and char gaffes.

  • Findings about base pairs were incorporated into Watson and Crick's model.

  • This meant that matching base pairs interlocked in the middle of the double helix to keep the distance between the latter legs or backbones constant.

  • Finally, Watson and Crick realized that they always paired with tea and likewise see with G.

  • The base is connected to the two helical sugar phosphate backbones of DNA at right angles, so the legs retained their regular double helix shape.

  • Similarly, the complementary pairing of the base is meant that the backbones ran in opposite direction to each other, one up the other down.

  • And so Watson and Crick showed that each strand of the DNA molecule was a template for the other.

  • During cell division, the two strands separate and on each strand and new other half is built.

  • This'll DNA can reproduce itself without changing its structure.

  • This discovery opened many doors and biological research.

way explain how scientists figured out DNA's structure to unlock its mysteries.

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