Question

__________________ conducted X-ray diffraction studies on DNA and concluded what about the size and shape of DNA molecules? _______________ suggested the bases were stacked like pennies, _________________ indicated a helical structure.

Answer 1

Rosalind Franklin's X-ray diffraction studies were pivotal in elucidating the double-helix structure of DNA, with William Astbury suggesting the stacking of bases, and Watson and Crick piecing together the double helical model, which led to their Nobel Prize win.

Step-by-step explanation:

Rosalind Franklin conducted X-ray diffraction studies on DNA, which were critical in determining the size and shape of DNA molecules. Her well-defined X-ray diffraction images of DNA fibers revealed the overall double-helix structure of DNA. William Astbury suggested that the bases of DNA were stacked like pennies, while James Watson and Francis Crick used Chargaff's rules alongside Franklin and Wilkins' X-ray diffraction images to piece together the purine-pyrimidine pairing of the double helical DNA molecule. Their work culminated in the publication of the model of the DNA double helix in Nature. In 1962, Watson, Crick, and Wilkins were awarded the Nobel Prize in Physiology or Medicine for this discovery, though Rosalind Franklin's crucial contributions are often noted as she did not share in the Nobel Prize, having died before the prize was awarded.