Which scientist used X-ray diffraction to reveal the DNA double-helix structure?

Which scientist used X-ray diffraction to reveal the DNA double-helix structure?

• A. James Watson
• B. Rosalind Franklin
• C. Maurice Wilkins
• D. Erwin Chargaff

Answer: (B)

X-ray diffraction patterns reveal how atoms are arranged in a molecule by showing how X-rays scatter when they pass through a sample. For DNA, the distinctive pattern Franklin obtained indicated a regular, helical structure and provided crucial measurements that pointed to the DNA double helix. Rosalind Franklin used this technique to produce the famous diffraction images, which showed a cross pattern and helped establish the helical shape and dimensions of DNA. Watson and Crick later built the correct double-helix model, drawing on Franklin’s X-ray data along with Chargaff’s rules about base pairing. Chargaff studied the ratios of bases in DNA, which informed the pairing concept but did not come from X-ray diffraction. So, the scientist who used X-ray diffraction to reveal the DNA double-helix structure is Rosalind Franklin.

X-ray diffraction patterns reveal how atoms are arranged in a molecule by showing how X-rays scatter when they pass through a sample. For DNA, the distinctive pattern Franklin obtained indicated a regular, helical structure and provided crucial measurements that pointed to the DNA double helix. Rosalind Franklin used this technique to produce the famous diffraction images, which showed a cross pattern and helped establish the helical shape and dimensions of DNA. Watson and Crick later built the correct double-helix model, drawing on Franklin’s X-ray data along with Chargaff’s rules about base pairing. Chargaff studied the ratios of bases in DNA, which informed the pairing concept but did not come from X-ray diffraction. So, the scientist who used X-ray diffraction to reveal the DNA double-helix structure is Rosalind Franklin.