NEET BIOLOGY

Detailed explanation-1: -Chargaff’s realization that A = T and C = G, combined with some crucially important X-ray crystallography work by English researchers Rosalind Franklin and Maurice Wilkins, contributed to Watson and Crick’s derivation of the three-dimensional, double-helical model for the structure of DNA.

Detailed explanation-2: -Answer and Explanation: Watson and Crick are famous scientists who created a milestone by determining the structure of DNA. They used X-ray crystallography to identify that DNA is made up of two strands wrapped around each other to produce a double-helical structure.

Detailed explanation-3: -Which statement best describes how Watson and Crick’s model used other scientists’ work to create a model of DNA? They used Chargaff’s rule to determine that it contains ribose sugar.

Detailed explanation-4: -Watson and Crick took a crucial conceptual step, suggesting the molecule was made of two chains of nucleotides, each in a helix as Franklin had found, but one going up and the other going down. Crick had just learned of Chargaff’s findings about base pairs in the summer of 1952.

Detailed explanation-5: -It was only in 1953 that James Watson and Francis Crick, based on the X-ray diffraction data produced by Maurice Wilkins and Rosalind Franklin, proposed a very simple but famous Double Helix model for the structure of DNA.