Question

6. Which of the following discoveries provided a critical clue to Watson and Crick in solving the structure of DNA? (1 point)

Answer 1

1. double helix model was proposed after getting the clue from chargaff rule purines = pyramidines 2. A = T ( this means A pairs with T) G = C (this means G pairs with C) A DNA strand with the sequence A-T-T-G-C-T is T-A-A-C-G-A 3. In all the species the nucleic acid is made of phosphate , sugar , nitrogenous base (A,T,C,G) only the number purines and pyrimidines vary.

Answer 2

6. C.) Chargaffs base ratios

7. B.) T-A-A-C-G-A

8. A.) Base ratios