Franklin and Wilkins analyzed DNA by bombarding DNA crystals with X-rays. Their analysis yielded two numbers that sparked interest, 3.4 nm and 0.34 nm. What is the significance of these numbers?
A) It turned out to be just a coincidence.
B) DNA molecules are 3.4 nm long and 0.34 nm wide.
C) The width of a DNA molecule is 3.4 nm, whereas the width of a nucleotide monomer is 0.34 m.
D) These numbers demonstrate there are 10 rungs, or steps, on the DNA "ladder" for every turn of the helix.
E) The 10 to 1 ratio signifies that DNA molecules are 10 times longer than they are wide.

Question

Quizplus · Accepted Answer

The 3.4 nm represents the length of one complete turn of the DNA helix, while 0.34 nm is the distance between adjacent base pairs. This means there are 10 base pairs (or "rungs") in each complete turn of the helix.

Franklin and Wilkins Analyzed DNA by Bombarding DNA Crystals with X-Rays