molecular configuration

Imagine DNA as a twisted ladder or spiral staircase - that's what we call a "helix." Before this research, scientists knew DNA was important for heredity but didn't know what it looked like. Franklin and Gosling used a technique called X-ray crystallography, which is like taking a shadow picture of molecules using X-rays instead of regular light. When they aimed X-rays at DNA crystals, the shadows they captured showed a distinctive pattern that revealed DNA's twisted shape. They also discovered that DNA can change its form depending on how much moisture is around it, and that the "backbone" of the DNA molecule (the phosphate groups) sits on the outside of the structure. This was like finally seeing the blueprint of life itself.