Bragg and his team were able to come up with a model of DNA that showed it with a double helix, two strands of biopolymers on the outside and pairs of nucleotides on the inside, and four nucleotides that form base pairs such that each step on the twisted ladder is made up of either adenine and thymine or guanine and cytosine. This model changed the paradigm of genetics and allowed a much deeper understanding of heredity.