And these four individuals include Maurice Wilkins, rosalind Franklin, james Watson, and Francis Crick. Now what these four individuals essentially did is they were able to develop and study xray diffraction patterns of DNA five fibers. And from these x ray diffraction photographs they were able to deduce the following four points about DNA molecules. Point A if we examine any DNA molecule, the DNA molecule consists of two individual strands of nucleic acid. So we have two polynucleotide chains in a single DNA molecules and these two chains essentially run in an antiparallel fashion and they wind around a common access. And this can be described by the following diagram.