What were the scientific contributions that led to the discovery of DNA by these people. Frederick Griffith?
Frederick Griffith- discovered what he called the “transforming principle.” However, he was killed in a bombing raid during World War II while he was working, so his discovery wasn’t identified as DNA until after his death. Oswald Avery, Colin Macleod, and Maclyn McCarty- discovered that genes and chromosomes were formed from the biomolecule DNA. Alfred Hershey and Martha Chase- proved that DNA, not proteins, were what formed genetic material. James Watson and Francis Crick- discovered the structure of DNA molecules, known as the double helix. Rosalind Franklin- took the first X-ray diffraction images of the structure if DNA. Erwin Chargaff- discovered what are known as “Chargaff’s rules.” The first was that the number of guanine bases equals the number of cytosine bases, and that the number of adenine bases equals the number of thymine bases. The second rule was that the DNA varied from species to species.
