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Fredrich Miescher
Miescher is the beginning of the journey that is the discovery of DNA as he was first discovered it. Miescher discovered DNA in the nucleus of white blood cells by studying used bandages from a local clinic. This discovery added or our current understanding of DNA by discovering it in the first place -
Erwin Chargaff
By developing a paper chromatography method for separating and identifying small amounts of organic matter Chargaff found that between species, the nucleotide composition of DNA varies. Chargaff also found that the total amounts of purines and the total amount of pyrimidines are usually similar: "Chargaff's Rule".This discovery is important to our understanding of DNA because we understand that just because all DNA is made of A,C,T, and G, does not mean that the combinations are all the same. -
Hershey and Chase
Hershey and Chase found that only DNA is needed for viral replication by using radioactive isotopes to track proteins and DNA showing that most of the labeled protein does not enter the cell but remains attached to the bacterial cell membrane. This discovery contributed to our understanding of DNA by showing that viral cells do not need very much at all and can replicate only with DNA hence why illness spreads between organisms. -
Watson and Crick
Watson and Crick discovered the 3D double helix model of DNA. This discovery was made by creating models of the double helix out of cardboard and moving the cardboard structures around. Their argument added to our current understanding of DNA by representing how DNA appears in cells. -
Rosalind Franklin
Franklin discovered that phosphates were on the outside of a helical structure.Franklin concluded this by studying two pictures her student assistant got showing two sets of high-resolution photos of crystallized DNA fibers. This is a major contribution to our understanding of DNA by showing how nucleotides are bonded together in a strand of DNA. -
Meselson and Stahl
By growing bacteria cells and watching how they divide, Meselson and Stahl concluded that after DNA replication, DNA separates into two distinct strands when the cell divides and each daughter cell gets an identical strand. This discovery is important by alloeing us to understand where each cells gets its DNA from.
