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Nucleic Acid
Friedrich Miescher is a Swiss physician and biologist.
He could descovered nucleic acid.
What he did was isolate the genetic material from white the blood cell nuclei. He noted it had an acidic nature and called it nuclein. -
DNA Components
Phoebus Levene is a Lithuanian-American biochemist.
He was the one who discovered DNA complements.
The components are:
Adenine, guanine, cytosine, deoxyribose, phosphate. And defined phosphate-sugar-base units called nucleotides. -
Griffith Experiments
Griffith studied the epidemiology and pathology of 2 strains of Streptococcus pneumonia. Griffith's experiment, begun in 1928, was one of the first experiments to show that bacteria could transfer genetic information.
In 1928, Frederick Griffith, investigating various strains of pneumococcus, injected mice with the S strain and the R strain of the bacterium.
When the S strain was injected, there were no sequelae and the mouse lived. The R strain became the S strain. -
Pauling's Triple Helix
Linus Pauling and Robert Corey proposed DNA triple helix structure. With the same double helix distribution. But that turned out to be incorrect, because he was not very convinced of the model. -
Inside-Out double helix
Watson and Crick wrote an article describing DNA as a double helix with sugars and phosphates in the middle or inside and nucleobases outside. This model was shown to be incorrect and, in fact, to make no chemical sense. -
Rosalind Franklin photo 51
Rosalind Franklin took many pictures of the B form of DNA. She figured out how to see the wet shape and the shape that exists in cells. -
Chargaff's Rules and Hershey & Chase
The result could not be explained until 1944 when Avery, MacLeod, and McCarty cultivated the strain S After removing the lipids, proteins, and polysaccharides, the streptococcus still retained its ability to replicate its DNA and introduce it into pneumococcus R.
Griffith's heat inactivation would have left intact the DNA in the bacteria's chromosomes, which was responsible for the formation of the S gene. -
Watson and Crick Correct Double Helix
Maurice Wilkins obtained photo 51 from his desk. He passed it on to Crick and Waston. When they saw the image, they knew what it meant, and they knew their 1951 model was upside down. So they build the model based on Rosalind's photo 51.