-
Fredrick Griffith
He was studying R-strain ans S-strain. He then injected these into mice. His results of the mice dying from s-strain showed that a substance could be transferred to harmless bacteria and make it deadly. -
Period: to
DNA
-
Oswald Avery
He tried to answer the question that was raised by Griffith with a team. His team inactivated substances in S-strain bacteria. They then killed S-strain bacteria and mmixed it with live R-strain.The R-strain was deadly to injected mice when they inactivated proteins. This showed that the proteins weren't the genetic material because the R-strain was deadly without the S-strain. -
Alfred Hershey and Martha Chase
They did experiments with viruses and bacteria."viruses are not cells' to reproduce a virus its oen gentic material or bacterium must be inserted. His research confirmed that DNA is genteic material. -
Rosalind Franklin
She did X-ray diffraction. Using it she found basic structure of the DNA. She also found the helic structure. -
Watson and Crick
They discovered that Dna has a double heliix shape -
Erwin Chargaff
He was interested in the 4 nitrogen base of DNA. He found that they differed from spcies to species. He found that the Adenine always has the same concentration as Thymine and guanine always has the same concentration as cytosine.
