Name _________________________ DNA Timeline

1865 Gregor Mendel Publishes his findings about patterns of inheritance Charles Darwin published his findings about Natural Selection

1868 Friedrich Miescher Swiss biologist Studied nuclei of pus cells obtained from discarded surgical bandages Detected a phosphorus-containing substance that he named nuclein. Showed nuclein to consist of an acidic portion, known today as DNA, and a basic protein portion now recognized as histones

1902 Walter Sutton Using grasshopper chromosomes he showed that chromosomes occur in distinct pairs, which segregate at meiosis. Proposed that genes were located on chromosomes

Big Question… Since Chromosomes are made up of nucleic acids and protein …. Which molecule holds the genetic information – DNA or Proteins?

1928 Frederick Griffiths Proved that there was a transforming factor

1944 Avery, McCarty, & MacLeod Built on Griffith’s experiment to prove that DNA, not protein, was the transforming factor Looked at each of the organic compounds separately and only DNA passed on lethal traits

1951 Rosalind Franklin Used X-ray diffraction to show the shape of DNA to be a double-helix Famous photo 51 was taken by Wilkins without her knowledge Died in 1958 before Nobel prize was awarded in 1962

1951 Erwin Chargaff Showed that there were always equal amounts of Adenine (A) & Thymine (T) and equal amounts of Guanine (G) and Cytosine (C) in DNA Led to idea of Base pairing = Chargaff’s rule

1952 Alfred Hershey & Martha Chase Used bacteria and viruses to prove DNA held the genetic code

1953 James Watson & Francis Crick Master puzzle makers Used information from others and put it all together to realize the structure and function of DNA

Structure & Function – DNA vs. Protein Amino acids Acid backbone 20 different AA to code for millions of different proteins Order of Amino Acids determines specific protein DNA Nucleotides – 3 parts 5 C Sugar + phosphate (backbone) 4 different bases (rungs) Order of bases determine code for amino acids

Name _________________________ DNA  Amino Acid  protein

Ribosomes - site of Protein synthesis

1962 NOBEL PRIZE

DNA Timeline 1865 Mendel 1900’s Sutton Sex chromosomes 1905 1962 Nobel Prize Griffiths 1928 Ribosomes 1956 1953 Watson & Crick 1952 Hershey & Chase 1951 Franklin Chargaff 1944 Avery, McCarty & Macleod DNA first observed 1868 1984 DNA Fingerprinting 1997 Dolly cloned 2000-2003 Human Genome Project 1982 Genetically engineered insulin