DNA: Deoxyribose Nucleic Acid

The Genetic Material

DNA • Deoxyribose nucleic acid type of nucleic acid

– What is the other type of nucleic acid?

• RNA• DNA function

– to hold genetic code – Genetic code = genetic

instructions to make proteins

• DNA is found in nucleus of eukaryotic cells

The Short History of DNA and Genetics (Part 1)

•From 1866-1953

Searching for Genetic Material• Gregor Mendel

(1866): – discovered that

inherited traits are determined by discrete units, or 'genes,’ - passed on from the parents.

• Freidrich Miescher(1868): – discovered DNA– Isolated something

new from the nuclei of eukaryotic cells

• Later called DNA!!!

Searching for Genetic Material• Thomas Hunt Morgan (1910):

– Worked with fruit flies• Specifically eye color of these flies!

– Discovered genes are located (linked) on chromosomes

Discovering the structure of DNA

Rosalind Franklin (1952)

•Obtained sharp X-ray diffraction photographs of DNA (Photo 51)•Watson and Crick used her data revealed its helical shape

•Watson and Crick went on to win Nobel Prize (1962) for their DNA model

Photo 51

How did PHOTO 51 reveal DNA’s helical shape?

•  X-rays passing through a helix diffract at angles perpendicular to helix making an "X" pattern, which favors an equal diameter "helix".

She finally gets credit Rosalind Franklin University of Medicine and

Science, located on Green Bay Road in North Chicago, Illinois

Discovering the structure of DNA James Watson & Francis Crick (1953)

•Discovered double helix structure•Solved the three-dimensional structure of the DNA molecule

Watson Constructing Bair Pairs movie

http://www.hhmi.org/biointeractive/dna/animations.html