DNA Structure

What is DNA?

In 1953 James Watson and Francis Crick developed a double helix model for DNA.

DNA consists of 2 strands that twist around each other.

DNA is made of nucleotides

DNA is made up of repeating building blocks called nucleotides

3 Parts of a Nucleotide A sugar A phosphate group One of 4 nitrogenous

bases (Adenine, Guanine, Cytosine or Thymine)

Complementary Pairing

The 2 strands are held together by hydrogen bonds between the nitrogen bases.

When the bases bond together they follow a specific pairing rule called complementary base pairing where A-T C-G

Rosalind Franklin

Watson and Crick built a DNA model that agreed with the X-ray images collected by Rosalind Franklin

James Watson, Francis Crick, and Maurice Wilkins received a Nobel Prize for the double-helix model of DNA in 1962, four years after Franklin's death at age 37 from ovarian cancer.

Videos

http://www.youtube.com/watch?v=qy8dk5iS1f0 (Basic DNA structure)

http://www.youtube.com/watch?v=sf0YXnAFBs8 (Watson Crick discovery)

http://www.pbs.org/wgbh/nova/teachers/body/personal-dna-testing.html- personal DNA testing

http://www.pbs.org/wgbh/nova/genome/media/2809_q056_14.html- DNA testing for individuals with a history of family illness

http://www.pbs.org/wgbh/nova/teachers/body/human-genome-project.html- Human Genome Project