1. DNA Structure

2. 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.

3. 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)

4. 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

5. 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.

6. Videos
(Basic DNA structure)
(Watson Crick discovery)
personal DNA testing
DNA testing for individuals with a history of family illness
Human Genome Project