Learn about the experiments by Frederick Griffith, Oswald Avery, Alfred Hershey, and Martha Chase that led to the discovery of DNA as the genetic material.

Read a history of the discovery and study of DNA and its structure. Links to a graphic, other references, and classroom activities.

Learn about the Austrian biochemist and author, Erwin Chargaff, best known for "Chargaff's Rules" which lead to the discovery of DNA's double helix structure.