Watch this narrated animation which explains a breakthrough procedure using the protein p53 to fight cancer. [1:01]

See how far the dengue fever virus has spread throughout the Americas since the 1960s. [0:24]

Learn how a standard lab technique, polymerase chain reaction, amplifies a single or several copies of a piece of DNA. [0:55]

Learn about the geometrical structure of three different viruses, and how these structures affect the function of each virus. [3:22]

This video focuses on what causes the extinction of the dinosaurs. Learn about Luis Alvarez's research that led to the discovery that an asteroid caused the mass extinction. Video includes embedded quizzes that check from students' understanding of the concepts explored in the video. [33:43]

This animation features the anole lizards as an example of how a single species can split and multiply into many different species with distinct traits. [2:38]

This interactive module explores the environmental factors and species involved in five major mass extinctions.