Features an introduction to blood types, blood typing and blood transfusions, with a fun interactive game to test your understanding. From the Nobel Prize Foundation.
The Franklin Institute: The Human Heart
Explores the development and structure of the human heart, follows the blood flow through the cirulatory system and teaches about heart health, with activity ideas and image gallery.
Nova Online: Cut To The Heart
Provides information on the history of heart surgery as well as details of what causes heart failure, animated diagrams and photographs of diseased hearts.