University of Utah
University of Utah: Cardiovascular Pathology Index
This site features a detailed index of photographs for cardiovascular pathology. You can see what a normal human heart looks like and what a sick one looks like too. Come and check it out.
BBC
Bbc: Ks2 Bitesize: Science: Circulation
Background information review of key concepts about the circulatory system, including the heart and pulse. Tis site provides diagrams, activities, and quiz questions.
Other
World Invisible: The Human Circulatory System: Blood Circulation
A labeled diagram of the major veins and arteries in the human body.
Other
Digital Frog: Frog Circulation
A digital diagram from Digital Frog of the circulatory system of a frog. Very nice, and very fake since it is not a real frog.
BBC
Bbc: Gcse Bitesize: Cardiovascular System
A great overview of the Cardiovascular System, its structure and functions. See diagrams of the heart, and learn how the blood flows through the heart.