Circulatory System
The circulatory (cardiovascular) system transports blood to and from the heart with the help of blood vessels.
The heart is the center of the circulatory system and pumps blood across the entire body via arteries and veins:
- Arteries transport blood away from the heart toward other body parts. Arteries usually carry oxygen-rich blood. The smallest arteries, called arterioles, branch off larger arteries in order to supply body tissue with blood.
- Veins return the blood back to the heart. They usually carry deoxygenated blood. They branch into smaller venules to pick up oxygen-poor blood from the body tissue.
Learn the anatomy and physiology of the circulatory system (cardiovascular system) with the interactive animations below, and test your knowledge with labeling worksheets.
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The Location, Size, and Shape of the Heart
Review the location of the heart as well as it’s size and shape in this interactive tutorial and test your knowledge in the quiz.
Major system arteries of the body
Review the major systemic arteries of the body including those of the neck, arm, forearm, abdomen, pelvis, thigh, and leg in this interactive tutorial.
The four chambers of the heart and their functions
Review the four chambers of the heart as well as other features in this interactive tutorial and test yourself in the quiz.
Phases of the Cardiac Cycle
Review how the atrioventricular and semilunar valves open and close in a full cardiac cycle in this interactive tutorial.
Coronary Arteries
The cardiac arteries run along the surface of the heart, carrying oxygenated blood to the heart muscle. Review the cardiac veins and test your knowledge.
Major Blood Vessels of the Heart
The major blood vessels of the heart consist of large arteries and veins that transport blood to and from the different circulatory systems of the body.
Heart Valve Movement
The four heart valves open and close in response to pressure changes that occur in the ventricles. Review the movement of the valves in this tutorial.
Main veins of the body
Review the major systemic veins of the body including the veins of the neck, arm, forearm, abdomen, pelvis, thigh, and leg in this interactive tutorial.
How Blood Type is Determined
The blood type test is used to determine which antigenic molecules are present on RBCs. Review the procedures of the test in this interactive tutorial.
Red blood cells (erythrocytes)
RBCs are small, disc-shaped cells that circulate in the blood stream. Review the general structure and function of an RBC in this interactive tutorial.