A description of the purpose and function of a human heart including an explanation of double circulation and why heart attacks occur. Includes a demonstration of ECGs and their use in measuring heart rate and function. The risk of a heart attack can be lowered by not smoking, reducing the amount of fatty foods eaten and taking regular exercise.

First broadcast:
2 March 2007

Use this clip to introduce or recap the basic structure of the heart and explain its role in respiration. Students could draw a diagram, or create a 2D model of the blood's circulation through the heart.