Let's get straight to the heart of the matter—the heart's job is to move blood. Day and night, the muscles of your heart contract and relax to pump blood throughout your body. When blood returns ...

As your heart expands, blood flows from your body into its chambers ... This short film is from the BBC series, Inside the Human Body. The 3D footage brings the topic to life and would enhance ...

Originally appeared on the NOVA Web site Cut to the Heart. Let's get straight to the heart of the matter—the heart's job is to move blood. Day and night, the muscles of your heart contract and ...