The heart

• It's a muscle in your chest made of four Chambers which are called ...

  Right/left atrium (top)

  Right/left ventricle (bottom)
• The right side pumps blood to the lungs, while the left side pumps it around the body
• Arteries branch out into smaller vessels called capillaries where oxygen and nutrients diffuse into cells and waste products diffuse back into the bloodstream.
• Blood is pumped from the heart into arteries that carry it away from the heart.
• Veins carry deoxygenated blood from the tissues back to the heart
• Blood is pumped through arteries by contraction of the heart muscles
• Capillaries allow exchange between tissues and blood.