T he heart is the body's hardest-working muscle. Whether you're awake or asleep, or exercising or resting, your heart is ...

The circulatory system consists of one heart, five liters of blood, and approximately 96,000 kilometers of blood vessels, responsible for transporting nutrients and waste throughout the body.

Learn about the circulatory system with these interactive learning resources for KS2 Science students aged 7-11 from BBC Bitesize.