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Your body is an amazing machine! Trillions of unique cells work together to form the tissues, organs, and body systems that allow you to run and jump, laugh and cry, feel pain and joy. Some of the body’s most complex workings hum along without you even realizing all the action that goes on behind the scenes.

For example, when you eat, the body’s digestive system breaks down food to release essential nutrients to fuel the body. The heart and cardiovascular system pump nutrients via blood to every part of the body through a network of blood vessels. At the same time, the body’s immune system stands guard, ready to jump into action to protect the body from disease and infection.