A Journey Inside Your Heart

An average car has a suitcase-sized engine weighing around 300 pounds. A jet engine is a couple tons heavy, and several people could fit inside. But the most powerful engine out there is the size of your fist and weighs no more than a can of soup. It’ s the human heart… How does it work?

The human heart is essentially a big muscle that’s constantly at work. It beats 100,000 times a day, close to 40 million times a year, and over 2 billion in a lifetime! With each of those beats, 1/3 of a cup of blood moves through the heart. In a day, that’s up to 2,000 gallons! Any other engine would break down under… .

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