Page 65 - Miracles in Our Bodies

The most perfectly structured pump in the world is now
beating on the left side of your chest. With its marvellous de-

sign and unceasing contractions, your heart makes the entire

blood in your body complete 1,000 full cycles in a day.
The heart is a pump made of flesh, which is approximately

as big as one's fist. Nevertheless, it is clearly the strongest, the

most durable and the most efficient engine in the world with re-

spect to its capacity. We have many reasons to express the

strength of the heart in this way. Most important, the heart
uses a great deal of energy when it beats. With the energy used

by the heart, blood can be raised up to 3 metres high. It may be

helpful to give an example in order to make it easier to compre-
hend the heart's capacity. In an hour the heart can produce an

amount of energy that is enough to lift an average car

approximately one metre above the ground.

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