The aorta - excellently constructed
The aorta is a much more complex "tube" than scientists once thought. At first glance, the aortic arch may look like the curved handle of an umbrella. But this description is not quite correct. In fact, the aortic arch is not just two-dimensionally curved, but has a three-dimensional curvature that is more like a semicircular piece of a spring. On a flat surface, one end of the semicircle would point upwards.
Why is it constructed in this way? This causes the blood not to simply flow through the aortic arch like water in a river bend, but to swirl the blood in two spirals. On the inner side of a river bend, the water flows more slowly, which allows sediments to settle. On the outside of the bend, however, the water flows faster and can even erode the river bank. In the aorta, dangerous sediments could be formed due to different flow velocities of the blood on the inner side of the bend. However, since the blood in the aorta is swirled in a spiral shape and thus its inner wall is flushed more evenly, this danger is less.
The aorta is really excellently constructed. With good reason, the Bible book of Psalms says, "I [am] made wonderful in a fearsome way" (Psalm 139:14).
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