Heart beats 2,5bn times
The circulatory system that is made up of arteries, veins and capillaries is about 96500km long.
Our heart beats more than 2,5billion times in an average lifetime.
The heart muscle contracts without stimulus from the nervous system, unlike other muscles. Signals for the heart to beat come from the sinoatrial node near the top of the right atrium.
About 1percent of our blood is made up of white blood cells and the number of cells can double in a day when our bodies respond to infection. - Innerbody.com; medterms.com