How is the circulatory system similar to a road-and-highway system?
The dendritic (branch) structure, common in nature (tree trunk to branch to twig to leaf vein; drain to rivulet to stream to river), is an efficient system for nourishing small areas while maintaining a general circulation. In any distribution system the dendritic model serves well : from such distribution systems as Fedex, UPS and the Postal Service to online retailers such as Amazon. In the human body, two of these dendritic structures work together: the arteries for feeding all the parts with blood, and the veins for removal of waste, carbon dioxide, etc. Large arteries that run down the entire body the branch out into smaller arteries, that in turn bring the blood to capillaries in each organ and limb; the reverse, from the small capillaries in the lungs to the large veins, bring the blood back to the heart to be redistributed. Similarly, multi-lane superhighways bring traffic to exits onto U.S. routes, which then bring traffic to small state highways, often only two lanes, the to county and township road, city streets, and eventually to the “capillary” of the system – your driveway.
The system of arteries and veins that carry the blood from the heart and then recirculate it. The highway system of the Circulatory System consists off a lot of one way streets.This is very similar to roads of a city. The arteries are the highways and the veins are the side streets and back roads.
Hope this helped,