Morphometry of the Arterial Tree and Venous System

Detailed measurements of the number and size of blood vessels in the living body are very difficult to perform, so reliable information is scarce. Moreover, data collected on vessels in one tissue or organ are not applicable to another. Thus one should be cautious in using morphometric data only the data for large vessels are reliable. 

The aorta is tapered, but most other arteries can be considered to have a constant diameter between branches. The rate of taper varies from individual to individual, presumably, between species. However, in the dog, the change of aortic cross sectional area can be described by the exponential equation  

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