Final answer:
Blood vessels branch to form a systemic circuit, which allows for targeted blood flow regulation to individual tissues, responding to changes in activity or resource needs.
Step-by-step explanation:
Blood vessels in the body branch extensively to form a systemic circuit and supply blood to many organs of the body. This arrangement permits each tissue to regulate its own blood flow independent of the other tissues. The cardiovascular system is adept at redirecting blood flow according to the needs of different tissues. When activities change, such as during exercise or after eating, the cardiovascular system allocates resources accordingly, ensuring that active tissues receive more blood.
This dynamic regulation is enabled by the branching of major arteries into minor arteries and arterioles, reaching deeply into muscles and organs, and is accomplished largely by varying vessel diameters. At the cellular level, this extensive network culminates in capillaries that facilitate the exchange of oxygen and waste products.