PATHOLOGY

Detailed explanation-1: -Arteries transport blood away from the heart and branch into smaller vessels, forming arterioles. Arterioles distribute blood to capillary beds, the sites of exchange with the body tissues. Capillaries lead back to small vessels known as venules that flow into the larger veins and eventually back to the heart.

Detailed explanation-2: -Arterioles are the smallest of the arteries; blood flows directly from the arterioles into capillary beds.

Detailed explanation-3: -Blood flow is slowest in the capillaries, which allows time for exchange of gases and nutrients. Resistance is a force that opposes the flow of a fluid. In blood vessels, most of the resistance is due to vessel diameter. As vessel diameter decreases, the resistance increases and blood flow decreases.