THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -The venule is very thin-walled and easily prone to rupture with excessive volume. Blood flows from venules into larger veins. Just like the arterial system, three layers make up the vein walls. But unlike the arteries, the venous pressure is low.

Detailed explanation-2: -For example, blood flow is slow at the capillaries because of the high total cross-sectional area, which allows for proper nutrient exchange. Blood flow is pressure gradient over resistance or the difference between mean arterial pressure and right atrial pressure over peripheral vascular resistance.

Detailed explanation-3: -But unlike the arteries, the venous pressure is low. Veins are thin-walled and are less elastic. This feature permits the veins to hold a very high percentage of the blood in circulation. The venous system can accommodate a large volume of blood at relatively low pressures, a feature termed high capacitance.

Detailed explanation-4: -Your main pulmonary artery and your aorta are the two great vessels that carry blood out of your heart. A crucial difference is that your pulmonary artery carries oxygen-poor (deoxygenated) blood, while your aorta carries oxygen-rich (oxygenated) blood.