Why does ventricular pressure fall to a much lower level than aortic pressure??
Pressure in the arteries is due to the thick muscular walls that have a pulse. When the heart beats, the arteries push the blood using the muscles in the walls. This creates arterial pressure. In blood circulation, the arteries push the blood away from the heart, towards the cells of the body and the lungs. Veins, on the other hand, have much less muscle in the walls. Veins return the blood from the cells of the body, back to the heart. In the veins, there is no pulse. Blood flows in the correct direction due to valves along the way that insure blood flows back to the heart. Also, body movements keep blood flowing in the veins. The pressure in the veins is much lower than in the arteries.