Explain how the difference in the …

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Ventricles usually have very thick walls so that they can withstand the pressure with which they have to pump blood so that blood circulates through each and every tissue of the body. But, left ventricle is the one that actually sends the blood to most body tissues, so the LV is the thickest due to which aorta has to withstand higher pressure. But, RV does not need that much pressure or thickness as it has to pump blood only to the lungs. So, the pulmonary artery also experiences relatively lower pressure than aorta. So, considering (1), thicker the ventricular wall, more would be the pressure it's associated artery has to withstand. Considering (2), more the number of tissues to which blood must reach and more the distance the blood must travel to reach tissues, greater will be the pressure on the great arteries. (GREAT ARTERIES IS THE COLLECTIVE TERM FOR AORTA AND PULMONARY ARTERY)