The “macrovasculature” refers to the larger structures that make up the circulatory system of the body, specifically the arteries and the veins. Even though both carry blood, arteries and veins have different characteristics and functions.
Arteries are designed to carry blood away from the heart. Arteries are muscular and very elastic. This is because they are designed to absorb the pressure generated by the squeezing heart. The blood that is carried inside arteries is under pressure, which helps the blood get delivered to the far corners of the body. Most arteries in the body carry oxygen-rich blood, which is bright red. The only exception to this rule is the pulmonary artery, which carries blood with low oxygen concentration away from the heart and into the lungs.
Veins collect blood from all the tissues in the body and bring it towards the heart. The blood inside the veins is deoxygenated (poor in oxygen), which is a darker tone of red. The only exception to this is the pulmonary veins, which bring oxygenated blood back towards the heart from the lungs. The content inside the veins is not under pressure. Blood returns to the heart by the combination of one-way valves inside the veins and the squeezing of the body’s large muscles.« Back to Glossary Index