Aðalhveinar

Aðalhveinar, also known as main veins, are a crucial component of the circulatory system in humans and other vertebrates. They are large blood vessels that carry deoxygenated blood from the body back to the heart, where it is pumped to the lungs for oxygenation. The primary main veins in the human body include the superior vena cava, inferior vena cava, pulmonary veins, and the hepatic veins.

The superior vena cava is the largest vein in the body, carrying deoxygenated blood from the upper half of the body, including the head, neck, and arms, to the right atrium of the heart. The inferior vena cava carries blood from the lower half of the body, including the legs and pelvis, to the right atrium. The pulmonary veins carry oxygenated blood from the lungs to the left atrium of the heart. The hepatic veins carry deoxygenated blood from the liver to the inferior vena cava.

Main veins play a vital role in the circulatory system by facilitating the return of blood to the heart. They are supported by a network of smaller veins and are lined with endothelial cells that help regulate blood flow and prevent blood clots. The structure and function of main veins are essential for maintaining proper blood circulation and overall health.