Cardiac physiology is to collect de-oxygenated blood, in the right atrium, from the body via the superior vena cava, inferior vena cava and from the coronary sinus and pump it, through the tricuspid valve, via the right ventricle, through the semilunar pulmonary valve and into the pulmonary artery in the pulmonary circulation where carbon dioxide can be exchanged for oxygen in the lungs. This happens through the passive process of diffusion. In the "left heart" oxygenated blood is returned to the left atrium via the pulmonary vein. It is then pumped into the left ventricle through the bicuspid valve and into the
Portal vein Portal vein The portal vein or hepatic portal vein is a blood vessel that carries blood from the gastrointestinal tract, gallbladder, pancreas and spleen to the liver. This blood contains nutrients and toxins extracted from digested contents. Approximately 75% of total liver blood flow is through the portal vein, with the remainder coming from the hepatic artery proper. The blood leaves the liver to the heart in the hepatic veins. The portal vein is not a true vein, because it conducts blood to capillary beds in the liver and not directly to the heart. It is a major component of