<Li> Large collecting vessels, such as the subclavian vein, the jugular vein, the renal vein and the iliac vein . </Li> <Li> Venae cavae (the two largest veins, carry blood into the heart). </Li> <P> They are roughly grouped as arterial and venous, determined by whether the blood in it is flowing away from (arterial) or toward (venous) the heart . The term "arterial blood" is nevertheless used to indicate blood high in oxygen, although the pulmonary artery carries "venous blood" and blood flowing in the pulmonary vein is rich in oxygen . This is because they are carrying the blood to and from the lungs, respectively, to be oxygenated . </P> <P> Blood vessels do not actively engage in the transport of blood (they have no appreciable peristalsis), but arteries--and veins to a degree--can regulate their inner diameter by contraction of the muscular layer . This changes the blood flow to downstream organs, and is determined by the autonomic nervous system . Vasodilation and vasoconstriction are also used antagonistically as methods of thermoregulation . </P>

Name the type of blood vessels which carry blood from organs to the heart