human_reference_atlas has part connected to blood vessel endothelial cell Homo sapiens anterior vena cava azygos vein https://upload.wikimedia.org/wikipedia/commons/b/b4/Azygos_vein.png vena azygos MESH:D001401 UMLS:C0004526 galen:AzygosVein azygos vein GAID:528 uberon UBERON:0001594 EMAPA:18250 azygos venous tree An unpaired vein which in humans arises from the right ascending lumbar vein or the vena cava, enters the thorax through the aortic orifice in the diaphragm, and terminates in the superior vena cava; unlike humans, mice have a single and left-sided azygos vein that develops from the paired embryonic cardinal venous system and drains most of the right and left thoracic walls into the left anterior vena cava[MP]. check development relationships in different species MA:0002085 azygos vein Wikipedia:Azygos_vein AS FMA:4838 NCIT:C53029 vein