part of part of has part has part composed primarily of subdivision of skeletal system thoracic rib cage postcranial axial skeletal system rib skeletal system rib series TAO:0002100 UBERON:0014478 rib skeleton FMA:265719 set of all ribs Subdivision of skeletal system that consists of all ribs and rib joints in an organism. In many vertebrates this consists of the combination of the rib cage and all rib joints, but some vertebrates have ribs outside the thoracic rib cage. rib endochondral element