part_of part of part of has potential to develop into contributes to morphology of artery pharyngeal arch respiratory system artery head blood vessel pharyngeal arch artery http://upload.wikimedia.org/wikipedia/commons/8/84/Gray473.png add specific artery derivatives The third, fourth, and sixth arches, along with the seventh intersegmental arteries and the left dorsal aorta, are the primary contributors to the normal aortic arch and its major thoracic branches Do not confuse with arch of aorta. Number varies - Lampreys have 8, hagfishes 15; only up to 6 appear in embryonic development in most gnathostome fishes and all tetrapods presumptive structure pharyngeal vasculature structure with developmental contribution from neural crest