part of part of connects connects organ part lobe of thyroid gland isthmus of thyroid gland http://upload.wikimedia.org/wikipedia/commons/9/9e/Gray1174.png neuronames:2643 Wikipedia:Thyroid_isthmus UBERON:0001609 EHDAA2:0002031 EMAPA:18195 thyroid gland isthmus A narrow median bridge that joins together the lower thirds of the two lateral (right and left) lobes of the thyroid gland and usually covers the second and the third tracheal rings; the thyroid isthmus is variable in presence and size, can change shape and size, and can encompass a cranially extending pyramid lobe (lobus pyramidalis or processus pyramidalis), remnant of the thyroglossal duct. In mammals and in some reptiles, the thyroid is composed of two lobes connected by an isthmus; in birds and amphibians, the thyroid consists of two isolated lobes. (...) Despite these morphological differences, the ontogeny of the thyroid follows the same pattern in all vertebrates (...).[well established][VHOG] thyroid isthmus MA:0000727 isthmus glandulae thyroideae isthmus isthmus glandulae thyroideae UMLS:C0229583 EHDAA:5777 NCIT:C32887 FMA:49178 VHOG:0000739 SCTID:245539003 thyroid gland midbrain-hindbrain boundary